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The Federal Agency in Health Protection and Social Development The Stavropol State Medical Academy The Department of General Surgery PATIENT’S CASE HISTORY AT SURGICAL CLINIC For Students of General Medicine of the English-speaking Medium Stavropol 2009 УДК 616-618(091) СХЕМА ИСТОРИИ БОЛЕЗНИ В ХИРУРГИЧЕСКОЙ КЛИНИКЕ. (Для студентов лечебного факультета англо-язычного отделения). Ставрополь: Издво СтГМА. – 2009. SHAME OF PATIENT’S CASE HISTORY AT SURGICAL CLINIC (For Students of General Medicine of the English-speaking Medium). Stavropol: St.SMA. – 2009. Cоставители: Владимирова О.В., ассистент кафедры общей хирургии Ставропольской государственной медицинской академии. Линченко В.И., к.м.н., ассистент кафедры общей хирургии Ставропольской государственной медицинской академии. Данное руководство является примерной схемой сбора сведений, необходимых для диагностики заболевания и определения тактики лечения пациентов в хирургических клиниках, написания истории болезни, являющейся основным медицинским и юридическим документом в деятельности врача хирургической клиники. Предназначено для студентов англоязычного отделения медвузов. Рецензенты: Лаврешин П.М., д.м.н., профессор, зав.кафедрой общей хирургии Ставропольской медицинской академии. Знаменская С.В., к.пед.н., доцент, зав.кафедрой иностранных языков с курсом латинского языка, декан факультета иностранных студентов Ставропольской государственной медицинской академии. Рекомендовано к изданию Цикловой методической комиссией по англоязычному обучению иностранных студентов Ставропольской государственной медицинской академии © Ставропольская государственная медицинская академия, 2009 INTRDUCTION 2 Obtaining an accurate history is the critical first step in determining the etiology of a patient's problem. A large percentage of the time, you will actually be able to make a diagnosis based on the history alone. The value of the history, of course, will depend on your ability to elicit relevant information. Your sense of what constitutes important data will grow exponentially in the coming years as you gain a greater understanding of the pathophysiology of disease through increased exposure to patients and illness. That is, an ability to listen and ask common-sense questions that help define the nature of a particular problem. It does not take a vast, sophisticated fund of knowledge to successfully interview a patient. In fact seasoned physicians often lose site of this important point, placing too much emphasis on the use of testing while failing to take the time to listen to their patients. Successful interviewing is for the most part dependent upon your already well developed communication skills. by recorder GettingStarted: Always introduce yourself to the patient. Then try to make the environment as private and free of distractions as possible. This may be difficult depending on where the interview is taking place. The emergency room or a non-private patient room are notoriously difficult spots. Do the best that you can and feel free to be creative. If the room is crowded, it's OK to try and find alternate sites for the interview. It's also acceptable to politely ask visitors to leave so that you can have some privacy. If possible, sit down next to the patient while conducting the interview. Remove any physical barriers that stand between yourself and the interviewee (e.g. put down the side rail so that your view of one another is unimpeded... though make sure to put it back up at the conclusion of the interview). These simple maneuvers help to put you and the patient on equal footing. Furthermore, they enhance the notion that you are completely focused on them. You can either disarm or build walls through the speech, posture and body languarge that you adopt. Recognize the power of these cues and the impact that they can have on the interview. While there is no way of creating instant intimacy and rapport, paying attention to what may seem like rather small details as well as always showing kindness and respect 3 can go a long way towards creating an environment that will facilitate the exchange of useful information. If the interview is being conducted in an outpatient setting, it is probably better to allow the patient to wear their own clothing while you chat with them. At the conclusion of your discussion, provide them with a gown and leave the room while they undress in preparation for the physical exam. If you were not aware that coronary-based ischemia causes a symptom complex identical to what the patient is describing, you would have no idea what further questions to ask. That's OK. With additional experience, exposure, and knowledge you will learn the appropriate settings for particular lines of questioning. You will undoubtedly forget to ask certain questions, requiring a return visit to the patient's bedside to ask, "Just one more thing." Don't worry, this happens to everyone! You'll get more efficient with practice. Dealing With Your Own Discomfort: Many of you will feel uncomfortable with the patient interview. This process is, by its very nature, highly intrusive. The patient has been stripped, both literally and figuratively, of the layers that protect them from the physical and psychological probes of the outside world. Furthermore, in order to be successful, you must ask in-depth, intimate questions of a person with whom you essentially have no relationship. This is completely at odds with your normal day to day interactions. There is no way to proceed without asking questions, peering into the life of an otherwise complete stranger. This can, however, be done in a way that maintains respect for the patient's dignity and privacy. In fact, at this stage of your careers, you perhaps have an advantage over more experienced providers as you are hyper-aware that this is not a natural environment. Many physicians become immune to the sense that they are violating a patient's personal space and can thoughtlessly over step boundaries. Avoiding this is not an easy task. Listen and respond appropriately to the internal warnings that help to sculpt your normal interactions. 