Brian D. Ross, PhD, Ann Arbor, MI (Abstract Co Chest Radiology. Mettler, Fred A. ••Essentials of radiology / Fred A. Mettler, Jr.—2nd ed. Writing a basic. Chest X-ray = 3 days of background radiation .. Chest Radiology: The Essentials. ronaldweinland.info ronaldweinland.info RADIOLOGY - Clinical Radiology - The Essentials 4E () [PDF] Agents 43 3 Interventional Radiology 49 4 Chest Imaging 79 5 Cardiac Imaging 6.
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Chest Radiology: The Essentials. Grading Key = outstanding; = good; = fair; ***** *** Book Reviews **** = excellent; * = poor. scientific, and managerial ideals in. This book is based on Dr Collins's award-winning syllabus for a hour chest radiology course presented through the University of Wisconsin. This book is based on Dr Collins's award-winning syllabus for a hour chest radiology course pre- sented through the University of Wis- consin radiology.
The stories of doctors reflect the frustrations, sorrows, and joys experienced in practice and teaching; the problems of balancing family and career; and the valuable insights and energies to be found in relationships with patients. The stories of patients reveal a broad spectrum of patients' attitudes, feelings, needs, perceptions, and sensitivities that relate to pain, fear, loss, isolation, and the need for acknowledgment, recognition, and better communication. Strengths: The book's exceptional value is derived from good writing: the use of narrative to reveal important elements of experiential, ethical, and relational aspects of medical practice that cannot be expressed in logical, analytical discourse and philosophical grammar. Excellence is evident in "the sheer force of good writing.. Recommended Readership: The book has universal appeal for any caregiver or patient who has ever felt the tension between humanistic, scientific, and managerial ideals. Many physicians who have read the pieces in the Annals are likely to enjoy them again in this compact collection. Sherris and Eugene B.
I decided my eyes were not completely dark adapted. I walked across the parking lot to his office to do an upper gastrointestinal series. After the patient drank some more barium. An electron volt is the amount of energy an electron gains as it is accelerated through a potential of 1V. X-rays in the diagnostic range shaded area are near the end of the spectrum of short wavelengths.
For the purpose of this discussion. The Essentials Table 1. In general. This is measured in electron volts. Production of Images Image production by x-rays results from attenuation of those x-rays by the material through which they pass. Moving these electrons toward the anode at an energy level sufficient to produce x-rays requires a high potential—up to An atom is ionized when it loses an electron. Production of X-Rays X-rays used in diagnostic radiology require a vacuum and the presence of a high potential difference between a cathode and an anode.
The spectrum of electromagnetic radiation is illustrated in Figure 1. In the basic x-ray tube. X-rays follow the same physical laws as light. Any photon with approximately 15 or more electron volts of energy is capable of producing ionization in atoms and molecules ionizing radiation.
The amount of energy carried by each photon depends on the wavelength of the radiation. Absorption is also influenced by the atomic number of the structure. X-rays are described in terms of particles or packets of energy called quanta or photons. Attenuation is the process by which x-rays are removed from a beam through absorption and scatter. The shorter the wavelength of an electromagnetic radiation form.
The denser. When the accelerated electrons strike the tungsten anode. Structures that produce more blackening on film are referred to as being radiolucent. Physical density is the type of density just described.
The shorter the wavelength. CT has the ability to detect minute differences in the densities of tissues and portray them in varying shades of gray. There are four types of radiographic densities.
These CT densities are measured in Hounsfield units. Distilled water at a standard pressure is 5 Figure 1. Radiographic density refers to the degree of blackness of a film. The radiographic density of a substance is related to its physical density. Contrast material containing either barium or iodine molecules. The numbers represent the wavelength of the particular radiation. The effect on film or other recording media occurs paradoxically: Radiographic contrast is the difference in radiographic densities on a film.
Radiographic Density It is important to differentiate between two types of densities that you will hear mentioned when discussing radiographs with radiologists or other colleagues: Greater absorption produces less darkening on the final image.
The Essentials Figure 1. Denser tissue absorbs more x-rays.
