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T H E O F C A N A D I A N J O U R N A L MEDICAL SONOGRAPHY Volume 2, Issue 3 • Fall 2011 • Renal Doppler Ultrasound Protocol • Family Trip Can Lead to the ED • Inexpensive Easy-to-Make Scrotal Phantom • Morel-Lavallee Lesion www.csdms.com Publications Agreement Number 40025049 • ISSN: 1923-0931 Canada Diagnostic Centres Calgary Edmonton Some of Canada’s Most Qualified Talent CONSIDERING A REWARDING CAREER? Canada Diagnostic Centres (CDC) attracts Canada’s most qualified, thanks to our focus on providing our team with a wealth of professional opportunities and access to leading edge technology. We’re able to keep these valuable team members with a supportive environment that encourages a work/life balance. We work closely with all our employees to maximize their career satisfaction with us. Talented sonographers who join our team enjoy very competitive employment compensation and benefits. CDC is a proud Clinical Partner of the Diagnostic Medical Sonographer programs at the Southern Alberta Institute of Technology (SAIT) and at the Northern Alberta Institute of Technology (NAIT). We are committed to excellence in healthcare education. WHY CDC? As a sonographer with CDC, your specialty training will help us deliver expert diagnostic imaging services to our patients, including obstetrical (4D), abdominal, pelvic, small parts, venous and arterial Doppler examinations. We utilize the latest in ultrasound and RIS/PACS system, as well as ergonomically designed examination rooms. CDC OFFERS YOU: • Competitive wages • Superior employee health and disability benefits • Weekday hours, no on-call requirements, no shift work • Leading-edge technology • Employee and family assistance program • Attractive and supportive work environment • Employer matching RRSP program • Signing bonus • Corporate wellness and ergonomics programs • Moving allowance • Flexible work hours • On-site 4D training • Commitment to excellence in diagnostic imaging services • Support for ongoing education and skills-based training SONOGRAPHERS Start an Exceptional Career With Us Today Discover the benefits of a career with CDC, and join our team of leading experts. Contact Tracy Kujat at: 403-212-5851 or [email protected] Human Resource Manager Exceptional Patient Care CanadaDiagnostics.ca e t al . CSDMS News | Nouvelles deDelanisSCEM Message from the President Message du président W elcome to the fall 2011 edition of The Canadian Journal of Medical Sonography! I hope that everyone had a wonderful summer and had a chance to relax and reload. One of the biggest improvements that I can appreciate as a CSDMS member over the past 14 years or so has been the introduction of our own journal. Kathleen Foran and Kim Boles, along with all the fine members of the new editorial board, have worked extremely hard to make CJMS a great success. Another major factor in helping the journal run so smoothly is the great guidance and knowledge that we receive from Andrew John Publishing Inc. (AJPI). John Birkby (president and publisher) and Susan Harrison (managing editor) have been fantastic to work with and truly have the best interests of our society on their mind. AJPI is a “nuts and bolts” organization that is willing to assist in any way possible to make CJMS successful. I want to encourage sonographers to submit articles and not to fret over grammar, context, etc. Susan will work out any bumps in a completely professional manner. There are a few avenues that CJMS is working toward/ investigating at this time: peer review, article collaboration (possibly with Australia and America), and having articles included that can be used for continuing professional education (CPE) credits. This growth will take time but is something that is on the horizon. We had our Annual General Meeting and Education Conference in Kelowna, British Columbia, this past May. I want to thank the planning committee in Kelowna for putting together a great program! The conference attendance was great, and for the first time we offered a live webcast for our members who could not attend. This was very successful, and we plan to implement this option for future conferences. We also recorded some lectures that we will make accessible at a later date on our CSDMS website in the members-only section. This is another step in giving our members increased opportunities for CPE credits. Finally, I would like to personally thank Kim Boles, not only for all that he has done for CSDMS over the past couple of years, but also for his contributions to CARDUP and the sonography profession over many years (I won’t say how many) and the mentorship that he has provided to me in my new role. I know that Kim will continue to make his mark on our profession as the editor-in-chief of CJMS and as a sonographer who has a plethora of knowledge in every single aspect of Canadian health care. Thanks Kim. Tom Ball, MEd, BSc, CRGS, CRCS V oici donc l’édition automnale de La Revue canadienne d’échographie médicale (RCEM) qui nous réunit à nouveau. J’espère que l’été a été agréable et reposant. Cette revue qui est la nôtre représente à mes yeux de membre des 14 dernières années l’une des grandes avancées qui marquent l’évolution de la Société canadienne des échographistes médicaux (SCEM). Le succès que connaît la RCEM, nous le devons certes à Kathleen Foran, à Kim Boles et à tous les membres de la nouvelle équipe de rédaction qui veillent avec détermination à la réussite de la publication. Sur ce sujet de la réussite de notre revue, on ne saurait passer sous silence les précieux conseils et le savoir d’Andrew John Publishing Inc. dont nous bénéficions. John Birkby, président et éditeur, et Susan Harrison, directrice de l’édition, accomplissent un travail remarquable, toujours au mieux des intérêts de la Société. Maison d’édition pour qui les rouages de la publication n’ont plus de secrets, Andrew John Publishing est prêt à tout mettre en œuvre pour assurer le rayonnement de la RCEM. Que les échographistes n’hésitent pas à proposer des articles même s’ils ont l’impression que leur grammaire ou leur orthographe n’est pas au point, Susan les aidera à aplanir les difficultés d’une main de maître. La RCEM étudie des possibilités en ce moment, notamment l’examen par des pairs, la publication d’articles en collaboration avec d’autres revues (Australie et Amérique peutêtre) et la publication d’articles ouvrant droit à des unités de formation dans l’optique du perfectionnement professionnel continu. Cette expansion nécessite bien sûr une préparation, mais déjà elle pointe à l’horizon. Pour ce qui est de l’assemblée générale annuelle et de la conférence à Kelowna (Colombie-Britannique) en mai dernier, je remercie et je félicite le comité de planification local qui nous a réservé une programmation hors pair! Les participants ont été nombreux et, pour la première fois, nous avons pu offrir un webinaire en direct aux absents, une diffusion très courue d’ailleurs, au point que nous songeons à répéter l’expérience à l’avenir. Nous avons également enregistré des exposés qui paraîtront sous peu sur le site Web dans la section réservée aux membres. Nous multiplions ainsi les possibilités pour les membres d’obtenir des unités de formation dans le cadre du perfectionnement professionnel continu. Enfin, je tiens à remercier personnellement Kim Boles, non seulement de son dévouement à la tête de la SCEM dans les deux dernières années, mais également de sa contribution exceptionnelle auprès de l’Association canadienne des professionnels autorisés en échographie diagnostique et à la profession durant toutes ces années (je ne dirai pas combien), et du mentorat qu’il m’a bien volontiers offert avant mon entrée en fonction. Pour bien longtemps encore, Kim brillera au sein de la profession, que ce soit comme rédacteur en chef de la RCEM ou comme échographiste qui connaît le système de santé canadien comme le fond de sa poche. Merci Kim. Tom Ball, MEd, BSc, CRGS, CRCS www.csdms.com The Canadian Journal of Medical Sonography | Fall 2011 3 RADIOLOGY CARDIOLOGY GYNECOLOGY ERGONOMIC ERGONOMIC STRETCHERS FOR F OR DIAGNOSTIC D IAG N OS TI C U ULTRASOUND LT RAS OU N D ECHO-FLEXTM 4800-DC-20 NEW N EW BUTTONS B UT TON S CONTROLLER CONTROLLER NEW N E W SOFT SOFT POLYURETHANE P O LYUR ET TH HANE SSTIRRUPS TIIR R T RU UP U PS NEW N EW GY GY CUTOUT C U TO TOUT SPECIALITY CHAIRS AND OFFICE SEATING ECHO-FLEXTM 4800-GY-26 MODEL 200 Tel.: T el.: 450 678-5468 FFax: ax: 450 445-9837 [email protected] www.ibiom.com www .ibiom.com Canadian Society of Diagnostic Medical Sonographers Société canadienne des échographistes médicaux Contents Volume 2, Issue 3 • 2011 Volume 2, Issue 3 • 2011 Publications Agreement Number 40025049 EDITOR-IN-CHIEF Kim Boles CSDMS News 3 Message from the President • Message du président Tom Ball, MEd, BSc, CRGS, CRCS ASSOCIATE EDITOR-IN-CHIEF Kathleen Foran EDITORIAL BOARD Lianne Broughton, Francine Caron, Nanette Denis, Dal Disler, Cathy Fix, Stuart Gibbs, Carol Gillis, Chris Harrington, Wendy Lawson, Verna Maschio, Vern Parkinson MANAGING EDITOR Susan Harrison ART DIRECTOR 7 Meet the Editorial Board Original Articles 10 Renal Doppler Ultrasound Protocol with Comparative Abnormal Case Study Lori Arndt, CRGS, CVRS, RDMS, RVT Andrea Brierley PROOFREADER Scott Bryant TRANSLATOR 18 A Long Car Trip with Your Family Can Lead You to the Emergency Department: A Case Report Wilson Miranda, BSc, RDCS, Shin-yee Chen, MD Marie Dumont ADVERTISING John Birkby (905) 628-4309 [email protected] CIRCULATION COORDINATOR Brenda Robinson [email protected] ACCOUNTING Susan McClung GROUP PUBLISHER John D. Birkby _______________________________________ 22 An Inexpensive Easy-to-Make Scrotal Phantom Leonardo Faundez, MA-Ed, BSc, CRGS, CRVS, RDMS, RVT 28 Morel-Lavallee Lesion: A Case Report Megan MacNevin Announcement 33 Maintaining the Schedule of Unit Values for the Medical Imaging Workload Measurement System Arlene L. Thiessen, RN, for the Canadian Institute for Health Information For Instructions to Authors, please visit www.andrewjohnpublishing.com/ CJMS/cjmsinstauthors.html _______________________________________ Return undeliverable Canadian Addresses to: 115 King St W., Suite 220, Dundas, ON L9H 1V1 Canadian Journal of Medical Sonography, is published three times a year by Andrew John Publishing Inc., with offices located at 115 King Street West,Suite 220,Dundas, ON L9H 1V1. ••••• We welcome editorial submissions but cannot assume responsibility or commitment for unsolicited material.Any editorial material, including photographs that are accepted from an unsolicited contributor, will become the property of Andrew John Publishing Inc. The publisher and the Canadian Society of Diagnostic Medical Sonographers shall not be liable for any of the views expressed by the authors published in Canadian Journal of Medical Sonography, nor shall these opinions necessarily reflect those of the publisher. www.csdms.com Cover images (left to right): Forest river in the fall - Algonquin Provincial Park, Wild Bull Moose - Spray Valley Provincial Park in Kananaskis Country Alberta, Bow Valley Parkway - Banff National Park, Alberta Above images (left to right): Waterfalls in Sheep River Valley - Alberta, Elk Island National Park - Edmonton, Forest Trail - Quebec The Canadian Journal of Medical Sonography | Fall 2011 5 Located in the beautiful city of Edmonton, Alberta, we are seeking: Diagnostic Medical Sonographers Insight Medical Imaging has been providing Edmonton and surrounding areas with medical imaging services for over 50 years. We offer competitive wages, employee benefits and pension, continuing education assistance, an attractive vacation package and a relocation allowance. We provide education, resources and programs such as: In-house training, consulting and assessments; work life balance; massage therapy; and employee and family assistance programs. Flexible Work Schedules/Time Away from Work: Depending on business needs, employees may participate in one of several work options: Flexible start and end times and job sharing. We encourage personal time off with an initial annual vacation leave of three weeks, which increases based on years of service. Other leaves with pay include time off for personal emergencies and learning activities. If you are a self directed, highly motivated individual who would enjoy practicing in a supportive team environment, we would welcome the opportunity to review your qualifications and valued skills. Successful applicants must be currently registered or be eligible for registration with ARDMS and/or CARDUP Please forward your resume to: Lori Neufeld, Director Human Resources Cell: (780)278-6027, Fax: 1(780)638-6530; email: [email protected] CSDMS News Meet the Editorial Board A s of the current issue, the Canadian Journal of Medical Sonography has a new editor-in-chief, Kim Boles, an associate editor-in-chief, Kathleen Foran, and a full slate of editorial board members committed to advancing the journal and making it an essential publication for Canadian sonographers. We invite you to read on and meet this dedicated group of individuals. Kim Boles, CRGS, CRVS, RDMS, RVT Editor-in-Chief Many