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Chapters 33, 35, and Patient Care 33: The Role of Magnetic Resonance Imaging in the Evaluation of Gynecologic Disease 35: Artifacts, Pitfalls Patient Care Holdorf ULTRASOUND OF THE FEMALE PELVIS Contents MRI and Gynecology Artifacts Patient Care MRI and Gynecology MRI is a relatively new technology, which has been in use for little more than 30 years (compared with over 110 years for X-ray radiography). The first MR Image was published in 1973 and the first study performed on a human took place on July 3, 1977. MRI is used to image every part of the body, but is particularly useful in neurological conditions, disorders of the muscles and joints, for evaluating tumors and showing abnormalities in the heart and blood vessels Applications In clinical practice, MRI is used to distinguish pathologic tissue (such as a brain tumor) from normal tissue. One advantage of an MRI scan is that it is harmless to the patient. It uses strong magnetic fields and non-ionizing radiation in the radio frequency range. Compare this to CT scans and traditional Xrays which involve doses of ionizing radiation and may increase the risk of malignancy, especially in a fetus. While CT provides good spatial resolution (the ability to distinguish two structures an arbitrarily small distance from each other as separate), MRI provides comparable resolution with far better contrast resolution (the ability to distinguish the differences between two arbitrarily similar but not identical tissues). MRI can generate cross-sectional images in any plane (including oblique planes). In the past, CT was limited to acquiring images in the axial (or near axial) plane. The scans used to be called Computed Axial Tomography scans (CAT scans). However, the development of multi-detector CT scanners allows the CT scanner to produce data that can be retrospectively reconstructed in any plane with minimal loss of image quality. MRI is also best suited for cases when a patient is to undergo the exam several times successively in the short term, because, unlike CT, it does not expose the patient to the hazards of ionizing radiation. Projectile or missile effect As a result of the very high strength of the magnetic field needed to produce scans (frequently up to 60,000 times the earth's own magnetic field effects), there are several incidental safety issues addressed in MRI facilities. Missile-effect accidents, where ferromagnetic objects are attracted to the center of the magnet, have resulted in injury and death In order to help reduce the risks of projectile accidents, ferrous objects and devices are typically prohibited in proximity to the MRI scanner, with non-ferromagnetic versions of many tools and devices typically retained by the scanning facility. Patients undergoing MRI examinations are required to remove all metallic objects, often by changing into a gown or scrubs. Pregnancy No effects of MRI on the fetus have been demonstrated. In particular, MRI avoids the use of ionizing radiation, to which the fetus is particularly sensitive. However, as a precaution, current guidelines recommend that pregnant women undergo MRI only when essential. This is particularly the case during the first trimester of pregnancy, as organogenesis takes place during this period. The concerns in pregnancy are the same as for MRI in general, but the fetus may be more sensitive to the effects—particularly to heating and to noise. However, one additional concern is the use of contrast agents; gadolinium compounds are known to cross the placenta and enter the fetal bloodstream, and it is recommended that their use be avoided. Despite these concerns, MRI is rapidly growing in importance as a way of diagnosing and monitoring congenital defects of the fetus. MRI without contrast agents is the imaging mode of choice for pre-surgical, in-utero diagnosis and evaluation of fetal tumors, primarily teratomas, facilitating open fetal surgery, other fetal interventions, and planning for procedures to safely deliver and treat babies whose defects would otherwise be fatal. For babies and young children chemical sedation or general anesthesia are the norm, as these subjects cannot be instructed to hold still during the scanning session. Obese patients and pregnant women may find the MRI machine to be a tight fit. Pregnant women may also have difficulty lying on their backs for an hour or more without moving. Cervical Cancer/ Pretherapeutic evaluation of the extent of disease The pre-treatment evaluation of patients with cervical cancer includes physical examination, chest radiography, and intravenous urography (IVU) or cross-sectional imaging (computed tomography scanning or magnetic resonance imaging .) In early-stage disease with a small tumor confined to the cervix, IVU and cross-sectional imaging are not routinely performed because of their relatively low yield. MRI has excellent soft-tissue contrast resolution, which exceeds that of CT scanning and ultrasonography. Consequently, MRI is significantly more valuable than CT and US in the assessment of the size of the tumor, the depth of the cervical invasion, and the extent of the disease (direct invasion of the parametrium, pelvic sidewall, bladder, or rectum) CT scanning and MRI are approximately equivalent, and both are significantly superior to US, in the detection of enlarged lymph nodes Overall, CT scanning and MRI are accurate staging modalities for cervical cancer Furthermore, US is not suited for staging of the full extent of the tumor spread because of the inability of this technique to adequately depict all the potential sites of metastasis or the anatomic regions that contain lymph nodes. Artifacts Pelvis, gravid, and non-gravid uterus Soft-tissue mass vs. urine stream Bowel within the pelvis Bowel-gas artifact Bowel vs. large pelvic