The denser a particular material. The amount of blackening on the film depends entirely on the amount of radiation reaching it and therefore on the amount attenuated or removed from the beam by the subject. This emulsion is sensitive to light and radiation. The brightness of the light is proportional to the intensity of the x-ray beam striking the plate and depends on the amount of radiation removed from the beam by the object being irradiated. X-ray film consists of a plastic sheet coated with a thin emulsion that contains silver bromide and a small amount of silver iodide.
When the film is exposed to light or to ionizing radiation and then developed. Bone densities are very high. Other recording media include fluoroscopic screen and image intensification systems. A protective coating covers the emulsion.
The technology of image intensification was originally developed around for military use at night. These crystals respond. Photodetectors Photons emitted by radioisotopes are detected with sodium iodide crystals. X-ray film is still used in many parts of the world. Intensifying screens. Fluoroscopic Screen A fluoroscopic screen is coated with a substance phosphor that gives off visible light or fluoresces when it is irradiated. This system allows the radiologist to see the image clearly without requiring dark adaptation of the eyes.
Acquisition DR. Figure 1. CT and MR scanners and digital radiography units use electronic sensors that actually measure the attenuation coefficient of tissue through which the x-ray beam has passed and converts this mathematical value into a digitized shade of gray.
Clinicians can view images by accessing them directly from the central archive to their work areas. Images that are too dark or too light can be electronically manipulated at the reading station Fig. The problem of delay in transportation of x-ray films from the processing area to the file room and then to the reading areas is eliminated because the images are sent directly from the processing area to the reading areas electronically.
The data are fed into a computer that plots the location of each of those measurements to produce the computer image. This is recorded on compact discs CDs or digital video discs DVDs and is displayed on a television monitor. The radiation intensity at each site is recorded digitally to produce a digital image that can be transmitted directly to a highresolution monitor. It forms the basis for the picture archiving and communications system PACS.
Modern radiology departments no longer have conventional view boxes. The typical PACS uses a photosensitive electronic plate that records the amount of radiation striking each location. The HIS provides all the medical information that a treating or consulting physician may need when seeing a patient.
In fully integrated systems. The far right screen shows the consultation report. Teleradiology Teleradiology is a natural offshoot of electronic imaging. Other manipulations allow changes in density and contrast as well as reversal of densities. A B Figure 1. The two center screens are high-resolution monitors for viewing the images and comparing studies. Only one screen is used for viewing. Among its many applications. Diagnostic console in the radiology department.
Modern teleradiology systems are Web based. It is also an important resource for the radiologist. The RIS is used for scheduling examinations. Frontal radiograph of patient with known renal carcinoma shows suspected nodules in both upper lobes arrows.
Satellite console in an office. State-of-the-art computerized imaging technology requires cooperation among members of the radiology department as well as those of the medical records department and hospital administration.
Several enterprising companies have located in Sydney. Same image with bones electronically subtracted shows bilateral lung nodules arrows. Scatter Scatter is produced by deflection of some of the primary radiation beam. To prevent the lead strips from casting their own shadows as they absorb radiation.
Image Quality Physical and geometric factors affect the radiographic image. In this situation. The third use of teleradiology is for consultation. To eliminate as much scatter as possible. Magnification The radiographic image is a two-dimensional representation of three-dimensional structures. Voice recognition technology has further improved the turnaround time to produce a final report on imaging studies.
These factors include thickness of the part being studied. This system is known as the Bucky-Potter system. In the past this was done by using an intensifying screen—a device coated with a fluorescent material that gives off visible light when struck by x-rays. In our department. Motion Motion of the part being radiographed results in a blurred.
The Essentials As a rule. Modern digital imaging has replaced intensifying screens. The visible light rather than the x-rays themselves produces the exposure. When voice recognition is combined with PACS technology. The farther an object is from the cassette. Motion may be overcome by shortening the exposure time. The second application of teleradiology is providing coverage for facilities that do not have on-site radiologists.
This may involve some night and weekend work as well. Voice recognition programs produce quality reports with little need for editing by the radiologist. A grid absorbs scattered radiation. The radiographic image of an object depends on the sum of the shadows X-ray source Figure 1. The object is closer to the cassette. The object is farther from the cassette. This has considerable importance in evaluating the heart on chest radiographs.
Distortion Distortion occurs when the object being radiographed is not perfectly perpendicular to the x-ray beam. Angling of the lead strips permits only the primary x-ray beam to pass through. On the standard chest radiograph. This will produce the truest image of the region of interest. Because the heart is located anteriorly.