of you will know me from my previous roles as CSDMS president and CARDUP chairperson. I am currently affiliated with the Ottawa Hospital, in Ottawa, Ontario, as the charge sonographer in the Vascular Diagnostic Center, Division of Vascular Surgery, Department of Surgery. This new role as editor-in-chief of the CJMS will be a challenging one. Since the inauguration of the journal in January 2010, the CSDMS Board of Directors and the executive director, Kathleen Foran, have shared the editorial responsibilities. With the newly appointed editorial board, the emphasis will be on encouraging more Canadian sonographers to make quality submissions to the journal. Kathleen will be an integral member of the editorial board and as the CSDMS executive director will oversee the financial aspects of the CJMS and fulfill a joint leadership role, as associate editor-in-chief, to ensure continuity with CSDMS policies and focus. With help from the editorial board and Susan Harrison at Andrew John Publishing, I hope to make the journal one you will continue to enjoy and to which you will make a submission for publication. Kathleen Foran, BSc, CRGS, CRCS, CRVS, RDMS, RDCS, RVT Associate Editor-in-Chief I have been working as a sonographer since 1988, and I am registered in the fields of cardiac, vascular, abdomen, OB/GYN, neurological, and breast sonography. During my career, I have acted as a clinical instructor, lead sonographer, educational program coordinator, adjunct professor, and consultant. My current activities are dedicated to the role of executive director for CSDMS and CARDUP. I am excited to see the journal come to fruition and to participate on the CJMS Editorial Board. Lianne Broughton, CRGS, CRCS, CRVS, RDMS, RDCS, RVT On the editorial board, I will be assisting in the generalist and vascular specialties. I am currently the vascular director for CSDMS. I am currently the senior ultrasound technologist and technical director of the Non-invasive Vascular Laboratory at the Hamilton General Hospital, in Hamilton, Ontario. Most of my career has been spent in the Hamilton area, but I have also worked in Bermuda over the years. www.csdms.com The Canadian Journal of Medical Sonography | Fall 2011 7 Me e t the Editorial Board Francine Caron, CRGS, CRVS, RDMS, RVT, TIM Bonjour à tous. My specialty on the board of the CJMS is vascular. I work in a community hospital of 405 beds in St-Jérome, Québec. We have a team of three surgeons and four vascular sonographers. I have been working as a sonographer since 1984, and am registered in the fields of abdomen, OB/GYN, neurosonology, and vascular, but my current activities are dedicated to the vascular field. I have many sonographer friends all across Canada. It is a pleasure for me to be part of this journal, and I hope to serve you well. Nanette Denis, CRGS, RDMS For the CJMS, my specialty is generalist. I am currently the ultrasound coordinator for the Fetal Assessment Unit at the Royal University Hospital in Saskatoon, Saskatchewan. I have been an active participant in many societies and committees over the years, most recently completing two terms as the western director for CSDMS and accepting a third term as the CSDMS liaison on the SOGC Diagnostic Imaging Committee. I am a member of the Saskatchewan Licensure Committee as well as the Committee for the Responsible Use of Ultrasound and have spent many years as a preceptor for the SAIT ultrasound students as well an instructor for the Department of Obstetrics and Gynaecology Resident Training Program. I have extensive experience in obstetrical ultrasonography and fetal echocardiography. Dal Disler, CRGS, CRCS, RDMS, RDCS My specialty on the editorial board is cardiac. Currently, I am the supervisor of the Echocardiography Laboratory at the Alberta Children’s Hospital, in Calgary, Alberta. Previously, I was the supervisor of the Foothills Hospital Echocardiography Laboratory, developed the echocardiography curriculum and taught as an instructor for the SAIT Polytechnic ultrasound program, and was the education coordinator of echocardiography for the Calgary Health Region. I am a past board member and chair of CARDUP. Over the years, I have published several articles in cardiology related to echocardiography. My interests are varied and include echocardiography, technology, golf, and fishing. Cathy Fix, CRGS, CRCS, RDMS, RDCS For CJMS, my specialty is generalist. I have been actively involved in the ultrasound community for over 25 years; my current position is the ultrasound supervisor for St. Paul’s Hospital, in Vancouver, British Columbia. I became a clinical instructor with the UBC Department of Radiology in 2003. During my career as a sonographer, I have had the opportunity to work as a clinical application specialist in general and cardiac ultrasonography and also in ultrasound sales. My background also includes working at BCIT for a short time as a clinical instructor. I have lectured nationally and internationally and have co-authored and authored several papers. My specialties include radiology, vascular sonography, and women’s health. I have a strong commitment to image quality and expanding the knowledge of fellow sonographers. In my spare time, I like holidays in the sun, enjoy time on a recently purchased float home, and paint. Stuart Gibbs, BSc, CRGS, CRCS, CRVS, RDMS, RDCS, RVT My specialties for CJMS are generalist, cardiac, and vascular. Throughout my career, I have been actively involved in several professional associations: past president of the BC Ultrasound Society, and western director and secretary of CSDMS. Presently, I am at the Abbotsford Regional Hospital and Cancer Centre in British Columbia as the supervisor of general sonography, cardiac sonography, and the Vascular Laboratory. It is an honour to be asked to be on the editorial board of the CJMS. 8 The Canadian Journal of Medical Sonography | Fall 2011 www.csdms.com Meet the Editorial Board Carol Gillis, BHSc, MA Ed, CRGS, CRCS, CRVS, RDMS, RDCS, RVT My specialties for CJMS are generalist, cardiac, and vascular. I have extensive experience as both an ultrasound professional and educator, and am currently a faculty member with the School of Health Sciences at Dalhousie University, in Halifax, Nova Scotia. Throughout my career, I have been actively involved in several professional associations: past director (2003– 2007) for CSDMS; past president of the Nova Scotia Society of Diagnostic Medical Sonographers; and a member of both CARDUP and the American Registry of Diagnostic Medical Sonographers. I have been privileged to work with the Canadian Medical Association as an accreditation surveyor/chair for diagnostic medical ultrasound programs since 1999. Chris Harrington, CRGS, CRCS, CRVS, RDMS, RDCS, RVT My specialty area is generalist. I am the program coordinator for the Ultrasound Training Program at the Health Sciences Centre, in Winnipeg, Manitoba, a position I have held for almost 20 years now. I teach ultrasound physics and abdominal and vascular sonography (and some MSK). I continue to be excited by this ever-changing field, and have a particular interest in how best to teach this specialty to both ultrasound students and residents. Wendy Lawson, BSc, Dipl HS, CRGS, CRVS, RDMS, RVT I bring knowledge and experience to the CJMS editorial board in my specialty areas of musculoskeletal, obstetrical, and breast sonography. In addition to my role as a clinical sonographer, I am a professor for the collaborative Mohawk-McMaster Medical Radiation Sciences Program, in Hamilton, Ontario. My first love is teaching, mentoring a new generation of sonographers and sharing my passion for the profession. I am active in the ultrasound professional community; sitting on the CSDMS Board of Directors and co-chairing the CSDMS/CARDUP National Education Council. I am pleased to be able to contribute to the CJMS and look forward to facilitating the sharing of best practices and experiences within our very dynamic profession. Verna Maschio, BTech (Applied Health Science), CRGS, CRCS, CRVS, RDMS, RDCS, RVT My area of specialty for CJMS is vascular. Presently, I am employed as a vascular instructor in the Diagnostic Medical Sonography Program at the Northern Alberta Institute of Technology (NAIT), in Edmonton, Alberta, and as a casual sonographer at the Sturgeon Community Hospital, in St. Albert, Alberta. I have many years of clinical experience in general, cardiac, interventional, neonatal, and high-risk obstetrical fields, attained while employed in both the private and public sectors. I currently sit as one of the vascular representatives on the CARDUP Board of Directors and have been actively involved with the Alberta Diagnostic Sonographers Association (ADSA) in the past. I have presented lectures at CSDMS, ADSA, allied health care professional conferences, and provincial radiology conferences. Vern Parkinson, CRGS, CRCS My area of specialty for the journal is cardiac. I look forward to helping to advance the spread of knowledge in our profession; ultrasound training has come a long way since my days at the University of Alberta Hospital, in Edmonton, Alberta, when “real-time” ultrasonography was in its fairly early days and “static b-scanning” was an indispensible part of obstetrical, abdominal, and superficial structure ultrasonography! I am involved with CSDMS in various capacities, including a term on the board and chair, co-chair, and worker-bee on three Conference Planning Committees. With CARDUP, I am currently enjoying a second term on the board of directors (as cardiac director). Last year, I sat on the Cardiac Examination Item Writing Committee, which was both an honour and a huge learning opportunity. Presently, I am the supervisor of echocardiography for the Vancouver Island Health Authority, in Victoria, British Columbia. www.csdms.com The Canadian Journal of Medical Sonography | Fall 2011 9 Original Article Renal Doppler Ultrasound Protocol with Comparative Abnormal Case Study Lori Arndt, CRGS, CVRS, RDMS, RVT About the Author Lori Arndt works for Radiology Consultants Associated, Mayfair Vascular Centre, in Calgary, Alberta. Correspondence may be directed to [email protected]. T he detailed renal Doppler ultrasound examination has a somewhat-controversial role in many ultrasound departments. Not only is the examination time lengthy, but obtaining information that is consistently reliable and diagnostic in providing an impression of the vascular status of the kidney, and what that means for the management of the patient, is often in question. Duplex scanning is limited to 95% sensitivity and 90% specificity for detecting renal artery stenosis when compared with digital subtraction angiography (DSA).1 But since the contrast used in DSA is nephrotoxic, the use of DSA presents a risk of worsening renal function if it is already compromised.1 Other imaging tests such as CT angiography (CTA) and MR angiography (MRA) may be preferred, especially if the duplex scan is technically inadequate. However, ultrasound studies, besides being non-invasive, add a physiological component to complement these imaging modalities when endeavouring to determine the hemodynamic significance and severity of renovascular disease, if present. This article describes a protocol used in the examination of a particular case. An incidental finding of a coarctation was elicited during the renal Doppler study on this patient. The characteristics of normal and abnormal waveforms of the aorta, main renal arteries, and parenchymal arteries are reviewed here. The two methods for detecting renal artery stenosis described in this essay are the direct and indirect methods. The direct method refers to the interrogation of the main renal arteries. The indirect method involves the assessment of the parenchymal arteries within the kidney itself and the distal renal artery at the hilum.2–4 Of course, the presence of accessory renal arteries may not be noted as they are difficult to image due to their small calibre and inconsistent site of 10 The Canadian Journal of Medical Sonography | Fall 2011 origin; but with increasingly superior equipment resolution, these small arteries are being recognized more frequently. Indication, Preparation, History, and Technique The main clinical indication for ordering renal Doppler ultrasonography is hypertension, often with an inability to medically control the high blood pressure. An acute rise in blood pressure to above high normal limits, labile blood pressure, or hypertension in a young patient (20–40 years) are reason to investigate the kidney vessels to rule out stenosis, obstruction, or pathology that may compromise the flow to and within the kidney.1 Renal failure develops if the amount of functioning renal tissue is reduced by greater than 80%.1 Renal artery stenosis is usually caused by atherosclerosis and less frequently by fibromuscular dysplasia.1 The patient should be well hydrated by drinking three to four glasses of water 1–2 hours prior to the examination and should ideally fast 6–8 hours before the test.3 Abdominal gas can never be obliterated, even with a prolonged fast, so varied positioning of the patient to avail oneself to the ideal scanning