cyst Dilated fallopian tubes simulating ovarian cysts Normal sonogram vs. Ovarian torsion Normal prominent bowel vs. ovaries or Paraovarian masses Bowel simulating an ovarian cystic teratomas Pregnancy with a co-existent ovarian carcinoma Nabothian cysts vs. a low-implanted gestational sac Anteflexed uterus vs. mass on transverse view Myomatous disease vs. a hydatidiform mole Broad ligament myoma vs. an ovarian lesion Artifacts homework Bring in the following artifacts/structure classifications as they pertain to gynecology: Posterior acoustic enhancement Edge shadowing Reverberation Posterior acoustic shadowing Slice thickness artifact (Caused by the increased width of the beam beyond the focal zone of the transducer) I call it a “crosseyed beam” artifact in that several different structures are detected by the beam simultaneously. Cystic structure Solid structure Complex structure Patient care Electrical Safety Always use proper grounded electrical devices with threeprong plugs. Avoid the use of extension cords. Do not use any device with frayed cords. Inspect systems routinely. During an ECG, patient should not be grounded, but chassis of ECG machine should be grounded. Patient relations, confidentiality & Assessment In 1996, Congress enacted the Health Insurance Portability and Accountability Act, or HIPAA. The primary purpose was continuity of health insurance coverage if you change jobs, but is also provided for standards for health information transactions and confidentiality and security of patient data. This confidentiality portion will most affect the day-to-day workflow among health care professionals. Privacy Privacy is somewhat different than confidentiality. It refers to individuals’ right to keep some information to themselves and to have it used only with their approval. Under HIPAA, physicians must use and disclose only the minimum necessary amount of patient information needed fro the purpose in question. The institution may use and disclose patient information for treatment, payment, and health care operations without patient authorization. Most other uses and disclosures of patient information require such an authorization. Liability Holds each individual responsible for their actions. Negligence Doing something that a reasonable person will not do or Not doing something that a reasonable person would do. Informed consent Protects doctor from claims of unauthorized procedure. In order to be legally binding, patient must be capable of giving consent (before given morphine, etc.) For invasive procedures, informed consent should be given to operating physician or cardiologist. Interpretation of exams Sonographers cannot provide interpretation of exam to patient. Interpretation must come from physician. Malpractice Claims can be avoided by effective communication between patients and medical personnel. Denial The refusal to acknowledge the existence or severity of unpleasant external realities or internal thoughts and feelings. Initial assessment Including vitals, are used to establish a baseline to compare future results. Wheelchair Moving a patient in or out- brakes engaged, footrests retracted. Foley Catheter An indwelling Foley catheter is a flexible plastic tube that is inserted through the urethra into the bladder, to drain urine. To keep the catheter for slipping out, it as a balloon on the end that is inflated with sterile water or saline once the end is inside the bladder. Keep the urinary drainage bag below the level of he bladder to keep the fluid flowing from the bladder into the collection bag. If the bag is elevated above the bladder, urine will collect in the bladder. Sterilization Sterilization is the elimination of all transmissible agents (such as bacteria and viruses) from a surface or a piece of equipment. This is different from disinfection, where only organisms that can cause disease are removed by a disinfectant. In general, any instrument that enters an already sterile part of the body (such as the blood, or beneath the skin, should be sterilized. This includes equipment like scalpels, hypodermic needles, and artificial pacemakers. Pathogens or infectious agents are biological agents that causes disease or illness to its host. Pathogens disrupt the normal physiology or an animal or plant. The term pathogen is derived from the Greek “Birth of Pain”. The human body has many natural defenses against some of the more common pathogens in the form of the human immune system and by some helpful bacterial present in the human body’s normal flora. However, if the immune system or good bacteria is damaged, pathogenic bacteria that were being controlled can multiply and cause harm to the host. Such cases are called opportunistic infections. Flora- Mucus membranes, such as the intestinal lining, are constantly in contact with environmental organisms and become readily colonized by various microbial species, called flora. Pathogens are responsible fro massive amounts of casualties and have harmful effects on affected groups. (AIDS) Methods of Sterilization Preferred principle for sterilization is through heat and pressure. There are also chemical methods of sterilization. 1. Autoclaves A widely-used method for heat sterilization is the autoclave. Autoclaves use steam heated to 121 degrees C (250 F)and pressure at 103 kPa (15 psi) above atmospheric, for 15 minutes. The steam and pressure transfer heat into organisms to kill them. Useful parameters – time and temperature. 