Scatter radiation Recording medium digital plate or film the magnification and the lesser the sharpness. The best rule to follow to reduce the undesirable effect of magnification is to have the part of greatest interest closest to the cassette. Lordotic view of the same patient made with the patient bending backward toward the film shows a dramatic change in the appearance of the heart.
In performing radiographic examinations. For diagnostic clarity. Changes in the relationship of that object to the x-ray beam may distort its radiographic image Fig. Examples of radiographic studies with which you are familiar include chest. Posteriorto-anterior PA radiograph of the chest in a patient with right middle lobe pneumonia. The Essentials produced by that object when x-rayed.
The obsolete term plain film refers to radiographs in which no contrast material is used to enhance various body structures. Angling the x-ray beam while the objects remain in the same relationship to one another results in an overlapping image that is not a true representation of the actual objects. The shape of an object on a radiograph depends on the angle at which the radiographic beam strikes it. Despite being a fast and inexpensive way to determine the presence or absence of lung nodules.
Two objects of similar size cast distinct images when the x-ray beam is nearly perpendicular. The difference in size is the result of magnification. Fluoroscopic spot film shows the density in question to be the result of bone spurs bridging the thoracic vertebral bodies.
There was no tumor. Contrast Examinations Radiography is adequate for situations in which natural radiographic contrast exists between body structures. Contrast examinations were used more extensively in the past to evaluate abdominal or intracranial masses.
To examine structures that do not have inherent contrast differences from the surrounding tissues. Lateral view shows the mass to be posterior arrow. In addition to barium preparations. They may be administered either by mouth antegrade or by rectum retrograde alone or. Three areas deserve specific mention: Double-contrast examination shows a tumor along the greater curvature arrows. Gastrointestinal Tract The most common contrast material used for gastrointestinal examinations is a preparation of barium sulfate mixed with other agents to produce a uniform suspension.
Single-contrast barium enema shows a polyp in the descending colon arrow in a patient with ulcerative colitis.
Note the loss of haustral markings. Gas-enhanced studies are referred to as air contrast studies Fig. Single-contrast examination of the stomach demonstrates a large gastric ulcer arrows. An air contrast barium enema in the same patient. Water-soluble agents. A sinogram or fistulogram involves the injection of contrast material through an abnormal sinus tract into the body. Urinary Tract Urography is the radiographic study of the urinary tract. Water-soluble agents are commonly used for these studies.
Vascular System Angiography is the study of the vascular system. In evaluating an empyema cavity in the chest. They also cost more and thus are not used on a routine basis. Although barium is a chemically inert substance. The physiology of these agents is discussed in Chapter 2. The contrast agents used for this study are primarily the ionic water-soluble salts of diatrizoic or iothalamic acids or the nonionic agents iopamidol or iohexol.
In these studies. This is a subtraction image in which black and white are reversed to improve contrast. These are administered intravenously intravenous urogram or retrograde to study the urethra. Note the irregularity and ballooning of the aortic arch at the site of injury arrows. Water-soluble agents similar to those used for urography are injected either intra-arterially or intravenously.
Intravenous urography largely has been replaced by CT. Myelogram shows compression of the subarachnoid space by the herniated disc material arrows.
Computed Tomography Under ordinary circumstances. Note the compression of the thecal sac by the herniated material. The development of MR imaging.
The main indication is evidence of spinal cord or nerve root compression. Cerebrospinal fluid is also removed for study at this time. The most common lesion is a herniated nucleus pulposus from a lumbar disc. It may also be performed by puncture of the cisterna magna when there is a complete block within the vertebral canal and it is necessary to inject contrast medium above the lesion.
Myelography is performed by inserting a needle between the spinous processes of lumbar vertebrae and entering the subarachnoid space. Today myelography is combined with computed tomography. Godfrey Hounsfield was the first to develop the CT scanner in England. Myelography is often performed in conjunction with CT. This is the basis of CT. Diseases encroaching on the vertebral canal may be studied by myelography. For his efforts. The data from these measurements are analyzed by a computer system that assigns different shades of gray CT or Hounsfield numbers to different structures based on their absorption or attenuation coefficients.