4 STAVROPOL STATE MEDICAL ACADEMY Department of General Surgery The head of the department __________________ Lavreshin P.M. Instructor ______________________ CASE HISTORY Name, surname of the patient Age Clinical diagnosis Complications Concomitant diseases Student Name, Surname Group № Date of observation till… from… STAVROPOL PASPORT INFORMATION 5 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. Name, surname of the patient Sex Age Place of employment, profession Place of living, address Family, relatives Delivery date and time Date of discharged from hospital Clinical diagnosis Complications of fundamental illness Concomitant diseases (present on the moment of examination) SUBJECTIVE EXAMINATION 1. Chief Complaints Usually recorded as a short statement Record in the patient’s own words Not your technical translation of the patient’s words Short characteristic of complaints First writings most important (specific) complaints. If a few complaints start simultaneously, list them in order of severity. Detail complaints. Be sure to always address the chief complaint when counseling the patient at the end of the examination This question must be answered prior to the end of the exam. Exceptions: ath) Record CC in patient's own words - don't intrepret 2. Medical [case] history This history commences from the beginning of the first symptom and extends to the time of examination. - Find out exact time of the beginning of disease and complaints. 6 Single most important quesiton: "Why have you come today, not earlier?" - The mode of onset of the symptoms — whether sudden or gradual, as well as the cause of onset, if at all present; - The progress of the disease with evolution of symptoms in the exact order of their occurrence; and lastly; - The treatment which the patient might have received — the mode of treatment and the doctor, who has treated. To know the mode of onset, the patient is asked, "How did the trouble start?" To know the progress of the disease, the patient is asked, "What is the next thing that happened?" or any such relevant question as the type of case may necessitate. This should be recorded in the patient's own language and not in scientific terms. The patient should be allowed to describe his own story of symptoms. They know more about their complaints than the doctors. But if they wander too far from the point, they should be put such questions as to bring them back into the matter. Never ask the question— "What is the matter?" The patient will obviously tell you his or another doctor's diagnosis, which you do not want to know. 'Leading questions' should not be put to the patients. By this, it is meant that questions, which yield only one answer, should not be asked. As for example, if the patient is asked like this — "Doesn't the pain move to the inferior angle of the right scapula?" Obviously a well-behaved patient will answer "Yes" to please you. So the question should be such that it leaves the patient with a free choice of answer. As for example, the question should be, "Does the pain ever move?" If the patient says, "Yes", you should ask, "Where does it go?" So the questions should not necessarily be 'leading', but to help the patient to narrate the different aspects of his symptoms to arrive at a definite diagnosis. Sometimes negative answers are more valuable in arriving at a diagnosis and should never be disregarded. As for example, in case of a sinus on the cheek, absence of the history of watery discharge at the time of meals at once excludes the possibility of a parotid fistula. 4. Past History. All the diseases suffered by the patient, previous to the present one, should be noted and recorded in a chronological order. There should be mention of dates of their occurrence and the duration. These diseases may not have any relation with the present disease. Particular attention is paid to the diseases like diabetes, diphtheria, rheumatic fever, bleeding tendencies, tuberculosis, syphilis, gonorrhoea, 7 tropical diseases, asthma etc. Under this heading, the students should not forget to mention any of the previous operations or accidents, which the patient might have sustained. The dates and the types of operations should be mentioned in a chronological order. Drug history.— The patient should be asked about all the drugs he was on. Besides the fact that this will help to give a clue to the present illness or in the subsequent treatment, it has tremendous importance from anaesthetic point of view. Special enquiry should be made about steroids, insulin, antihypertensives, diuretics, ergot derivatives, monoamine oxidase inhibitors, hormone replacement therapy, contraceptive pills etc. History of allergy.