windows is essential.5 Obtaining a pertinent medical history is important, specifically regarding cardiovascular risk factors such as smoking, diabetes, and cholesterol levels. The acuity of onset, duration, and treatment of the patient’s high blood pressure are important to know. A brachial blood pressure should be taken before the examination if not known by the patient or indicated on the requisition. Some laboratories routinely auscultate the abdomen to listen for bruits that may be present in the abdominal midsection. It is helpful to www.csdms.com A r ndt have knowledge of abnormal creatinine levels that would indicate the possibility of decreasing renal function. Obesity in a patient often presents a difficulty, but scanning from the flank minimizes the distance to the kidney.4 When imaging midline vasculature (the aorta and main renal arteries), constant compression applied to the abdomen may aid in moving obscuring gas.4 Lowering the bed and standing for midline scanning allows pressure to be applied from the sonographer’s body and shoulder rather than the elbow and wrist, reducing repetitive strain. As this examination can take up to 1 hour, attention to ergonomics must be in the mind of the sonographer throughout. Turning the patient in a decubitus position for a flank approach eliminates scanning through the small bowel and colon. A variable that is not controllable involves how well the patient follows your instructions for the various breathing manoeuvres needed in order to assess the vessels as accurately as possible.4 Renal Doppler Protocol The renal Doppler protocol includes a morphological assessment of the kidney to include length, an evaluation of cortical thickness, and documentation of pathology. Sagittal measurements of each kidney should be obtained. The aorta should be assessed followed by duplex Doppler evaluation of the main renal arteries and the parenchymal vessels. Aortic Assessment A curvilinear probe with a frequency of 3.5–5 MHz is preferred for imaging the aorta as well as the kidneys.6 With the patient in a supine position, obtain sagittal and transverse images of the aorta to document the calibre of the aorta as well as the presence of atherosclerosis or aneurysm. Colour Doppler images complement the black and white images by enhancing the presence of atherosclerotic disease or hypoechoic thrombus. Optimize the colour scale and colour gain to ensure proper colour fill in.6 Obtain a spectral signal in the aorta at the level of the superior mesenteric artery (SMA), which is in close proximity to the origin of the renal arteries. The peak systolic velocity (PSV) at this level is used to calculate the renal-aortic ratio (RAR). The usual velocity of the aorta ranges from 80 to 100 cm/s, with a moderate-resistance waveform. The kidney is a highly vascular organ, receiving approximately 20% of the cardiac output.5 Therefore, the vascular supply to the kidneys is reflected in a moderateresistance waveform, indicating forward flow throughout diastole. The upstroke of the aorta waveform should be straight with a sharp peak, which indicates no significant disease upstream from that site (Figure 1). Distal to the renal www.csdms.com Figure 1. Aorta – normal waveform. arteries, the aortic waveform takes on a triphasic pattern reflecting the high-resistance flow into the lower extremities. Figure 1 shows the appropriate level at which the PSV of the aorta should be obtained. The RAR is the ratio of the highest PSV of each renal artery divided by the PSV of the aorta at the level of the SMA.1,6 An RAR of ≥3.5 is considered abnormal, indicating the presence of a stenosis causing a >60% diameter reduction in the renal artery.1,6 Renal Arteries: Direct Assessment In a transverse plane, the main renal arteries are observed arising from the aorta about 1 cm inferior to the origin of the SMA.5,6 In transverse, the right renal artery arises from the aorta just inferior to the left renal vein at about a 10 o’clock position.3,6 The usual course of the right renal artery is found posterior to the inferior vena cava (IVC) as it travels to the hilum. The left renal artery lies behind the left renal vein at about the 5 o’clock position.3,6 It continues in a posterior direction toward the left renal hilum. The renal veins course parallel to the arteries.5 Figures 2 and 3 illustrate the renal vessel anatomy. Colour Doppler ultrasonography is helpful in identifying the renal arteries and for observing whether there is any significant aliasing that might indicate a stenosis. Generally, renal artery stenosis due to plaque formation occurs at the origin and proximal portion, whereas stenosis due to fibromuscular dysplasia (FMD) occurs in the mid- to distal portion of the artery.1,6 Doppler samples should be taken from the origin to the distal segment of the renal artery. An angle correction of 60° should be maintained.5,6 The velocity of the main renal arteries normally ranges from 50 to 150 cm/s, with anything higher than 180 cm/s considered abnormal1,5,6 and indicating renal artery stenosis. The PSV normally decreases as the arteries are followed The Canadian Journal of Medical Sonography | Fall 2011 11 Re nal Doppler Ultrasound Protocol V A R L Figure 2. Diagram of the transverse renal vessels. Figure 3. Transverse renal vessels. Figure 4. Origin of the right renal artery. Figure 5. Mid-right renal artery. Figure 6. Distal right renal artery. Figure 7. Mid-left main renal artery. Figure 8. Diagram of the coronal flank approach through the kidney to the renal artery. 12 The Canadian Journal of Medical Sonography | Fall 2011 Figure 9. Hilar region sample (coronal). www.csdms.com A r ndt Figure 10. Interlobar arteries (arrows). Figure 12. Interlobar artery. distally and into the kidney. The renal arteries have a lowresistance signal, with the resistive index (RI) normally <0.7 and increasing slightly with advancing age. Figures 4–6 demonstrate the correct placement of the sample volume and an angle correction of 60° along the length of the right renal artery. The RI equation is (1 − EDV/PSV) × 100, where EDV indicates end diastole velocity. The equation is calculated by the machine with cursors placed at peak systole and end diastole.1,6 The experienced sonographer should be able to assess the waveforms qualitatively, but obtaining an RI is an essential part of the complete examination. The left renal artery has a steeper lie, creating some difficulty in maintaining a 60° angle correction (Figure 7) from an anterior approach. If an angle other than 60° is used to remain parallel to the flow stream, this must be documented for reference in follow-up studies. Renal Arteries (Distal): Indirect Assessment A flank approach to interrogate the distal (hilar portion) renal arteries and the intrarenal vessels may prove to be the easiest method in patients in whom it is difficult to accurately assess the arteries from the anterior abdominal window (Figures 8 and 9). With the patient in a lateral decubitus position and scanning from the flank in line with the coronal plane of the kidney, the distal (hilar) region of www.csdms.com Figure 11. Interlobar artery. the renal artery is easily visualized. Waveforms change distal to a significant stenosis; therefore, Doppler evaluation of the hilar portion of the main renal artery indirectly shows the effects of a >60% narrowing. The hemodynamic effect downstream to a critical stenosis demonstrates a delayed acceleration time as well as a tardus-parvus waveform in stenoses >80%.3 Because the position of the transducer is directly in line with the artery, a 0° angle of insonation is used, along with a large sample volume of 3–5 mm. These technical parameters allow for quick and easy sampling of the artery as it enters the hilum of the kidney. The sweep speed should be increased to 100 mm/s or “fast,” depending on the “knobology” of the specific equipment.3 This allows for better detail of the waveform components so that the acceleration time can be measured more accurately and the early systolic peak (ESP), when present, easily identified.3 The acceleration time (flow onset to peak systole interval) should be ≤100 ms in a normal renal artery.3 Often, the sonographer’s subjective observation is used to conclude whether the upstroke to peak systole is delayed. The remainder of the indirect assessment is composed of at least one sample of the parenchymal arteries (segmental or interlobar) at the superior and inferior poles and midkidney. The interlobar arteries are easy to locate as they course between the medullary pyramids and their somewhat-vertical position allows for a 0° insonation along the vessel (Figure 10). The interlobar or segmental arteries in the sinus of the kidney reflect changes in the waveform when a significant (>60%) stenosis is upstream from the sample site. Spectral samples from normal interlobar arteries are shown in Figures 11 and 12. Note that the sweep speed is increased, which extends each pulsed waveform allowing for detailed waveform characterization.3 Figures 13 and 14 clearly illustrate the ESP. This compliance peak, which appears as a pre-systolic notching, is a specific marker that indicates an absence of a proximal significant stenosis in the main renal artery. It may take some finetuning to visualize the ESP while sampling through the parenchymal arteries. As part of the protocol a sagittal measurement of each kidney should be recorded and a note made of the cortical The Canadian Journal of Medical Sonography | Fall 2011 13 Re nal Doppler Ultrasound Protocol Figure 13. Early systolic peak. Figure 14. Early systolic peak. Figure 15. Normal right kidney with measurement. Figure 16. Mid-left renal vein. Figure 17. Proximal left renal vein. Figure 18. Sagittal proximal aorta (abnormal). thickness (Figure 15). As well, the right and left renal veins should be interrogated to prove patency. Respiratory phasicity is usually seen in the renal vein waveform, as demonstrated in Figures 16 and 17.6 Each kidney measured 9 cm in length and demonstrated normal morphology. The aorta was unremarkable in its structure. The patient’s body habitus allowed for excellent visualization of the vasculature of the abdomen and kidneys. The aorta, main renal arteries and veins, and parenchymal arteries were interrogated. A survey with colour Doppler showed generally good perfusion to the cortical edge of each kidney. The PSV of the aorta was 134 cm/s but did not appear to have a normal moderate-resistance pattern (Figure 18). Case Report A 20-year-old female was referred for renal artery Doppler study due to the finding during a routine physical of hypertension. Her physician had also heard an abdominal bruit. She was a generally well person with no other pertinent medical history. 14 The Canadian Journal of Medical Sonography | Fall 2011 www.csdms.com A r ndt Figure 19. Transverse right renal artery. Figure 20. Transverse left main renal artery. Figure 21. Superior interlobar artery. Figure 22. Mid-interlobar artery. Figure 23. Distal aorta (abnormal). Figure 24. Superior mesenteric artery (abnormal). Qualitative observation suggested that the increased diastolic flow velocities throughout diastole were atypical for a normal proximal aorta waveform. The main renal arteries were widely patent, with the spectral tracing revealing a tardus-parvus waveform bilaterally with a PSV of 63 cm/s in the right renal artery and 86 cm/s in the left renal artery. The waveforms demonstrated the characteristic appearance of a tardus-parvus waveform, with a significantly increased acceleration time, broad peak with a gradual downslope, and dampened velocities. The RIs were 0.45 and 0.49, respectively (Figures 19 and 20). The parenchymal interlobar arteries displayed similarly abnormal waveforms throughout both the right and left kidneys (Figures 21 and 22). The differential strongly suggested a central pathology such as coarctation of the aorta or an aortic stenosis. If this were the case, then all peripheral arteries distal to the coarctation should reflect the same change in their waveforms. It was decided, therefore, to sample the distal aorta, SMA, and both common iliac arteries. Normally the distal aorta and peripheral arteries take on a high-resistance, triphasic flow pattern, reflecting the distal high-resistance vascular bed of www.csdms.com The Canadian Journal of Medical Sonography | Fall 2011 15 Re nal Doppler Ultrasound Protocol Figure 25. Right common iliac artery (abnormal). Figure 26. Left common iliac artery (abnormal). Figure 27. Normal common iliac artery waveform. Figure 28. Normal distal aorta waveform. Figure 29. Coarctation of thoracic aorta. the lower extremities.5,6 The result of our interrogation found a low-resistance pattern in major arteries distal to the renal arteries (Figures 23 and 24). Figures 25 and 26 show the abnormal low resistance of the common iliac arteries. As well, the PSVs in the common iliac arteries of 52 cm/s and 35 cm/s are well below expected velocities, especially in a patient of this age. For comparison, Figures 27 and 28 illustrate the normal triphasic pattern seen in the aorta and common iliac arteries. The radiologist report recommended