In spiral CT. In earlier CT studies. Modern CT scanners use arrays of detectors to shorten the time needed for the scan. This speed is important when breath holding is necessary to prevent motion artifacts.
The narrower sections allow greater detail to be shown of the bones. It is now possible to image an entire thorax or an entire abdomen in 20 seconds or less. For example. Imaging Modern CT is performed using helical or spiral technology. The computer reconstructs a picture based on geometric plots of where these measurements were taken. In CT Fig. Detectors measure the amount of radiation removed from the x-ray beam. The technology results in images that are obtained rapidly that.
In the modern CT scanner. This allows the detector system to measure the intensity of radiation passing through the subject. Speed is particularly essential when trauma victims are imaged. Rapid throughput of patients is made possible. It is possible to reconstruct a study of the thoracic and lumbar spine from the same data set at narrower 2 mm slice thickness. In addition to the rapidity.
Horizontal arrows indicate the direction of patient travel through the gantry. The use of isotopes for laboratory purposes and for evaluating physiologic functions is not discussed in this book. Spiral CT produces a continuous band of information.
Other uses include studies of patients with abdominal trauma Fig. Note how well the tumor is defined against the normal brain tissue. The diagnostic radiologist is concerned with the imaging aspect of the field. The Essentials B Figure 1. The contrast agents used are identical to those used in angiography or urography.
Once the information has been recorded. Methods of acquisition of the data. The data from the study are linked to the PACS or teleradiology system. In spiral CT bottom. Scanning the rest of the body is particularly useful in evaluating visceral neoplasms Fig. In conventional CT top. This study is particularly useful in defining and localizing brain tumors primary or metastatic and in evaluating patients with neurologic emergencies such as intracerebral hemorrhage and subdural hematoma.
Diagnostic Uses Cranial scanning is performed to evaluate patients with various neurologic findings. To enhance the appearance of certain viscera or vascular neoplasms. All state-of-the-art CT scanners use spiral and multidetector technology. Conventional CT obtains individual slices. Note the compression of normal brain tissue by the hematoma. Nuclear Imaging Nuclear medicine traditionally has two divisions: Note the severe comminution and depression anteriorly arrow.
These compounds may be labeled with a radioactive substance of sufficient energy level to allow detection outside the body. Frontal radiograph shows a comminuted fracture through the medial and lateral plateaus arrows. The ideal isotope can be administered in low doses. Lateral radiograph shows the comminution arrow. This view mirrors what the surgeon will encounter. In medicine there are three types of half-lives: Half-Life The half-life of an element is the time necessary for its degradation to one-half of its original activity.
The physical half-life is the period in which the element would decay on its own. Three-dimensional reconstruction shows the severe comminution. D E Radioactive Isotope Uptake Nuclear imaging depends on the selective uptake of different compounds by different organs of the body. This occurs naturally. Coronal C and sagittal D reconstructed tomographic images show the extent of the fractures to better advantage.
Technetium 99 m fulfills most of these requirements. Note the differences in the appearance in images made from the same data set.
The patient also had leg paresthesias and a spine study was reconstructed from the same data set at 2 mm slice intervals. Axial reconstructed images at bone and soft tissue windows. An abdominal scan was performed at 5 mm slice intervals for suspected prostatitis. B and C. Sagittal reconstructed image from original study shows poor detail.
Detail view of axial CT abdominal image shows degenerative changes in the lower lumbar spine arrow. Sagittal reconstructed image using the narrow slice thickness shows multiple disc—osteophyte complexes arrows in much better detail. A breast prosthesis P is evident.
Note the bowing of the septum arrow. Biologic half-life concerns the normal physiologic removal of the substance to which the isotope has been attached. Although the physical half-life of technetium 99m is approximately 6 hours. Static or Dynamic Imaging Nuclear imaging is performed on either a static or dynamic basis.
The effective half-life is a mathematical derivation based on a formula combining the biologic and physical half-lives. Static studies include the thyroid. Common types of scans are It measures the actual time the isotope remains effective within the body. Cranial CT shows a mass M in the right occipital region.
Compare with part figure A. Dynamic studies additionally include rapid sequence images to assess blood flow to organs such as the skeleton and the kidneys. The same section at soft tissue windows. The dense areas in the laceration are hemorrhage.