— This is very important and should not be missed under any circumstances, while taking history of a patient. The patient should be asked whether he or she is allergic to any medicine or die. It should be noted with red type on the cover of the history sheet. The students should make it a practice and they will definitely find that this valuable practice will save many catastrophies. Personal history.— Under this heading, the patient's habit of smoking (cigarettes, cigar or pipe and the frequency), drinking of alcohol (quality and quantity), diet (regular or irregular, vegetarian or non-vagetarian, takes spicy food or not etc.) are noted. It is also enqliired about the marital status of the individual — whether married or single, a widow or a widower. In women, the menstrual history must be recorded perfectly—whether the patient is having regular menstruation or not, the days of menstruation, whether any pain is associated with menstruation or not and last date of menstruation. The number of pregnancies and miscarriages are noted with their dates, — whether the deliveries were normal or not, whether the patient had Caesarean section or not and if so, for what reason. The patient.is also asked whether there is any white discharge per vaginam or not. Family history.— This part of the history is very important. Many diseases do recur in families. Haemophilia, tuberculosis, diabetes, essential hypertension, peptic ulcer, majority of the cancers particularly the breast cancer and certain other diseases like fissure-in-ano, piles etc. run in families. So the students must not forget to enquire about other members of the family, such as about parents if they are still alive. How are they maintaining their healths? Did they suffer from any major ailments? If they are dead, what were the causes of their deaths? You should also enquire about the brothers and sisters and children of the patient. History of immunization.— Children should be asked whether they have been immunised against diphtheria, tetanus, whooping cough, poliomyelitis, small pox, tuberculosis etc. 8 OBJECTIVE EXAMINATION 5. PHYSICAL EXAMINATION This includes General survey, General examination and Local examination. - General Survey. Under this heading comes general assessment of: - illness, - mental state, - intelligence, - build, - state of nutrition, - the attitude, - the decubitus (position in bed), - colour of the skin, - skin erruptions if present, - pulse, - respiration, - temperature. Physical examination starts when the patient enters the clinic. It requires daylight and of course a co-operative patient. In artificial light, one may miss the faint yellow tinge of slight jaundice. For complete examination, the patient should be asked to take off all his clothes and covered by only a dressing gown. GENERAL ASSESSMENT OF ILLNESS.— This is very important and should be assessed in the first opportunity. In case of severely ill patients, one should cufdown the wastage of time to know other less important findings. The doctor should hasten into the treatment after rapidly going through the local examination to come to a probable diagnosis and to find out those signs which may help him to institute proper treatment. MENTAL STATE and INTELLIGENCE.— In case of chronically ill patients, the doctor should always assess the mental state and intelligence of the individual. An intelligent patient will give a very good history on which the doctor can rely. On the other hand the doctor should not rely wholly on the history from the patient with very low intelligence. BUILD and STATE OF NUTRITION.— Besides the fact that a few endocrine abnormalities become obvious from the build of the patient, a hint to clinical diagnosis may be achieved from a look on the build of the patient. As for example, a cachectic patient suffering from an abdominal discomfort with a lump, is probably suffering from carcinoma of some part of the G.I. tract. 9 ATTITUDE.— This is very important and gives valuable information to arrive at a diagnosis. Patients with pain due to peritonitis lie still, whereas patients with colicky pain become restless and toss on the bed. Meningitis of the neck will show neck retraction and rigidity. An old patient after a fall, when lies helpless with an everted leg, possibility of fracture of the neck of the femur becomes obvious. DECUBITUS.— This means the position of the patient in bed. This is sometime informatory, e.g. in cerebral irritation the patient lies curled upon his side away from light. COLOUR OF THE SKIN.— So far as the colour of the skin is concerned, broadly the students should try to find out the presence of pallor, cyanosis or jaundice. Pallor of the skin is seen in massive haemorrhage, shock and intense emotion. Anaemic patients are also pale. One should look at the lower palpebral conjunctiva, nail bed etc. for pallor. Cyanosis, i.e. bluish or purplish tint of the skin will be obvious if one tries to find this out in nail . bed, ear lobule-, tip of the nose etc. There are a number of conditions, which may lead to cyanosis, but broadly speaking inadequate oxygenation in the lungs of the venous blood, which flows through pulmonary artery to the lungs, will produce this condition. This may be due to diseases in the lungs or due to some congenital abnormalities, which have by-passed the blood from the pulmonary artery to the aorta. Jaundice is due to icteric tint of the skin, which varies from faint yellow of viral hepatitis.to dark olive greenish yellow of obstructive jaundice. This is due to the presence of excess of lipid-soluble yellow pigments (mostly the bile pigments) in the plasma. The places where one should look for jaundice are — sclera of the eyeball, for this the patient is asked to look at his feet when the surgeon keeps the palpebral fissure wide open by pulling up the eyelid, nail bed, lobule of the ear, tip of the nose, under-surface of the tongue etc. SKIN ERRUPTION.