further assessment, and an urgent MRA was ordered by the patient’s physician 16 The Canadian Journal of Medical Sonography | Fall 2011 to rule out coarctation and aortic stenosis of the aorta. The MRA confirmed a diagnosis of coarctation (Figure 29). Coarctation is a narrowed segment of the aorta, generally occurring in the thoracic aorta (proximal descending portion), just beyond the left subclavian artery origin (Figures 29 and 30). It can also occur, more rarely, in the abdominal aorta. The generally accepted standard treatment is open surgery with resection of the narrowed portion with an end-to-end interposition graft insertion, with sutured anastomosis to the aorta (Figure 31). Of interest, there is a trend toward an endovascular approach to repairing a coarctation. This procedure involves dilating the area of interest with a large-diameter angioplasty balloon inside a covered tubular stent graft. The intent is to create a controlled rupture of the aorta at the coarctation site only, with the covered endograft containing the rupture itself. This method is best applied when only a slight widening of the coarctation is needed as the risk in more severe cases is an uncontrolled rupture of the aorta. In either case, a coarctation should be repaired as the strain on the heart to pump blood against the narrowed orifice of the coarctation can cause long-term cardiac damage (hypertrophic cardiomyopathy). Conclusion This essay presents a basic protocol to assess the vasculature www.csdms.com A r ndt Figure 30. Coarctation of aorta. Figure 31. End-to-end graft repair. to the kidneys and within the parenchyma of the kidneys. The differentiation between normal and abnormal waveform patterns is clearly demonstrated. Whether a sonographer chooses to use direct or indirect Doppler assessment for a dedicated study of the vasculature of the kidneys, the information obtained can be helpful in determining if further imaging studies are needed. It is my intent to encourage sonographers, when faced with the question of renal artery stenosis in a general department, to try to obtain spectral tracings from parenchymal arteries, using the criteria outlined for indirect assessment. Even though this essay shows comparative results from a coarctation that is an uncommon pathology to be diagnosed in this manner, it should be understood that a significant arterial narrowing (>60%), whether in the aorta or main renal arteries, shows the same changes to the parenchymal vessels of the kidney. The hemodynamics of downstream effects of arterial stenosis can be applied to the duplex interrogation of any artery in the body; therefore, whether disease is present or not in the sampled vessels, the understanding of waveform characteristics is of critical importance. 4. 5. 6. Coombs P. Color duplex of the renal arteries: diagnostic criteria and anatomical windows for visualization. JVU 2004;28(2):89–97. Dubbins PA, McAteer M, ed. Clinical Doppler Ultrasound, 2nd edition. Philadelphia: Churchill Livingstone (Elsevier) Publishers; 2006. Zweibel WJ, Pellerito JS, Ross A, ed. Introduction to Vascular Ultrasonography, 5th edition. Philadelphia: Elsevier Saunders; 2005. References 1. 2. 3. Myers K, Clough A. Renovascular diseases. In Koster J, ed. Making Sense of Vascular Ultrasound – A Handson Guide, 1st edition. London: Arnold Publishers; 2004. Isaacson JA, Zierler RE, Spittell PC, Strandness DE. Noninvasive screening for renal artery stenosis: comparison of renal artery and renal hilar duplex scanning. J Vasc Tech 1995;19(3):105–10. Isaacson JA, Neumyer MM. Direct and indirect renal arterial duplex and Doppler color flow evaluations. J Vasc Tech 1995;19(5–6):309–16. www.csdms.com The Canadian Journal of Medical Sonography | Fall 2011 17 Original Article A Long Car Trip with Your Family Can Lead You to the Emergency Department: A Case Report Wilson Miranda, BSc, RDCS, Shin-yee Chen, MD About the Authors Wilson Miranda (left) and Shin-yee Chen are both members of the Ottawa Heart Institute, in Ottawa, Ontario. Correspondence may be directed to [email protected]. T he case presented here illustrates the usefulness of echocardiography in the assessment of patients with pulmonary embolism. In addition to providing information regarding right ventricular function and pulmonary pressure, it caught an impending paradoxical embolism (IPDE) in the act as it traversed through a patent foramen ovale. Recognition of this unusual entity and the appreciation of its clinical implications by the sonographer led to the activation of the appropriate treatment pathway, which may have saved the patient from catastrophic complications. Case Report A 67-year-old woman presented to the emergency department with a 3-day history of generalized weakness, dizziness, mild dyspnea, and chest pain. The chest pain was described as a persistent retrosternal pressure, which became worse with exertion. There was no pleuritic component. In retrospect, she had been feeling unwell since her 10-hour car trip, approximately 1 week prior to presentation. She had initially experienced bilateral lower extremity weakness and pain. The pain had since resolved, but the weakness remained. Due to symptoms of urinary incontinence and dysuria, she was seen at a local clinic 3 days prior to presentation and was started on azithromycin. On the evening of her presentation, she felt so weak and dizzy that she could not get up. The emergency health service was activated and the patient was brought to the emergency department. Due to a language barrier, the patient could provide only limited information regarding her past medical history. She indicated that she had received medical treatment for a thyroid problem, but had otherwise been in good health and 18 The Canadian Journal of Medical Sonography | Fall 2011 was not on any regular medication. Physical examination revealed a blood pressure of 123/82 mm Hg, a heart rate of 100 bpm, a respiratory rate of 25 breaths/min, an oxygen saturation of 96% on room air, and a temperature of 36.3°C. Results of an examination of the head, neck, and abdomen were within normal limits. There was no lower extremity erythema, warmth, or swelling. Cardiac examination revealed normal heart sounds with no systolic or diastolic murmur. The jugular venous pressure could not be determined with certainty. A respiratory examination revealed normal breath sounds bilaterally with no wheezes or crackles. The patient was reviewed by the medicine service and was started on dalteparin sodium (Fragmin) for a suspected pulmonary embolism. Computed tomography (CT) of the chest confirmed a large saddle embolus with extensive pulmonary embolic disease involving all lobar and multiple peripheral arteries (Figure 1). Also present were right chamber dilatation, interventricular septal straightening, and reflux of contrast into the inferior vena cava suggestive of elevated pulmonary pressure. CT of the head was performed to rule out any intracranial pathology contributing to the patient’s condition. This revealed no evidence of an acute infarction or bleeding. The patient remained hemodynamically stable in the emergency department overnight. An echocardiogram was requested the next day to assess right ventricular function. This revealed a mild dilatation of the right ventricle with moderately reduced systolic function. The left ventricle was small with normal systolic function. There was moderate tricuspid regurgitation and mild pulmonary hypertension. The systolic pulmonary pressure was estimated to be 44 mm Hg. A large sausage-like www.csdms.com Miranda and Che n A A B B C C Figure 1. A–C, Computed tomography of the chest revealing a large saddle embolus (arrows) with extensive pulmonary embolic disease. www.csdms.com Figure 2. A–C, An impending paradoxical embolism caught in the act as it traversed through a patent foramen ovale; images obtained in the modified apical four-chamber and subcostal views. The Canadian Journal of Medical Sonography | Fall 2011 19 Family Trip Can Lead to the ED mass was identified in the right atrium, traversing through a patent foramen ovale into the left atrium. The appearance was diagnostic of an IPDE (Figure 2). Cardiac surgery consultation was initiated, and the patient was taken to the operating room to undergo pulmonary embolectomy. By the time she arrived in the operating room, she was in full-blown cardiogenic shock with severe right ventricular heart failure. Upon anesthesia induction, she went into cardiac arrest and required an emergency sternotomy and open cardiac massage. She was stabilized, and a large clot was evacuated from her atria upon cannulation. The residual atrial septal defect was closed. A thrombectomy of the main pulmonary artery and thromboendarterectomies of the left and right pulmonary arteries and the segmental arteries were performed. Despite concerns regarding a significant residual clot burden in the subsegmental level, she survived the surgery with enough right ventricular function to carry her through. She was started on heparin after the surgery. Ultrasonography of the lower extremity was performed the next day but revealed no evidence of any residual deep vein thrombosis. Her recovery was slow, with complications of atrial fibrillation, shock liver, renal insufficiency, and superficial sternal wound infection. She was discharged from hospital approximately 1 month after her surgery. Discussion Deep vein thrombosis in the lower extremity may dislodge and migrate through the inferior vena cava and the right cardiac chambers to reach the pulmonary arterial circulation, resulting in pulmonary embolism. With the Valsalva manoeuvre, or in the setting of significantly elevated right heart pressure due to massive pulmonary embolism, the migrating thrombus may pass from the right atrium into the left atrium through a patent foramen ovale, which is estimated to be present in up to 35% of the normal population.1 This phenomenon, known as paradoxical systemic embolization, may lead to catastrophic consequences, such as stroke or myocardial infarction. In this case, a large thrombus became entrapped in the foramen ovale as it migrated from the right to the left atrium, enabling the sonographer to capture the echocardiographic image of the IPDE. IPDE is associated with high mortality, with most deaths occurring within 24 hours of diagnosis.2 While the optimal treatment for this condition remains controversial, early diagnosis is of the utmost importance in clinical decision making. In a systematic review, for this rare condition, transthoracic echocardiography was diagnostic in 39.6% of reported cases, whereas transesophageal echocardiography was required in 56.9%. CT and magnetic resonance imaging 20 The Canadian Journal of Medical Sonography | Fall 2011 were used in 2.9 and 0.6% of patients, respectively.3 In this case, the diagnosis was made with transthoracic echocardiography within minutes of initiating the study. The study was performed portably at the bedside, without the inconvenience, invasiveness, medication or contrast administration, radiation exposure, or patient discomfort associated with other diagnostic modalities. However, it behooves the sonographer to recognize this rare entity and perform a thorough search for any intracardiac mass or thrombus, with particular attention to the interatrial septum. This is especially difficult since the reasons cited for the diagnostic test referral may be wide and varied. The majority of patients may present with symptoms consistent with pulmonary embolism, including dyspnea, chest pain, syncope, shock, and signs of right ventricular failure. About half of these patients may have manifestations of systemic emboli, such as cerebral vascular accidents, peripheral vascular ischemia, myocardial infarction, or visceral ischemia.4 The diagnosis of IPDE may be made by echocardiography via direct visualization of the thrombus entrapped in the patent foramen ovale. The thrombus is usually a mobile mass of irregular shape, serpentine or lobulated, with changing configuration throughout the cardiac cycle. Sometimes only the right or the left atrial aspect of the IPDE is seen, making it difficult to differentiate from atrial mxyoma. Other differential diagnoses, such as congenital structures, infectious vegetations, or sessile right atrial thrombi, must also be excluded.5 At the same time, echocardiography can be used to assess for findings associated with concurrent pulmonary embolism, such as right ventricular dysfunction, McConnell’s sign, and elevated pulmonary pressure. It is also useful for ruling out any significant dysfunction of the left ventricle and cardiac valves in unstable patients. In this case, despite earlier assessment with CT of the chest, which did detect right cardiac chamber dilatation and evidence of pulmonary hypertension, the diagnosis of IPDE was not made until the assessment with echocardiography. Treatment options for IPDE include anticoagulation, thrombolysis, and surgical thromboembolectomy. As the majority of deaths are due to cardiogenic shock or right heart failure, it has been postulated that hemodynamic compromise secondary to massive pulmonary embolism is the main underlying mechanism. As such, thrombolysis has been proposed as the treatment of choice. However, this is associated with systemic embolization in 23.5% of patients. While a recent systemic review failed to establish improved survival with either thrombolysis or surgical thromboembolectomy over anticoagulation alone, surgical thromboembolectomy showed a nonsignificant trend www.csdms.com Miranda and Che n toward improved survival and reduced systemic embolism and composite of mortality and systemic embolism.3 Thrombolysis showed a non-significant trend toward the opposite.3 Treatment should be considered on a case-by-case basis and individualized according to the patient’s clinical profile and local expertise. Fortunately for the patient in this case, pulmonary thromboendarterectomy was available at our institution and the risk of systemic embolization was minimized as much as possible. Had the diagnosis of IPDE not been made by echocardiography, the patient would likely have received thrombolysis for pulmonary embolism given her progressive hemodynamic instability and may have been left with a significant neurological deficit if she survived the event. This case highlights the importance of a full echocardiographic examination in patients with suspected pulmonary or systemic embolism. References 1. 