Left renal fracture showing a large retroperitoneal hematoma asterisk and active bleeding arrows. Note the difference in kidney contour and texture compared with the left. Note the compression of the right side of the brain by the low-density hematoma arrows. Axial CT image shows a large laceration asterisk in the middle of the liver. Compare with the left. There is loss of the sulci on the left as the result of compression. Axial CT image through the pelvis shows a large abscess anteriorly asterisk containing gas.
In the parameters used for medical imaging. With newer technology. B listed in Table 1. The initial application of PET scanning was primarily to evaluate brain metabolism by assessing blood flow to a specific part of the brain—for example.
Cell sequestration e. There are basically five mechanisms of isotope concentration within the body: PET scanning is more frequently used for oncologic imaging in diagnosis.
MR imaging is based on the principles described by Felix Bloch and Edward Purcell in an experimental procedure they designed to evaluate the chemical characteristics of matter on a molecular level. Areas of increased brain activity show selective uptake of the injected isotope. Bloch and Purcell were awarded the Nobel Prize in physics in Note the subphrenic collection of fluid and gas arrow.
Phagocytosis e. Positron emission tomography PET uses cyclotron.. Blood pool or compartmental localization e. Magnetic Resonance Imaging MR imaging is a noninvasive technique that does not use ionizing radiation.
The reason for this is the ability of the PET scan to show increased use of glucose by the tumor Fig. Coronal reconstructed image shows the abscess tracking cephalad along the right abdominal gutter asterisk..
For their work. Capillary blockage e. It has been particularly useful in evaluating patients with senile dementia or Alzheimer disease Fig. Physiologic incorporation e. The Essentials B A Figure 1. Axial A and sagittal B reconstructed images show a lucent lesion in the medial proximal femur with a dense nidus arrows.
C Table 1. Axial image shows a probe arrow inserted into the tumor for percutaneous ablation. Note the large photopenic areas.
Raymond Damadian began investigating the possibilities of using MR for imaging in The development of computer imaging algorithms for CT accelerated the development of MR for medical diagnosis.
Paul Lauterbur and Peter Mansfield were able to produce the first successful images using this technique. The nuclei of any atoms with odd numbers of nucleons protons and neutrons behave like weak magnets in that they align themselves with a strong magnetic field. The ventilation scan is normal. Magnetic Resonance Technology MR imaging uses a pulsed radiofrequency RF beam in the presence of a high magnetic field to produce high-quality images of the body in any plane. This combination of findings is diagnostic of pulmonary embolism.
Perfusion scan of the lungs shows many areas devoid of radioisotope photopenia bilaterally. Note the areas of the increased tracer concentration blackness throughout the skeleton.
This signal can then be amplified and recorded—the basis for MR imaging.
Although many nuclei may be used for MR imaging. Fourth row: MR imaging has the advantage of being able to highlight the different pathologic changes in different tissues through contrast manipulation. Signal intensity depends on several factors. Second row: MR imaging displays structures in a transverse or axial fashion. Fifth row: Sixth row: This is accomplished by altering the pattern of RF pulses in a study. Distribution of blood flow is uniform over the left ventricle. Third row: The common display parameters used are the sagittal.
Tissues that contain very little hydrogen. The greater the hydrogen density. The MR image reflects the strength or intensity of the magnetic resonance RF signal received from the sample. MR imaging can also produce images in any other planes. Tissues high in hydrogen. T1 and T2. First row: Symmetric cortical perfusion in a normal patient. A B Alphabet Soup: Other terms that you will encounter when discussing MR examinations with a radiologist or when reviewing the literature are: Tesla T: The unit of measure of magnetic flux density.
Echo time: The time between the middle of the RF pulse and the middle of spin echo production. Repeat fused study 3 months later shows enlargement of both lesions. Commonly used imaging parameters: Spin echo.
Note the exact superimposition of the abnormality on the combined study. T2 is the rate at which the RF signal emitted by the nuclei decreases after RF perturbation. Repetition time: The time between the beginning of one pulse sequence and the beginning of succeeding pulse sequences. Coronal PET image shows both lesions arrows. CT image shows a left adrenal mass arrow and an area of low density in the right lobe of the liver asterisk.