2. Chemical Sterilization Chemicals are also used for sterilization. Although heating provides the most effective way to destroy transmissible agents, it is not always appropriate, because it destroys objects such as fiber optics, electronics, and plastics. Ethylene oxide (EO) gas is commonly used to sterilize objects that cannot survive temperatures greater than 60 degrees C, such as plastics, optics, and electrics. Sepsis Means to soil or dirty. “A” means without. Aseptic means without microorganisms. Aseptic technique refers to practices that reduce post procedure infection in patients by decreasing the likelihood that microorganisms will enter the body during clinical procedures. Sterile Fields A sterile field is an area created by placing sterile towels or surgical drapes around the procedure site and on the stand that holds sterile instruments used during the procedure. The doctor’s sterile area is the only area that should come in contact with the sterile field. Only sterile objects and personnel may be allowed in the sterile field. The sterile area should be draped starting from the area closest to the person and extending outward. While a sterile field is created around a procedure site, items below the level of the draped client are outside the field and are not sterile. A properly gowned and gloved person’s sterile area extends from the chest to the level of the sterile field. Sleeves are sterile from 5 cm ( 2 inches) above the elbow to the cuff. Once a sterile object comes in contact with a non-sterile object or person or with dust or other airborne particles, the object is no longer sterile. If even one non-sterile object or person enters the sterile field, the field is no longer sterile. For example, sterile objects become contaminated if you touch the object with your bare hand, if the object comes into contact with dust or other airborne particles, or if the object is held below the level of the sterile field. The spike of an IV set is sterile and must not come in contact with non-sterile objects. To maintain the Sterile Field 1. Do not place sterile items near 2. 3. 4. 5. open window or doors Place only sterile items within the sterile field Do not contaminate sterile items when opening, dispensing, or transferring them Consider items located below the level of the drape to be unsterile. Do not allow sterile personnel to reach across unsterile areas or to touch unsterile items. 6. Do not allow unsterile personnel to reach across the sterile field or to touch unsterile items. 7. Recognize and maintain the provider’s sterile area. 8. Recognize that the edges of a package containing a sterile item are considered unsterile. 9. Recognize that a sterile or high-level disinfected (HLD) barrier that has been penetrated (wet, cut, or torn) is considered contaminated 10. Be conscious of where your body is at all times, and move within or around the sterile or HLD field in a way that maintains sterility or HLD status. Radiopaque objects: block radiation and appear white on a x-ray film. Bodily Fluid Spills Care must be taken with blood, vaginal secretions, saliva in dental procedures or any body fluid that is visibly contaminated with blood. In addition, care must be taken in situations where it is difficult or impossible to differentiate between body fluids. Universal precautions in emergency situations suggest that all body fluids are potentially infected material (PIM). Infectious fluids can enter our bodies through: Absorption through mucus covering the body openings Through an open, bleeding wound Through damaged areas of the skin, caused by other severe skin diseases. Mucus membranes are much thinner than normal skin. Microscopic cuts in the membranes can allow germs to cross the membrane and enter the blood stream. Also, fluids can be absorbed through these membranes even without any cuts or breaks. Normal skin is much thicker than mucous membranes and provides a good barrier to blood diseases. Infectious fluids cannot be absorbed through skin that is intact. membranes Have these materials on hand for cleaning up spills: A durable container to store the clean up supplies Several biohazard labeled bags Disinfectant-freshly prepared 10% solution of household breach ( 1 part bleach and 9 parts water, or add ½ cup bleach to 1 quart water) or other commercial chlorine or iodine based disinfectant Inert absorbing material (Kitty litter) A small dust pan and hand brush Personal protective equipment, including several pairs of latex gloves, goggles, face masks, coveralls, and paper boots. A roll of paper towels Antiseptic wipes Cleaning a Blood Spill 1. If blood has spilled onto you, it should be thoroughly washed off as soon as possible. If the material has spilled on your clothing and soaked through so that that is skin contact, the cloths must be removed. Following removal, wash those areas where exposure is evident, even to the point of taking a shower. If blood or PIM has come into contact with any of the mucous membranes (eyes, nose, lips) they need to be thoroughly rinsed. If there is contact with open wounds or cracks (chapped skin) in the skin, there is a risk of exposure. Immediately and thoroughly wash your hands with water and soap or an antiseptic cleaner if contaminated with a body fluid. 2. When clean up involves blood or a flat surface, you should first delineate and mark the spill area so that others do not inadvertently enter the area until clean up is complete. 3. Soak the area for at least 20 minutes with a disinfectant (freshly prepared 10% bleach solution). You can be liberal with disinfectant but don’t apply so heavily that it begins to run. 4. Allow at least 20 minutes with a disinfectant to complete the decontamination. You can use the small hand broom and dustpan to clean up the spill. 5. Deposit all clean up material in bio-waste disposal bag and close tightly. The bag should be secured in a biohazard BURN BOX. Carefully remove gloves, coveralls, and boots (if used) and discard in a bio-waste bag. If used, the facemask should also be disposed. Goggles can be disinfected, rinsed, and reused. The dustpan and broom can be disinfected and reused. 6. Record and report the incident to your supervisor.