2. 3. 4. 5. Meacham R, Headley A, Bronze M, et al. Impending paradoxical embolism. Arch Intern Med 1998;158:438–8. Aboyans V, Lacroix P, Ostyn E, et al. Diagnosis and management of entrapped embolus through a patent foramen ovale. Eur J Cardiothorac Surg 1998;14:624–8. Myers PO, Bounameaux H, Panos A, et al. Impending paradoxical embolism: systemic review of prognostic factors and treatment. Chest 2010;137:164–70. Meacham RR III, Headley AS, Bronze MS, et al. Impending paradoxical embolism. Arch Intern Med 1998;158:438–48. Huwer H, Winning J, Isringhaus H, et al. Transit thrombus entrapped in a patent foramen ovale. Heart Lung 2004;33:191–3. E ExpectMore tM Make a difference in the lives of others ers and in your own. Join Northern Health! Heallth! Northern Health leads the way in promoting moting health and providing health services es for Northern and rural populations. Our vision of building a strong primaryy health care system for all Northerners will create a dynamic work environment that challenges all of your skills. W e are als so dedicated to optimizing the expertise of our staff and relationships with regional nal educational institutions We also for training opportunities such as new w physicians, physicians nurses, and paramedical professionals. fessionals. W e invite you to join our team as we build b healthier communities and develop a network of outstanding healthcare pro ofessionals. We professionals. Exciting Opportunities fo for or . . . Ultrasound/Sonographer Ultr asound/Sonographer - V Various arious Locations throughout Northern Health h As an Ultrasound/Sonographer you perform p diagnostic medical sonographic duties as a regularly scheduled service for the Hospital and surrounding area. Y ou also perform related maintenance mainttenance and clerical functions. You 7 REHVXFFHVVIXOLQWKLVSRVLWLRQ\RX R ZLOOKDYHREWDLQHGUHFRJQL]HGWUDLQLQJ DVDQXOWUDVRXQGRUUDGLRORJ\WHFKQRORJ J\SURJUDPDQGFHUWLÀFDWLRQE\WKH 7REHVXFFHVVIXOLQWKLVSRVLWLRQ\RXZLOOKDYHREWDLQHGUHFRJQL]HGWUDLQLQJDVDQXOWUDVRXQGRUUDGLRORJ\WHFKQRORJ\SURJUDPDQGFHUWLÀFDWLRQE\WKH American R egistry of Diagnostic Med ical Sonographers and have knowledge of ultrasound procedures and equipmen nt. Registry Medical equipment. 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RUNZLWKLQVXSSRUWLYHHQYLURQP PHQWV : :RUNZLWKLQVXSSRUWLYHHQYLURQPHQWV LOOVWKDW\RXZHUHWUDLQHG GIRU 8VHVN 8VHVNLOOVWKDW\RXZHUHWUDLQHGIRU XLQJ(GXFDWLRQ &RQWLQ &RQWLQXLQJ(GXFDWLRQ X XLWLRQUHLPEXUVHPHQWRI SHU\ HDUWRVXSSRUWRQJRLQJHGXFDWLRQ 7 7XLWLRQUHLPEXUVHPHQWRISHU\HDUWRVXSSRUWRQJRLQJHGXFDWLRQ LIXOVXUURXQGLQJVLQFUHGL EOHV FHQHU\\ ZLOGOLIHKDELWDWFDPSLQJ KLNLQJ VZLPPLQJVNLLQJ %HDXW %HDXWLIXOVXUURXQGLQJVLQFUHGLEOHVFHQHU\ZLOGOLIHKDELWDWFDPSLQJKLNLQJVZLPPLQJVNLLQJ the northern way of caring 7 RÀQGRXWKRZ\RXFDQ R ExpectMore eDQGWRDSSO\RQOLQHFKHFNRXWRXUZH HEVLWHDW www w.northernhealth.ca/careers eers 7RÀQGRXWKRZ\RXFDQExpectMoreDQGWRDSSO\RQOLQHFKHFNRXWRXUZHEVLWHDWwww.northernhealth.ca/careers www.csdms.com The Canadian Journal of Medical Sonography | Fall 2011 21 Original Article An Inexpensive Easy-to-Make Scrotal Phantom Leonardo Faundez, MA-Ed, BSc, CRGS, CRVS, RDMS, RVT About the Author Leonardo Faundez is an ultrasound professor at the Michener Institute for Applied Health Sciences in Toronto, Ontario. Correspondence may be directed to [email protected]. U ltrasound phantoms have become useful tools in training sonography students. Phantoms offer advantages such as allowing sonographic concepts to be more easily demonstrated1 and facilitating the scanning of organs and structures without the need of a living patient.2 Despite the extensive list of commercially available phantoms (see, e.g., 3-Dmed at http://www.3-dmed.com/ Phantoms_For_Ultrasound_&_X-ray_Ultrasound_Diagnostic_Training_Models.html; 3rd Rock Ultrasound at http://www.emergencyultrasound.com/products.php?cat=1; Blue Phantom at http://www.bluephantom.com/category.aspx? cid=539; and CIRS at http://www.cirsinc.com/main_us.html), there is currently only one scrotal phantom on the market (from Blue Phantom), and its price is quite significant when considering current budgetary limitations. Nevertheless, it is possible to create an inexpensive scrotal phantom that will enrich student learning. Scrotal imaging is challenging for novice sonographers due to its uniqueness in terms of anatomy, curved scanning surface, and relatively mobile targets (testes). Prior to the use of the homemade scrotal phantoms, students in the Ultrasound Program at the Michener Institute for Applied Health Sciences, in Toronto, Ontario, were exposed to scrotal imaging on only a theoretical basis. They learned the scrotal cross-sectional anatomy, normal sonographic anatomy, and pathological findings. Having only theoretical background before the clinical component definitely meant that our students were at a disadvantage. In addition, scrotal sonography carries a significant level of uneasiness, especially for female sonographers. At our institution, the number of female sonography students is greater than that of male students, and having to wait until their clinical rotations to scan scrota caused their uneasiness to escalate. Taking all of this into account, there was a need at our 22 The Canadian Journal of Medical Sonography | Fall 2011 institution to better prepare our students via simulation of scrotal imaging. To bridge this gap, I created an inexpensive and relatively easy-to-make scrotal phantom. Scrotal Phantom Three scrotal phantoms were created, with a total cost of materials of approximately C$8.00. To make this inexpensive and relatively easy-to-make scrotal phantom, the following steps were performed: 1. 2. Hollow oval-shaped structures were used to simulate the testes (Figure 1). The original purpose of these hollow structures was to be a toy for a birthday loot bag. Each of these came with a small touch-activated light inside that was removed by a small cut made with scissors so that it would have a hollow centre. Using a syringe without a needle, various substances were injected into the hollow space to see which produced the best sonographic tissue equivalency. After several trials, it was decided that the best substance was the hand cream used in our laboratory (Surgipath Aloeponic, Surgipath Medical Industries). Krazy Glue was used as a sealer to close the cut in the structure to prevent any spilling. To simulate the epididymides, two items were used. One was a worm-shaped item, also a birthday loot bag toy (Figure 2). Only two of these worm-shaped items were found when purchasing the materials. For the remaining simulated epididymides, a jelly substance was used (Figure 3). This latter item had to be cut into an epididymis-like shape (Figure 4). These simulated epididymides were glued with Krazy Glue to the outer surface of the oval-shaped structures (Figure 5). This www.csdms.com Faunde z Figure 1. Hollow oval-shaped structures used for simulated testes (Sticky Light). Figure 2. Worm-shaped item used to simulate epididymides (All New Sticky Toy). Figure 3. Jelly substance used to simulate epididymides (item on sale without package; unable to determine product name). Figure 4. Jelly substance cut and shaped to simulate epididymides. Figure 5. Simulated epididymis stuck to simulated testis. Figure 6. Simulated testes and epididymis. Note the unrealistic gap between these two structures. 3. resulted in an unrealistic wide gap between the simulated testis and epididymis (Figure 6). An extra-large glove was used for the scrotal sac. The fingers were tied together using an elastic band or medical tape; then the glove was flipped inside out www.csdms.com creating a sac-like structure (Figures 7 and 8). Two simulated testes with epididymides were then placed inside the sac (Figure 9) so that the fingers taped together were between the testes. In addition, the two simulated testes were placed so that the epididymides The Canadian Journal of Medical Sonography | Fall 2011 23 A n Inexpensive Easy-to-Make Scrotal Phant om Figure 7. Extra-large glove utilized as scrotal sac. The fingers were tied together using an elastic band or medical tape. Figure 8. Glove was flipped inside out creating a sac-like structure. Figure 9. Simulated testes/epididymides placed inside the sac-like structure created with a glove. Figure 10. Home-made scrotal phantom (ultrasound gel seen on its surface). Figure 11. Simulated testis in its long axis. Figure 12. Simulated testis in its short axis. 4. 24 faced laterally to re-create their natural location. The simulated testes with epididymides then needed to be embedded in a liquid. Filtered water (from a Brita filter) was found to be better than ultrasound gel and tap water: it was extremely difficult to eliminate air bubbles trapped in the ultrasound gel, which made The Canadian Journal of Medical Sonography | Fall 2011 visibility challenging; as for tap water, when left for some hours, air bubbles started to form, thus affecting visibility. Sufficient filtered water was then poured into the sac to cover the simulated testes with epididymides. An elastic band was used to secure the top to prevent spilling (Figure 10). www.csdms.com Faunde z Figures 11 and 12 show examples of sonographic images of the simulated testes. The presence of tiny echogenic foci in the simulated testes represents air bubbles trapped in the hand cream. Although presence of air is not desirable, in this case, it actually mimics tiny calcifications (microlithiasis). To store the scrotal phantoms after use, drain the filtered water, dispose of the gloves, and gently dry the simulated testes and epididymides with paper towel and place them in a dry box or container. Laboratory Exercise During a tutorial prior to the laboratory exercise, a demonstration on how to scan the scrotal phantom was given. The majority of the questions from the students were about sonographer-patient interaction (e.g., explanation given to the patient, patient set-up, etc.). For the laboratory exercise, students were asked to work in pairs, as is routinely done at our institution. The student playing the role of the patient was asked to wear a gown (on top of his or her own clothes), lie down on the stretcher, and hold the scrotal phantom from its top with one hand during the examination to prevent excessive movement. Students were asked to place the scrotal phantom at the level of their knees to simulate the male pelvis and legs. In addition, students were given an example of a scanning protocol to follow. Each student had 25 minutes to scan the phantom. Of the four laboratory sessions, two were conducted by me and two by another instructor. During these sessions, faculty assisted students by emphasizing the scanning technique in terms of using different windows, applying pressure, and obtaining the long and short axes of each testis, and the advantages and disadvantages of angling versus sliding for sweeps, etc. Furthermore, students were encouraged to imagine themselves in the real situation and anticipate any issues regarding scanning and patient interaction. Student Feedback Students were asked to provide feedback about this laboratory exercise by posting their comments on an electronic platform, BlackBoard. (Students had the option Table 1. Student Feedback Obtained after Scrotal Imaging Laboratory Sessions Using the Homemade Scrotal Phantoms Student 1: “I thought scanning the scrotal phantom was good practice today; it was more difficult than I had anticipated. I’m glad I got the opportunity to use it because I hadn’t realized getting the long or short axis would be so tricky.” Student 2: “Using the scrotal phantom was good. I didn’t realize how movable they could be. Also I didn’t expect that the long and short axes wouldn’t be in true sag [sagittal] or trx [transverse]. It was good practice to see that in the lab.” Student 3: “The scrotal phantoms were invaluable