— Under this heading comes macules, papules, vesicles, pustules, wheals etc. Macules.— i.e. an alteration in the colour of the skin, which is seen but not felt. It may be due to capillary naevi or erythemas which disappear on pressure, whereas purpuric macules do not blanch when pressed. Papules — are solid projections from the surface of the skin. It may be epidermal papule, e.g. a wart or a dermal papule, which will become less prominent if the skin is stretched, e.g: a granuloma of tuberculosis, reticulosis or sarcoidosis. Vesicles — are elevations of horny layer of the epidermis by collection of transparent or milky fluid within it. Pustules — are similar elevations of the 10 skin as vesicles, but these contain pus instead of fluid within it. Wheal — is a flat oedematous elevation of the skin frequently accompanied by itching. It is the typical lesion of urticaria and may be seen in sensitive persons provoked by irritation of the skin. PULSE.— This is an important index of severity of illness. Pulse gives a good indication as to the severity of acute appendicitis. Generally it gives a good indication of the cardio-vascular condition of the patient. Abnormalities of the heart and the vascular system, e.g. hypertension and hypotension are also revealed in pulse. Shock, fever and thyrotoxicosis are a few conditions, which are well reflected in pulse. In pulse one should not only count the pulse rate, but alio assess theregularity and volume of the pulse. RESPIRATION.— The students will gradually learn the importance of respiration as a finding not only for diagnosis, but also to assess the condition of the patient under anaesthesia and in early postoperative days. Tachypnoea (fast breathing) is seen in fever, shock, hypoxia, cerebral disturbances, metabolic acidosis, tetany, hysteria etc. Slow and deep respiration is an ominous sign in cerebral compression. TEMPERATURE.— This is normally taken in the mouth or in the axilla of the patient. The temperature of the mouth is about 1° F higher than that of the axilla. Fever or high temperature is come across in various conditions, which the students will be more conversant in medical ward. But broadly, the students should know that there are three types of fever — the continued, the remittent and the intermittent. When the fever does not fluctuate for more than 1°C during 24 hours, but at no time touches the normal, it is described as continued. When the daily fluctuations exceed 2° C it is remittent and when the fever is present only for a few hours during the day, it is called intermittent. When a paroxysm of intermittent fever occurs daily, it is called quotidian, when on alternate days it is called tertian and when two days intervene between the consecutive attacks, it is called quartan. - Local examination. This is the most important part in the physical examination as a careful local examination will give a definite clue to arrive at a diagnosis. By 'local examination' we mean examination of the affected region. This should be done by: 1. inspection (looking at the affected part of the body), 2. palpation (feeling of the affected part by the hands of the surgeon), 3. percussion (listening to the tapping note with a finger on a finger placed on the affected part), 4. auscultation (listening to the sounds produced within the body with the help of a stethoscope), 11 5. movement (of the joints concerned), measurement ( of the part 6f the body concerned) and 6. examination of the lymph nodes draining the affected area. Detailed description of these examinations are discussed in subsequent chapters. Inspection of the part should be carried out after complete exposure. It should be compared with the corresponding normal side, whenever possible. The importance of proper inspection cannot be over-emphasized, as many of the surgical conditions can be diagnosed by looking at it with well-trained eyes. It is said that eyes do not see what mind does not know. So a thorough knowledge of the whole subject is essential before one can train one's eyes for such good inspection. Palpation will not only corroborate the findings seen in inspection, but also added informations with trained hands may not require any. further examination to come to a diagnosis. Percussion and Auscultation are not so important as in the medical side for clinical diagnosis of surgical diseases. These are only important in a few surgical conditions, which will be discussed later in appropriate chapters. Movements and Measurement are important particularly in orthopaedic cases, in fractures and in injuries of different nerves. Local examination is never complete without the examination of the draining lymph nodes. More often than not the students forget to do this valuable examination and fail to diagnose many important cases._ - General examination. In chronic cases, one should always examine the patient as a whole, after completing the local examination. In acute cases, this examination may be omitted to save the valuable time. But even in acute cases, certain general examinations should be carried out either for anaesthetic sake or for treatment point of view. General examination is required mainly for the following purposes: 1) For the diagnosis and differential diagnosis.