for several reasons. Their mobility, contoured surfaces, and testes orientation all contributed to excellent practice. What you used for the epididymis may be more confusing than helpful in its current form. Perhaps a later model could have a structure located where the epididymis would be found, even if sonographically it did not resemble it. That way, students could still practise locating the epididymis and using it as a landmark.” Student 4: “First assumption, I was expecting that for this lab, we would be scanning the scrotal phantom laying on its own on the stretcher. However, we actually simulated the patient as well. This was helpful as it let us practise the patient set-up and experience the proper ergonomics when doing scrotal ultrasonography. Like our transvaginal practice labs, putting us in the patient’s shoes will help us with our patient care skills.” Student 5: “I think scanning that scrotal phantom was definitely helpful in preparing for our clinical semester. I was able to sweep the scrotum as outlined in the manual. It was good practice since we have not scanned a very curved surface such as the scrotum. I think the phantoms were made well, in that we were able to get scrotal images very similar to the pictures we have been seeing in class. We were also able to experience the difficulty of scanning testis as it can be mobile within the scrotum. One area where I had difficulty was finding the epididymis. I was able to catch the head [of the epididymis], but it was not located where the epididymis is expected to be.” Student 6: “I think that being able to practise scanning the scrotal phantom was a huge benefit. After all, we have the Medsim [ultrasound simulator] as our only opportunity to experience transvaginal ultrasonography before clinical [the clinical component], and I think that an outlet to experience patient interaction, patient gowning, and realistic scanning for scrotal ultrasonography is just as important. After scanning the phantom, I feel I know more of what to expect and certainly more of how to scan (i.e., windows to use, how and when to slide versus angle etc.).” Student 7: “The scrotal phantom was great practice and provided a little bit of insight on what to expect in clinical.” Student 8: “I thought it was a great experience and nice to experience scanning a scrotum before clinical. The movement of the model was very similar to what I can imagine [occurs with] a real patient. Thanks for taking the time to develop this for us.” Student 9: “It was definitely better than nothing. I got a feel for how I’d have my hand and arm and how I’d like to try to avoid touching the patient’s inner thighs. The testicles were pretty great, realistic on screen and pretty realistic physically. The excess fluid was obviously not an example of normal anatomy, but similar to a hydrocele, so not a huge drawback. I just reread the scrotal protocol in the lab manual and realised how much we missed out on [the] epididymis. It’s a shame that part didn’t work out better as I’m still feeling uncertain about how to manage those sweeps and images.” www.csdms.com The Canadian Journal of Medical Sonography | Fall 2011 25 A n Inexpensive Easy-to-Make Scrotal Phant om to submit their feedback anonymously.) Nine of 23 students submitted feedback; eight used BlackBoard and one used email. The feedback received is included in Table 1. Discussion Overall, seven of nine students referred to the laboratory exercise as a beneficial learning experience (students 1, 2, 3, 5, 6, 7, and 8). Their reasons varied in terms of why this was a useful learning experience, from the exposure to scanning to the patient care interaction. One of the most imperative characteristics for an ultrasound phantom to be effective is that it must mimic human tissue.3 Students found the scrotal phantoms realistic in terms of their sonographic characteristics (“scrotal images very similar to the pictures we have been seeing in class,” “realistic scanning,” and “realistic on the screen” [students 5, 6, and 9]) and physical characteristics (“contoured surfaces and testes orientation,” “curved surface,” and “pretty realistic physically” [students 3, 5, and 9]). Because of this, students were able to experience some of the challenges of scanning the scrotum, including finding the long and short axes (students 1 and 2). Students realized that placing the transducer in true sagittal or true transverse plane to the body did not guarantee obtaining the long and short axes, respectively. The scrotal phantom also allowed students to experience the mobility of the testes while scanning (students 2, 3, 5, and 8). Students found it frustrating to keep losing the long and short axes of the testes when either increasing or decreasing the pressure applied with the transducer or performing the heel-toe (or reversed) manoeuvre, which is routinely done for these scans. The scrotal phantoms also allowed the students to practise the appropriate ergonomics for scrotal sonography (“experience the proper ergonomics” and “I got a feel for how I’d have my hand and arm” [students 4 and 9]). This is important for novice sonographers in terms of learning how to anchor their scanning forearm on the patient’s thigh, or realizing they are not able to rest their scanning hand as when, for example, scanning the abdomen. In fact, initially, since novice sonographers take longer to scan, they may experience more discomfort and fatigue in their scanning arms when scanning scrota as proper anchoring may not be possible. During the initial scrotal phantom tutorial, the majority of the questions were about the sonographer-patient interaction. The anxiety level was quite evident, especially in the female students. Students asked about what to do in certain situations that may arise during scanning: giving instructions to the patient, the positioning of towels under the scrotum and the gown to secure the patient’s penis against his pelvis, the refusal of a female sonographer by a patient, etc. Based on their feedback, our students were able 26 The Canadian Journal of Medical Sonography | Fall 2011 to simulate these situations during the laboratory session when using the homemade scrotal phantoms (“helpful as it let us practise the patient set-up … putting us in the patient’s shoes,” “patient interaction, patient gowning,” “how I’d like to try to avoid touching the patients inner thighs” [students 4, 6, and 9]). The scrotal phantoms provided an opportunity for students to practise all of the issues mentioned and to experience, to some degree, the uncomfortable feelings associated with performing this type of examination. The tutorial and laboratory session gave the students a starting point to mentally prepare for such clinical situations. Regarding limitations, nine of 23 students gave feedback about the homemade scrotal phantoms, which is a relatively small number. In addition, the simulated epididymides had some limitations (students 3, 5, and 9). First, there was an unnatural gap between the simulated testis and epididymis (see Figure 6). Second, the jelly substance used to make some of the simulated epididymides partially dissolved in the filtered water. As a result, students had difficulty finding them. Another limitation involved some of the hollow ovalshaped structures used for the simulated testis not having an entirely oval-shape inside. This resulted in some of the testes having “square” indentations (Figure 13). In addition, the simulated testes had no mediastinum. Since filtered water was poured in the scrotal sac created by the glove, the simulated testes were immersed in this water. This created a “pseudo-hydrocele” (see Figures 11 and 12). Furthermore, some tiny air bubbles got trapped while injecting the hand cream into the hollow structures, resulting in “pseudo-microlithiasis” or “pseudocalcifications” (see Figures 11, 12, and 14). It can be argued that these last two limitations may actually be advantages since they simulate pathologies. In fact, one student commented on this: “excess fluid was obviously not an example of normal anatomy, but similar to a hydrocele, so not a huge drawback” (student 9). There are other features worth emphasizing regarding these homemade scrotal phantoms. The simple steps to make them are highly reproducible provided the adequate materials are available. The cost of the materials for three phantoms is more than 600 times cheaper than one commercially available phantom (from Blue Phantom). Not only are the created phantoms inexpensive, they are also reusable. Moreover, storage of these scrotal phantoms is simple, and little space is required. Overall, these homemade scrotal phantoms provided students with an enriching scrotal imaging simulation. This is further supported by comments such as: “I feel I know more of what to expect and certainly more of how to scan” (student 6), and “[this exercise] provided a little bit of insight on what to expect in clinical” (student 7). These www.csdms.com Faunde z Figure 13. Simulated testis in its long axis having a “square” indentation. Figure 14. Simulated testis in its short axis with “pseudomicrolithiasis” and “pseudo-calcifications.” phantoms have since become important tools in the training of sonography students. 2003;86:3–5; http://www.rbrs.org/dbfiles/journalarticle _0089.pdf. Accessed October 15, 2010. Ophir J, Maklad NF, Jaeger PM. United States Patent. 1981; http://www.google.ca/patents?id= AR84AAAAEBAJ&printsec=description&zoom= 4#v=onepage&q&f=false. Accessed October 15, 2010. 3. Conclusion In conclusion, these inexpensive, easy-to-make, and reusable scrotal phantoms serve as a teaching tool for novice sonographers during their didactic training. Despite their limitations, the phantoms provide novice sonographers with the opportunity to experience not only some of the scanning challenges but also patient care–related challenges of scrotal imaging. As stated by De Maeseneer et al.,2 an ultrasound phantom can be adapted to meet specific needs, and this is exactly the case for these homemade scrotal phantoms. As for future steps, better items and planning are needed to create more effective and realistic simulated epididymides. Regarding future research, feedback is currently being collected from the sonography students who used these scrotal phantoms in the didactic portion and are currently completing their clinical rotations. This feedback will assess the effect, if any, these scrotal phantoms had in preparing them for scanning real patients in the clinical setting. Acknowledgements I would like to thank Gail Rodrigues and Lorena Faundez for helping me in the editing of this article. References 1. 2. Langer S, Kofler JM Jr. A series of teaching phantoms for displaying diagnostic ultrasound image artifacts. J Diag Med Sonogr 1997;13(1):22–7; http://jdm.sagepub.com. Accessed October 15, 2010. De Maeseneer M, De Wilde V, Gosselin R, Osteaux M. The use of phantoms or tissue simulating test objects in the evaluation of imaging methods. JBR–BTR www.csdms.com CAREER OPPORTUNITY Job Title: Clinical Applications Specialist The Clinical Applications Specialist (CAS) position is a sales position that covers demonstrating Zonare Premium Ultrasound systems and accessories, software, transducers and service. It also covers educating and training customers on the “knobology” of the ultrasound systems. Major Responsibilities: Responsibilities include preparing for demonstrations, assisting and performing demonstrations in conjunction with their Zone Sales Representative. Training and educating the customers to use the equipment is also a key part of the job responsibility. The CAS is also responsible for providing support at conferences and seminars. The CAS will also be responsible for supporting the Zone Sales Representative in maintain the customer satisfaction within their territory. Minimum Requirements/Qualifications: s College degree sSouthern Ontario/GTA resident preferred sFluent in English and French desired sFive years of clinical experience sCommercial sales experience preferred sRDMS or RVT registry a must sRDCS registry preferred sStrong communication skills sStrong work ethic sGood organizational skills Please forward resumes to Zonare Medical Systems Ltd Email: [email protected] or Fax: 705 426 1554 The Canadian Journal of Medical Sonography | Fall 2011 27 Original Article Morel-Lavallee Lesion: A Case Report Megan MacNevin About the Author Megan MacNevin is a 4th-year student at the Mohawk/McMaster Institute for Applied Health Sciences, Medical Radiation Science, Ultrasonography Program, in Hamilton, Ontario. She is currently completing her clinical placement at the Ottawa Hospital and will graduate in the spring of 2012. Correspondence may be directed to [email protected]. A Morel-Lavallee lesion is a closed degloving injury, where the skin and subcutaneous tissue are forcibly detached from the underlying fascia by a sudden severe shearing force.1 This type of injury is usually caused by high-speed trauma such as in motor vehicle accidents or severe crushing. The diagnosis of a Morel-Lavallee lesion often occurs some time after the initial injury; this lesion can persist for months before being identified. If the lesion persists for too long without detection, infection may occur, resulting in surgery and a more complicated treatment plan. Imaging modalities, including magnetic resonance imaging and ultrasonography, are the best options for diagnosis. The nature of the cavity fluid should be determined to guarantee the best treatment option for this lesion. Treatment procedures range from minimally invasive compression to extremely invasive open débridement. abdomen. The homogeneous collection was of mixed echogenicity and measured 10 cm × 20 cm × 3 cm in the lateromedial, craniocaudal, and anteroposterior dimensions, respectively. Septations and a fluid-debris level were present throughout the lesion, contributing to the hyperechoic features. Radiologists agreed that these findings were compatible with a closed degloving injury, also known as a Morel-Lavallee lesion. The method of treatment chosen for this case was needle aspiration. Using a 5-French catheter, the first drainage, at the end of July 2009, removed 400 cc of blood. In the following 6 months, the patient attended eight follow-up appointments. In six of these appointments, 70–360 cc of bloody fluid was removed. During the sixth return of the patient, a 16 cm × Case Report A 30-year-old man suffered a dirt biking accident in May of 2009. In July of the same year, he presented with continuous pain and swelling of the right hip. He claimed that the pain had persisted for the previous 2 months, and had been steadily increasing in intensity for the 4 days prior to presentation. Aside from the biking accident in May, the patient did not have a medical history of injury, surgery, or disease. To diagnose the patient’s condition, general radiography and ultrasonography were ordered. The radiograph confirmed that there was no fracture present in the hip or femur. The ultrasound image displayed a large, elongated, lobulated collection in the right hip region superficial to the gluteus maximus and gluteus medius regions (Figures 1 and 2). It appeared to extend between the skin and fascia from the upper thigh region to the mid-axillary line of the lower 28 The Canadian Journal of Medical Sonography | Fall 2011 Figure 1. Ultrasonography of the patient’s right thigh revealed a Morel-Lavallee lesion between the skin and fascia extending from the upper thigh to the mid-axillary line. Note the septations and fluid-debris level. www.csdms.com MacN e v in A B Figure 2. A and B, Transverse and longitudinal sonograms of the right thigh obtained 2 months after the initial injury. A large MorelLavallee lesion is present between the skin and fascia superficial to the gluteus maximus and medius muscles. A fluid-debris level is evident. 1.4 cm × 4.0 cm mostly echogenic hematoma in combination with a small cystic area was found, suggesting that the blood had coagulated and that the case had become more complex. At the following appointment, 360 cc of blood was removed, a positive indication that the lesion had recurred. The final follow-up ultrasonography, in January of 2010, displayed a very slender fluid collection over the right lateral thigh measuring 4.0 cm × 0.4 cm. No drainage was performed at this time as there was very little fluid to remove. The remaining hematoma resolved, and the patient returned to his daily life, with no reoccurrence of the fluid-filled lesion. Discussion As previously stated, a Morel-Lavallee lesion is an abrupt traumatic separation of the skin and subcutaneous fatty tissue from the underlying fascia. This causes a disruption of the vascular and lymphatic plexus perforating through the fascia lata, resulting in a cystic cavity filled with a combination of blood, lymphatic fluid, and necrotic fat. The hemolymphatic tissue is surrounded by granulation tissue that may become organized into a fibrous pseudocapsule – this prevents the reabsorption of fluid and may lead to the persistence of a lesion for months, or years, after an injury.2 A pseudocapsule may also contribute to the lesion’s propensity to recur; the capsule is frequently an indication of a chronic hematoma. The area of degloving is most common in the lower extremities, such as the thigh, greater trochanter, knee, and buttocks (Figure 3). Although rare, such injuries can also occur in the lower back, abdomen, and upper extremities such as the shoulder. A Morel-Lavallee lesion is caused by a blunt tangential force, usually present in high-speed motor vehicle collisions or severe crush injuries involving the entrapment www.csdms.com Figure 3. The most common locations of Morel-Lavallee lesions. Adapted from Hudson et al.3 of a limb between a tire of a motor vehicle and a fixed surface.3 Due to the nature of the cause of this condition, it is usually associated with pelvic and acetabular fractures. However, any blunt trauma without fracture can result in a post-traumatic soft tissue cyst. The Morel-Lavallee lesion goes by the aliases of post-traumatic soft tissue cyst, pseudocyst, Morel-Lavallee extravasation, and Morel-Lavallee effusion.4 Clinical presentation includes variable ecchymoses, commonly known as bruising, an enlarging painful mass, soft fluctuant swelling, a loss of cutaneous sensation, and skin hypermobility.5 Large, more severe lesions may include the dermis and epidermis and can manifest as ischemia of the The Canadian Journal of Medical Sonography | Fall 2011 29 Morel-Lavallee Lesion Figure 4. T1 coronal image of the left thigh shows an encapsulated Morel-Lavallee lesion close to the muscle bellies of the tensor fascia lata and gluteus maximus. Reproduced with permission by Elsevier from Kalaci et al.4 skin, necrosis, or wound sepsis. Local contusions or other signs of injuries such as tire marks or friction burns may be present. Hematomas occur at the site of injury and are usually unilateral, although cases have been reported of severe accidents where the lesion is found bilaterally. There is no finite evidence that Morel-Lavallee lesions appear more frequently in men or women, but it is believed that women are more susceptible because of the difference in the anchorage of their skin to underlying fascia. Hak et al. believe that women have a higher risk of developing a pseudocyst due to the pattern of female fat distribution, which is larger and looser than that in males.6 The Morel-Lavallee extravasation has a slow, progressive growth and is not always recognized during the initial posttraumatic examination. A study by Hudson et al.3 found that in one third of patients, the diagnosis of a closed degloving wound was missed at the initial assessment. If there is any uncertainty about the diagnosis due to patient body habitus or a lack of finite characteristics, a fine-needle aspiration of the area should be performed to confirm the presence of a hematoma. Apart from physical examination, the most useful modalities for diagnosing a post-traumatic soft tissue cyst are magnetic resonance imaging (MRI) and ultrasonography, although computed tomography and general radiography can be used as well. An earlier diagnosis can lead to earlier and more successful treatment. Prolonged diagnosis can lead to severe infections, resulting in invasive surgery and a longer recovery time. Since the identification of this hematoma is often delayed, radiologists should be familiar with the acute and chronic presentations. The appearance of a Morel-Lavallee 30 The Canadian Journal of Medical Sonography | Fall 2011 lesion depends on the age of the lesion, as well as the amount of blood, fat, and lymph tissue within it. The advantages of using MRI are that the morphology and margins of the lesion can be accurately depicted. In acute injuries, the blood clot and debris may be found within an ovoid cavity of T2 hyper-intense fluid. A more chronic injury will have increased or intermediate signal intensity on T1weighted images. As the periphery of a hematoma becomes laden with hemosiderin, a pseudocapsule begins to form and produces a hypo-intense concentric ring on T1 and T2 images. Mellado et al.7 state that there are three main appearances of a pseudocyst on MRI. The first is a homogeneous central hypo-intensity and water-like T2 hyper-intensity relative to skeletal muscle, compatible with a seroma. The second is a homogeneous central T1 and T2 hyper-intensity with a hypo-intense pseudocapsule (Figure 4). The final is a variable central T1 and T2 hyper-intensity, depending on the degree of internal granulation tissue, methemoglobin, hemosiderin, fibrin, and fat necrosis. Ultrasound is a useful tool in diagnosing Morel-Lavallee lesions because it can confirm the presence of the suspected pathology and determine its size, volume, and configuration. In ultrasound images, fluid collections are characterized with regard to echogenicity, homogeneity, shape, margins, and location. Colour and power Doppler are also applied to check for vascularity of the cyst (Figure 5). In a hematoma, there is generally no vascular flow, and this is identified on power and colour Doppler as the absence of colour on the image. For the most part, Morel-Lavallee lesions present as anechoic due to their aqueous nature. Debris and fat necrosis can appear hyperechoic compared with the surrounding fluid and muscle. The interaction of debris and blood in an acute injury are displayed as internal echoes and appear heterogeneous on an ultrasound image. As the hematoma ages, the contents of the lesion organize to form fluid-debris levels that exhibit a homogeneous appearance, which is also a result of the reabsorption of blood and the production of serosanguineous fluid within the cyst. The overall appearance of a lesion can vary according to the stage of internal blood product degradation. If a pseudocapsule develops, the margins are likely to be smooth as opposed to the irregular contour of an acute cyst. The Morel-Lavallee lesion has a variety of shapes, including lobular, flat, and fusiform. Commonly, pseudocysts are located between the severed subcutaneous tissue and underlying fascia, although they have also been found within the subcutaneous fat or muscle. Using ultrasound, Neal et al.8 examined 21 post-traumatic fluid collections. Results found that the acute lesions had a heterogeneous appearance with irregular borders, while chronic lesions were homogeneous with smooth borders. In a study by Kalaci et al.4 an ultrasound examination of the left lateral thigh revealed a large slightly www.csdms.com MacN e v in Figure 5. Transverse ultrasound image displaying a lack of colour in a Morel-Lavallee effusion, indicating that there is no vascular flow in the lesion. Figure 6. Sonogram of the right posterior thigh post-aspiration. The hematoma had been 10 cm × 20 cm ×3 cm. hyperechoic mass with distal acoustic enhancement and hyperechoic papillary extensions from its wall, both of which are consistent with a complex cystic mass. The descriptions of the ultrasound characteristics from the above studies all adhere to those in general guidelines of ultrasound appearances. In diagnosing a Morel-Lavallee lesion, it must be recognized that the appearance of said lesions are extremely various, as proven by the previous studies. The differential diagnoses of the Morel-Lavallee effusion include other post-traumatic injuries, such as fat necrosis or coagulopathy-related hematoma, as well as a hemorrhagic sarcoma and other soft tissue tumours. Biopsy or surgical excision is necessary to exclude a hemorrhagic sarcoma due to the resemblance of these two lesions in imaging characteristics. Careful examination, as well as obtaining a full patient history including prior surgeries, diseases, and trauma, is pertinent to the correct diagnosis. There is no consensus among authors and researchers on the best treatment method. The various methods that have been proposed include compression, aspiration, injection of a sclerosing agent, percutaneous drainage, prolonged surgical drainage, and open débridement. Compression is the least invasive of these procedures and is often used for acute scenarios of minimal severity. Injection of a sclerosing agent is best used for chronic cases in which the hematoma has begun to coagulate. Open débridement is the most invasive treatment option and is performed in chronic or severe cases of tissue necrosis where tissue has to be removed as well as the contents of the lesion. It has been reported that a small, acute lesion without a pseudocapsule can be completely resolved by conservative management, such as compression.8 In an analysis of results, Hudson et al.3 found that conservative surgical intervention, such as compression, could be combined with careful clinical evaluation to produce exceptional results. Matava et al.9 describe the advantages of percutaneous management as the preservation of the remaining cutaneous blood supply as well as an accelerated recovery time due to the small incisions. This method of percutaneous drainage has proved successful in multiple cases, an example of which is the biker from the above case report (Figure 6). An operation of greater extent, such as débridement, separates the subcutaneous tissues from the underlying fascia and disrupts the underlying perforating vessels. Tseng and Tornetta5 as well as Kalaci et al.4 suggest percutaneous drainage in addition to débridement to prevent infection and effectively treat the wound. In comparison, Hak et al.6 recommend thorough débridement of the closed internal degloving injury, and state that percutaneous drainage without débridement of necrotic fat should not be considered because it increases the risk of deep infection. It can be concluded that the treatment of a Morel-Lavallee effusion is a controversial matter with contradicting opinions. Currently, the treatment procedure chosen is at the discretion of the orthopedic surgeon. www.csdms.com Summary Although the Morel-Lavallee lesion was first described in 1853, research is still ongoing due to its uncommon nature. It is clear that this pathology is caused by the subcutaneous tissue being torn away from the underlying fascia as a result of high-speed trauma accidents. If not identified at the time of trauma, patients may present months after the initial injury and healing process with soft tissue swelling or unresolved contour abnormalities. Imaging modalities such as MRI and The Canadian Journal of Medical Sonography | Fall 2011 31 Morel-Lavallee Lesion ultrasonography are the main tools used in diagnosing this condition. The appearance of a Morel-Lavallee lesion in imaging can vary depending on the complexity of the cyst’s contents. There is no preferred treatment method at the present time as opinions of authors, doctors, and researchers differ significantly. A Morel-Lavallee lesion should be detected as early as possible to prevent further infection, as well as longterm consequences, and to ensure effective management. References 1. 