— For example, in case of retention of urine, one should examine the knee and ankle jerks and pupillary reflexes (Argyll Robertson pupil) to come to a diagnosis of Tabes dorsalis. Similarly examination of the chest or spine should be carried out in an otherwise obscure abdominal pain to find out basal pleurisy or caries spine as the cause of pain. Sometimes the patient complains of pain in the knee while the pathology lies in the hip joint. Cases are on record when teen-aged boy with the complain of pain in the right iliac fossa was referred to the hospital 12 by the general physician as a case of acute appendicitis. Only after examination of the scrotum, the surgeon found torsion of the testis as the cause of pain and not appendicitis. 2) For selecting the type of anaesthetic.— The anaesthetist should always examine the patient generally, particularly the heart and lungs to select the proper anaesthetic. Sometimes the operation should be performed under local anaesthesia in old and cardiac patients. 3) To determine the nature of the operation.— In case of an inguinal hernia, one should examine the chest to exclude a cause of chronic cough, for enlarged prostate or for stricture of urethra as an organic cause of an obstruction to the outflow of urine and to exclude constipation as cause for increased abdominal pressure to initiate hernia. So patients with these conditions, if operated on, will definitely come back with recurrence of hernia. At the same time, the surgeon should look for the tone of the abdominal muscles to determine whether herniorrhaphy or hernioplasty will give the best result. 4) To determine the prognosis.— In a case of gastric cancer, if general examination reveals involvement of the supraclavicular glands, the prognosis is obviously grave. Similarly cancer of the breast, if shows secondary metastases in bones and lungs, is diagnosed to be in the last stage. A list is given below to remember the points to be examined under the heading of 'general examination': Head and neck 1) Cranial nerves — particularly the 3rd, 4th, 5th, 6th, 7th, 9th, 11th and 12th cranial nerves should be examined, if necessary. 2) Eyes.— Tests are done to know the visual field, condition of the conjunctiva and pupils (equality, reaction to light and accommodation reflex), movements of the eye and ophthalmic examination of the fundi. 3) Mouth and pharynx.— Teeth and gum, movement of soft palate, the tongue and its under-surface, tonsils and lips for colour, pigmentation and eruptions. 4) Movements of the neck, neck veins and lymphatic glands of the neck, carotid pulses and the thyroid gland. Upper limbs 1) General examination of the arms and hand with particular reference to their vascular supply and nerve supply (Power, tone, reflexes and sensations). 2) Axillae and lymph nodes. 3) Joints. 4) Finger nails—clubbing or koilonychia. Thorax 13 1) Type of chest. 2) Breasts. 3) Presence of any dilated vessels and pulsations. 4) Position of the trachea. 5) Apex beat. 6) Lungs—as a whole, i.e. inspection, palpation, percussion and auscultation. 7) The heart should be examined as a whole, i.e. palpation, percussion and auscultation. Abdomen 1) Abdominal wall—position of the umbilicus, presence of scars, dilated vessels etc. 2) Abdominal reflexes. 3) Visible peristalsis or pulsation. 4) Generalised palpation, percussion and auscultation. 5) Hernial orifices. 6) Genitalia. 7) Inguinal glands. 8) Rectal examination. 9) Gynaecological examination , if required. Lower limbs 1) General examination of legs and feet— with particular reference to the vascular supply and nerve supply (Power, tone, reflexes and sensation). 2) Varicose vein. 3) Oedema. 4) Joints. Examination of the external genitalia Urine, stool should be examined by naked eye and under microscope, if required. 6. PROVISIONAL DIAGNOSIS At this stage the clinician should be able to make a provisional diagnosis. He should also keep in mind the differential diagnosis. He will now require a few investigations to come to the proper clinical diagnosis. The students should know how to diagnose common diseases first and then he should think for possibility of rare diseases. A word of the cautiori will not be irrelevant here that 'if you diagnose a rare disease, you will be rarely correct'. 7. SPECIAL INVESTIGATIONS 14 Besides the routine examination of the blood, urine and stool, a few special investigations depending upon the provisional diagnosis will be required to arrive at a proper diagnosis. These are discussed in details in appropriate chapters. 8.CLINICAL DIAGNOSIS After getting the reports of special investigations, the clinician should be able to give proper clinical diagnosis. By this we mean that not only the ailing organ is identified, but the type of pathological process at work and its extent in different directions is also understood. As for example, in carcinoma of the breast, one should mention under this heading the clinical stage of the disease and the various structures involved in metastasis. Similarly in case of inguinal hernia, the clinician should not only mention that whether it is direct or indirect, reducible or irreducible, but also should mention its content— either the intestine or omentum or a portion of urinary bladder. 9. Tactic of treatment: - treatment of pathology (all possible types of treatment – from literature) - treatment of patient (individual case) 10. Dairys of observation: - condition of the patient, dynamic. - general examination in short form - local examination - dynamic of wounds, local signs. 11. Indications for operation, contraindications. 12. Detailed operative notes. 13. Postoperative observation: - postoperative complications - condition of the patient, dynamic. - general examination in short form - local examination - dynamic of wounds, local signs. 14. Prognosis: - prognosis for a disease - prognosis for life 15 - prognosis for working Immediate prognosis Long-term prognosis SPECIAL INVESTIGATIONS Fluoroscopy Fluoroscopy produces real-time images of internal structures of the body in a similar fashion to radiography, but employs a constant input of x rays, at a lower dose rate. Contrast media, such as barium, iodine, and air are used to visualize internal organs as they work. Fluoroscopy is also used in imageguided procedures when constant feedback during a procedure is required. An image receptor is required to convert the radiation into an image after it has passed through the area of interest. Early on this was a fluorescing screen, which gave way to an Image Amplifier (IA) which was a large vacuum tube that had the receiving end coated with cesium iodide, and a mirror at the opposite end. Eventually the mirror was replaced with a TV camera. Magnetic resonance imaging (MRI) A magnetic resonance imaging instrument (MRI scanner) uses powerful magnets to polarise and excite hydrogen nuclei (single proton) in water molecules in human tissue, producing a detectable signal which is spatially encoded resulting in images of the body. In brief, MRI involves the use of three kinds of electromagnetic field: a very strong (of the order of units of teslas) static magnetic field to polarize the hydrogen nuclei, called the static field; a weaker time-varying (of the order of 1 kHz) for spatial encoding, called the gradient field(s); and a weak radio-frequency (RF) field for manipulation of the hydrogen nuclei to produce measurable signals, collected through an RF antenna. Like CT, MRI traditionally creates a 2D image of a thin "slice" of the body and is therefore considered a tomographic imaging technique. Modern MRI instruments are capable of producing images in the form of 3D blocks, which may be considered a generalisation of the single-slice, tomographic, concept. Unlike CT, MRI does not involve the use of ionizing radiation and is therefore not associated with the same health hazards; for example there are no known long term effects of exposure to strong static fields (this is the subject of some debate; see 'Safety' in MRI) and therefore there is no limit on the number of scans to which an individual can be subjected, in contrast with X-ray and CT. However, there are well identified health risks associated with tissue heating from exposure to the RF field and the presence of implanted 16 devices in the body, such as pace makers. These risks are strictly controlled as part of the design of the instrument and the scanning protocols used. CT and MRI being sensitive to different properties of the tissue, the appearance of the images obtained with the two techniques differ markedly. In CT, X-rays must be blocked by some form of dense tissue to create an image, therefore the image quality when looking at soft tissues will be poor. While any nucleus with a net nuclear spin can be used, the proton of the hydrogen atom remains the most widely used, especially in the clinical setting, since it is so ubiquitous and returns much signal. This nucleus, present in water molecules, allows excellent soft-tissue contrast. MRI, or "NMR imaging" as it was originally known, has only been in use since the early 1980s. Effects from long term, or repeated exposure, to the intense static magnetic field are not known. Positron emission tomography (PET) Positron emission tomography is primarily used to detect diseases of the brain and heart. Similarly to nuclear medicine, a short-lived isotope, such as 18F, is incorporated into a substance used by the body such as glucose which is absorbed by the tumor of interest. PET scans are often viewed alongside computed tomography scans, which can be performed on the same equipment without moving the patient. This allows the tumors detected by the PET scan to be viewed next to the rest of the patient's anatomy detected by the CT scan. Projection radiography Radiographs, more commonly known as x-rays, are often used to determine the type and extent of a fracture as well as for detecting pathological changes in the lungs. With the use of radio-opaque contrast media, such as barium, they can also be used to visualize the structure of the stomach and intestines this can help diagnose ulcers or certain types of colon cancer. Echocardiography Echocardiography is used to diagnose cardiovascular diseases. In fact, it is one of the most widely used diagnostic tests for heart disease. It can provide a wealth of helpful information, including the size and shape of the heart, its pumping capacity and the location and extent of any damage to its tissues. It is especially useful for assessing diseases of the heart valves. It not only allows doctors to evaluate the heart valves, but it can detect abnormalities in the pattern of blood flow, such as the backward flow of blood through partly closed heart valves, known as regurgitation. By