2. 3. 4. 5. 6. Phillips T, Jeffcote B, Collopy D. Bilateral Morel-Lavallee lesions after complex pelvic trauma: a case report. J Trauma 2008;65:708–11. Borrero C, Maxwell N, Kavanagh E. MRI findings of prepatellar Morel-Lavallee effusions. Skeletal Radiol 2008;37:451–5. Hudson D, Knottenbelt J, Krige J. Closed degloving injuries: results following conservative surgery. Plast Reconstr Surg 1992;89:853–5. Kalaci A, Karazincir S, Yanat A. 2007. Long-standing Morel-Lavallee lesion of the thigh simulating a neoplasm. Clin Imaging 2007;31:287–91. Tseng S, Tornetta S. Percutaneous management of Morel-Lavallee lesions. J Bone Joint Surg 2006;88:92–96. Hak D, Olson S, Matta J. Diagnosis and management of 7. 8. 9. closed internal degloving injuries associated with pelvic and acetabular fractures: the Morel-Lavallee lesion. J Trauma 1997;42:1046–51. Mellado J, Perez del Palomar L, Diaz L, et al. Longstanding Morel-Lavallée lesions of the trochanteric region and proximal thigh: MRI features in five patients. Am J Radiol 2004;182:1289–94. Neal C, Jacobson J, Brandon C, et al. Sonography of Morel-Lavallee lesions. J Ultrasound Med 2008;27:1077–81. Matava M, Ellis E, Shah N, et al. Morel-Lavallee lesion in a professional American football player. Am J Orthop 2010;29:144–7. Additional Resources Chokshi F, Jose J, Clifford P. Morel-Lavallee lesion. Am J Orthop 2010;39:252–3. Puig J, Pelaez I, Banos J, et al. Long-standing MorelLavallee lesion in the proximal thigh: ultrasound and MR findings with surgical and histopathological correlation. Australas Radiol 2006;50:594–7. Reddix R, Carroll E, Webb L. Early diagnosis of a MorelLavallee lesion using three-dimensional computed tomography reconstructions: a case report. J Trauma 2009;67:57–9. Alberta Health Services is inviting talented Diagnostic Medical Sonographers to join our team AHS values the diversity of the people and communities we serve and is committed to attracting, engaging and developing a diverse and inclusive workforce. Alberta Health Services provides a full spectrum of ultrasound services. You may choose to work in a cuttingedge teaching centre where leading technology, advanced practice, and research go hand-in hand. Or, you may choose to work in a smaller facility providing general ultrasound services to patients in a small community. The staff at Alberta Health Services is appreciated and rewarded with highly competitive salaries. A variety of incentive programs such as relocation packages, temporary accommodation assistance, and bursaries are available to make your move as simple as possible. Alberta Health Services has a variety of full-time, part-time and casual positions available throughout the province. Whether you are seeking work in a large metropolitan area such as Calgary or prefer suburban centres such as Red Deer and Medicine Hat, or communities like Lac la Biche, Westaskiwin and Strathmore, we have an opportunity for you. Requirements: • Active registration with CARDUP and/or ARDMS • Graduate from a two year CARDUP recognized diagnostic ultrasound training program or two years of relevant Canadian sonography experience Contact: Nicole Rashidian, Recruitment Advisor Tel: 403-943-0225 Email: [email protected] Need more reasons? Explore our website to learn more about the great opportunities available: www.albertahealthservices.ca 32 The Canadian Journal of Medical Sonography | Fall 2011 www.csdms.com Announcement Maintaining the Schedule of Unit Values for the Medical Imaging Workload Measurement System Make your recommendation count – and obtain solid data to assist your health service organization in staffing, planning, budgeting, and performance monitoring Arlene L. Thiessen, RN, for the Canadian Institute for Health Information The Canadian Institute for Health Information (CIHI) is an independent, not-for-profit corporation that provides essential information on Canada’s health system and the health of Canadians. CIHI’s unbiased, credible, and comparable data and information enables health leaders to make better-informed decisions. T his article introduces the medical imaging workload measurement system (WMS) continuous quality improvement maintenance cycle for the Canadian Institute for Health Information (CIHI) Standards for Management Information Systems in Canadian Health Service Organizations (MIS Standards). The MIS Standards are a set of national accounting standards used by health service organizations to collect and report financial and statistical data from their daily operations. The MIS Standards were developed to generate better information and measures of health service organizations’ functional centre activity (Figure 1). Medical imaging services that are funded by provincial and territorial ministries of health (except Quebec and Nunavut) rely upon the MIS Standards. Part of the MIS Standards, the WMS is a tool that measures in standardized units of time the volume of activity provided by a specific functional centre, such as ultrasonography or mammography, etc. It serves two main purposes. First, it systematically quantifies workload in specific health care disciplines to assist managers in staffing, planning, budgeting, and performance monitoring. Second, it yields uniform data for external reporting, which permits national and Figure 1. Graphic representation of the data generated by the MIS Standards. Its peer group comparisons. components include accounting principles and applications (white boxes), A schedule of unit values is a list of defined workload measurement system (WMS; light blue box), and the schedule of init activities commonly performed in MI functional values (dark blue box). centres and the unit values associated with each. Its purpose is to facilitate tracking of the handson time, in minutes, required to perform medical imaging time estimates and reviewed by subject matter experts. activities. The unit values are derived from time studies or Maintenance of the MI schedule of unit values enhances good www.csdms.com The Canadian Journal of Medical Sonography | Fall 2011 33 A nnouncement data quality through more representative unit values. During a 2-year project, CIHI redeveloped the 2011 MIS Standards, with particular focus on the MI WMS, to ensure it represented the current environment. In total, 30 volunteers participated, including 11 MI experts who served as Advisory Working Group members. They practised in varied settings ranging from large urban tertiary hospitals to small rural and/or remote hospitals. In all, 40 teleconferences and 4 fullday meetings were conducted. Some of the key changes made to the 2011 MI schedule of unit values include updated terminology, obsolete activities deleted, and new activities created to match scientific advances. Unit values and examination counts were reviewed for accuracy. Activities are more granular, allowing each MI functional centre to customize the workload for a particular examination based on the specific activities performed at the organization. The addendum schedule of unit values for pediatric facilities was reintegrated into the main MI schedule of unit values. A “TBD” (to be determined) value for certain examinations in the 2011 MI schedule of unit values signifies that at the time of publication there were no time studies available nor subject matter experts within the Diagnostic Imaging Advisory Working Group for certain activities. After completing the 2011 maintenance of the schedule of unit values for the clinical laboratory WMS, CIHI recognized that the project was resource-intensive for subject-matter experts in terms of person-hours, time away from their duties, etc. Therefore, in the future, CIHI will leverage electronic survey techniques to elicit feedback from a wider base of subject-matter volunteers. Starting in 2011, CIHI will conduct a biennial maintenance project, which will focus solely on improving the schedule of unit values for MI to keep pace with the ever-changing MI clinical environment. The 2013 MIS Standards will include the results of this project. Following this maintenance cycle, CIHI will evaluate the efficacy of the 2013 MI maintenance project so that the MIS Standards remain as relevant and current as possible. CIHI anticipates a 6-month project involving more than 100 volunteer MI professionals, approximately 10 expert reviewers, and three teleconferences. This fall, CIHI will survey MI professionals to obtain suggested improvements to be made to the schedule of unit values. MI managers/directors, MI technologists, MI information systems (HIS/RIS) professionals, and members from the Diagnostic Imaging Working Group committee from the 2011 project will be invited to participate in the survey. To receive the Medical Imaging survey (for you or for a colleague), for more information, or for specific MI WMS questions, please contact CIHI by e-mail at [email protected] . You can also visit www.cihi.ca > Standards and Data Submission > Standards > MIS Standards. American Registry for Diagnostic Medical Sonography (ARDMS) ® The Globally Recognized Standard of Excellence in Sonography Credibility…ARDMS is the premier worldwide credentialing organization with with nearly nearly 70,000 70,000 certified certified sonography sonography professionals. professionals. organization Experience…ARDMS only only accepts accepts candidates candidates who who meet meet the the rigorous rigorous Experience…ARDMS requirements for for education education and and clinical clinical experience. experience. requirements Growth…ARDMS focuses focuses on on advancing advancing the the Growth…ARDMS sonography profession profession by by setting setting requirements requirements for for sonography continuing medical medical education. education. continuing Visit A Visit ARDMS.org RDMS.org ttoday oday tto oa apply pply o online, nline, ttake ake a p practice ractice e exam xam o orr rreview eview e exam xam ccontent ontent outlines. outlines. Start e Start earning arning o one ne o off tthese hese ccredentials redentials ttoday: oday: RDMS® Registered D Registered Diagnostic iagnostic Medical M edical Sonographer Sonographer RDCS® Registered R egistered D Diagnostic iagnostic Cardiac Sonographer Sonographer Cardiac RVT R VT® Registered R egiste ered V Vascular ascular T echnologist Technologist RPVI® Registered R egistered P Physician hysician in in Vascular Vascular Interpretation Interpretation Accredited A ccredited under under ANSI-ISO ANSI-ISO 17024, 17024, ARDMS ARDMS® ssets ets a standard standard for for e enhanced nhanced p patient atient ssafety afety a and nd h health. ealth. 34 The Canadian Journal of Medical Sonography | Fall 2011 www.csdms.com Now Recruiting Sonographers! If you are interested in joining a stable, growing company that maintains a true dedication to patient care, we’d like to hear from you. To find out more about Sonographer opportunities at CML HealthCare, visit us online at: www.cmlhealthcare.com Discover the Benefits of a Healthy Career Total Rewards CML HealthCare provides comprehensive compensation and benefit packages. Commitment to Patient Care Our team is committed to providing patients with “Care. Confidence. ComfortTM”. Flexibility & Mobility Full time, part time, and casual positions are available to fit your lifestyle. As Canada’s largest provider of diagnostic imaging services, CML HealthCare offers a variety of medical imaging modalities: MRI, CT, Nuclear Medicine, Ultrasound, X-Ray, Mammography, Fluoroscopy, and Bone Densitometry.