assessing the motion of the heart wall, echocardiography can help detect the presence and assess the severity of coronary artery disease, as well as help determine whether any chest pain is related to heart disease. Echocardiography can also help detect 17 hypertrophic cardiomyopathy, in which the walls of the heart thicken in an attempt to compensate for heart muscle weakness. The biggest advantage to echocardiography is that it is noninvasive (doesn't involve breaking the skin or entering body cavities) and has no known risks or side effects. - Transthoracic echocardiogram - Transesophageal echocardiogram - 3-dimensional echocardiography Electrocardiogram Is a recording of the electrical activity of the heart over time produced by an electrocardiograph, usually in a noninvasive recording via skin electrodes. Endoscopy Endoscopy is a minimally invasive diagnostic medical procedure that is used to assess the interior surfaces of an organ by inserting a tube into the body. The instrument may have a rigid or flexible tube and not only provide an image for visual inspection and photography, but also enable taking biopsies and retrieval of foreign objects. Endoscopy is the vehicle for minimally invasive surgery, and patients may receive conscious sedation so they do not have to be consciously aware of the discomfort. Endoscopy can involve: The gastrointestinal tract (GI tract): - esophagus, stomach and duodenum (esophagogastroduodenoscopy) small intestine colon (colonoscopy, proctosigmoidoscopy) Bile duct: endoscopic retrograde cholangiopancreatography (ERCP), duodenoscopeassisted cholangiopancreatoscopy, intraoperative cholangioscopy - The respiratory tract - The nose (rhinoscopy) - The lower respiratory tract (bronchoscopy) - The urinary tract (cystoscopy) - The female reproductive system - The cervix (colposcopy) - The uterus (hysteroscopy) - The Fallopian tubes (Falloscopy) Normally closed body cavities (through a small incision): The abdominal or pelvic cavity (laparoscopy) The interior of a joint (arthroscopy) Organs of the chest (thoracoscopy and mediastinoscopy) During pregnancy - The amnion (amnioscopy) 18 - The fetus (fetoscopy) Plastic Surgery - Panendoscopy (or triple endoscopy) Combines laryngoscopy, esophagoscopy, and bronchoscopy. Diagnostic sonography (ultrasonography) is an ultrasound-based diagnostic imaging technique used to visualize muscles and internal organs, their size, structures and possible pathologies or lesions. Obstetric sonography is commonly used during pregnancy. Computed tomography (CT) is a medical imaging method employing tomography. Digital geometry processing is used to generate a threedimensional image of the inside of an object from a large series of twodimensional X-ray images taken around a single axis of rotation. The word "tomography" is derived from the Greek tomos (slice) and graphein (to write). A form of tomography can be performed by moving the X-ray source and detector during an exposure. Anatomy at the target level remains sharp, while structures at different levels are blurred. By varying the extent and path of motion, a variety of effects can be obtained, with variable depth of field and different degrees of blurring of 'out of plane' structures. Dynamic volume CT 320-slice CT scanner, with its 16 cm anatomical coverage, can scan entire organs such as heart and brain, in just one single rotation, thereby also enabling dynamic processes such as blood flow and function to be observed. Whereas patients exhibiting symptoms of a heart attack or stroke have until now normally had to submit to a variety of examinations preparatory to a precise diagnosis, all of which together took up a considerable amount of time, with dynamic volume CT this can be decreased to a matter of minutes and one single examination. Functional imaging can thus be performed rapidly, with the least possible radiation and contrast dose combined with very high precision. Scout/pilot/topogram A Scout image is used in planning the exam and to establish where the target organs are located. The beginning and end of the scan are set by the target region and the location of the patient on the table. Once the Scout image is created it is used to determine the extent of the desired Axial/Helical scan. During the Scout scan the gantry is rotated to a fixed position and the table is translated as x-ray is delivered. The image appears similar to a radiograph. Axial 19 In axial "step and shoot" acquisitions each slice/volume is taken and then the table is incremented to the next location. In multislice scanners each location is multiple slices and represents a volume of the patient anatomy. Cine A cine acquisition is used when the temporal nature is important. This is used in Perfusion applications to evaluate blood flow, blood volume and mean transit time. Cine is a time sequence of axial images. In a Cine acquisition the cradle is stationary and the gantry rotates continuously. Xray is delivered at a specified interval and duration. DRR A Digitally Reconstructed Radiograph is a simulation of a conventional 2D x-ray image, created from computed tomography (CT) data. A radiograph, or conventional x-ray image, is a single 2D view of total x-ray absorption through the body along a given axis. Two objects (say, bones) in front of one another will overlap in the image. By contrast, a 3D CT image gives a volumetric representation. (Earlier CT data sets were better thought of as a set of 2D cross sectional images.) Sometimes one must compare CT data to a classical radiograph, and this can be done by comparing a DRR based on the CT data. DRRs are created by summing CT intensities along a ray from each pixel to the simulated x-ray source. Electron beam CT Electron beam tomography (EBCT) was introduced in the early 1980s, by medical physicist Andrew Castagnini, as a method of improving the temporal resolution of CT scanners. Because the X-ray source has to rotate by over 180 degrees in order to capture an image the technique is inherently unable to capture dynamic events or movements that are quicker than the rotation time. Helical or spiral CT In helical CT the X-ray source are attached to a freely rotating gantry. During a scan, the table moves the patient smoothly through the scanner; the name derives from the helical path traced out by the X-ray beam. It was the development of two technologies that made helical CT practical: slip rings to transfer power and data on and off the rotating gantry, and the switched mode power supply powerful enough to supply the X-ray tube, but small enough to be installed on the gantry. The major advantage of helical scanning compared to the traditional shootand-step approach, is speed; a large volume can be covered in 20-60 seconds. This is advantageous for a number or reasons: 1) often the patient can hold their breath for the entire study, reducing motion artifacts, 2) it allows for more optimal use of intravenous contrast enhancement, and 3) the study is quicker than the equivalent conventional CT permitting the use of higher 20 resolution acquisitions in the same study time. The data obtained from spiral CT is often well-suited for 3D imaging because of the lack of motion misregistration and the increased out of plane resolution. These major advantages led to the rapid rise of helical CT as the most popular type of CT technology. Multislice CT Multislice CT scanners are similar in concept to the helical or spiral CT but there are multiple detector rings. The major benefit of multi-slice CT is the increased speed of volume coverage. This allows large volumes to be scanned at the optimal time following intravenous contrast administration; this has particularly benefited CT angiography techniques - which rely heavily on precise timing to ensure good demonstration of arteries. Dual-source CT Dual sources increase the temporal resolution by reducing the rotation angle required to acquire a complete image, thus permitting cardiac studies without the use of heart rate lowering medication, as well as permitting imaging of the heart in systole. The use of two x-ray units makes possible the use of dual energy imaging, which allows an estimate of the average atomic number in a voxel, as well as the total attenuation. This permits automatic differentiation of calcium (e.g. in bone, or diseased arteries) from iodine (in contrast medium) or titanium (in stents) - which might otherwise be impossible to differentiate. It may also improve the characterization of tissues allowing better tumor differentiation. This system simply uses 2 separate 32 slice dedectors with 2 separate X-Ray tubes with flying focus. The generated data is 64 axial images per rotation (only in cardiac scans). 256+ slice CT The technology currently remains in a development phase but has demonstrated the potential to significantly reduce radiation exposure by eliminating the requirement for a helical examination in both cardiac CT angiography and whole brain perfusion studies for the evaluation of stroke. Inverse geometry CT Inverse geometry CT (IGCT) is a novel concept which is being investigated as refinement of the classic third generation CT design. The conventional third-generation CT geometry uses a point source of X-rays, which diverge in a fan beam to act on a linear array of detectors. In multidetector computed tomography (MDCT), this is extended in 3 dimensions to a conical beam acting on a 2D array of detectors. The IGCT concept, conversely, uses an array of highly collimated X-ray sources which act on a point detector. By using a principle similar to electron beam tomography (EBCT), the 21 individual sources can be activated in turn by steering an electron beam onto each source target. Peripheral Quantitative Computed Tomography (pQCT) pQCT-measurement at distal radius (cross-sectional image) pQCT or QCT devices are optimized for high precision measurements of physical properties of bone such as bone density and bone geometry. In comparison to the commonly used DXA system which measures bone mass only (BMD), QCT systems can determine bone strength as a mechanical property and the resulting fracture risk. Hence one outcome parameter is the Stress-Strain Index (SSI) comparing bone strength to results of three point bending tests commonly used for mechanical material tests. Typical application is Osteoporosis diagnostics where single slices at the Tibia or the Radius are measured resulting in a very low local Radiation dose of 1-2 μSv. X-ray tomography X-ray Tomography is a branch of X-ray microscopy. A series of projection images are used to calculate a three dimensional reconstruction of an object. The technique has found many applications in materials science and later in biology and biomedical research. In terms of the latter, the National Center for X-ray Tomography (NCXT) is one of the principal developers of this technology, in particular for imaging whole, hydrated cells. 22