MRA is also commonly used for vascular abnormalities Fig. Ultrasound is a nonionizing form of. This will accommodate knees. A pulsed radiofrequency RF beam deflects the molecules as they absorb the energy from that beam.
A third type of magnet. When the RF beam is switched off. This is well above the normal human ear response of 20 to Diagnostic Ultrasound Diagnostic ultrasound is a noninvasive imaging technique that uses sonic energy in the frequency range of 1 to 10 MHz 1. Diagnostic Uses MR imaging is used primarily for studying intracranial Fig.
Machines with magnet strength of 0. Image quality varies with these units. This may be measured with a detector D. Following magnetization. Numerous smaller strength magnets are also on the market. The molecules in the body behave like small bar magnets and are arranged in a random fashion.
The molecules align themselves along the plane of magnetization. Resting state. Magnet Strength Typical high-field MR imaging units have a magnet strength of 1. Most ultrasound machines are portable. The transducer then acts as a receiver. Real-time ultrasound allows dynamic scanning of moving objects such as a fetus This is the same patient as in Fig. A continuous stream of ultrasound waves are emitted from the transducer and reflected from the tissues being imaged.
Ultrasound waves are greatly reflected by the interface between soft tissue and air or bone. Note the internal structure of the tumor compared with Figure 1. Axial image shows the tumor M to much better advantage. Echoes or reflections of the ultrasound beam from interfaces between tissues with various acoustic properties yield information on the size.
An additional feature of modern ultrasound is Doppler evaluation of blood vessels. This technique also permits rapid and efficient screening of a body region Fig. In the past decade. Sagittal T2weighted image shows the herniation at C4-C5 arrow. The technique is most commonly done in the. C in utero Fig. With this technique. Axial T2-weighted image shows the large fragment on the right arrow. Observing moving body parts. Note the compression of spinal cord. Ultrasound is an interactive modality.
Note the prevertebral asterisk hematoma and posterior hemorrhage H. Extension fracture dislocation at C4-C5. Coronal magnetic resonance image shows flipped fragment of medial meniscus arrow near the center of the joint.
The spinal cord is transected posterior to C3 arrow. Note the absence of a normal triangular meniscal image posteriorly. Cord edema black arrow in a patient with an extension injury at C5-C6. Sagittal image shows the torn anterior horn of the meniscus arrow.
Note the ruptured anterior and posterior longitudinal ligaments white arrows and the posterior soft tissue hemorrhage asterisk. A Figure 1. The duodenum D and gallbladder G are also marked. Some contrast fills the gallbladder G. Other images showed the tumor to encroach on the subarachnoid space. Ultrasound is unable to cross a tissue—gas or tissue—bone boundary. Motion-mode M-mode ultrasound is used in echocardiography to study the dynamic changes of cardiac structures.
Sagittal T1-weighted image shows areas of low signal dark as well as compression in two vertebrae. Drawbacks of Ultrasound There are disadvantages to ultrasound. The Essentials A Figure 1. B Figure 1. Ultrasoundguided fluid aspirations. Ultrasound is also a useful tool in performing interventional procedures. Doppler evaluation of venous structures can be performed to rule out occlusion from deep venous thrombosis.
The cardiac structures. Axial T2-weighted image shows the obstructing stone arrow. In Three Approaches to Studies This chapter has outlined the many studies available to solve various clinical problems. The It is also not surprising that the cost of the equipment to perform those imaging studies has also increased dramatically. The following arteries are demonstrated: In the s. By Since the s. Note the excellent demonstration of the normal vascular anatomy.
Note the placenta P. Ultrasound has become a primary diagnostic tool in obstetrics. The liver L lies immediately above the gallbladder.
Shotgun Approach The shotgun approach is one that is used too frequently. Three approaches are currently in use: Although this approach requires some thought on the part of the clinician and study selectivity is possible. Ultrasound examination in the longitudinal plane shows a gallstone measuring 0. It takes little thought to order a battery of diagnostic laboratory and imaging studies for each patient in the hope that one or more of those tests will provide important diagnostic information.
Courtesy of Mihra Taljanovic. In this instance. The arrows point to the neck of the cyst. The greater the velocity range. The vessel walls are smooth without visible atheromatous plaques. Significant stenosis in a right internal carotid artery RICA. The Doppler waveform also allows for evaluation of the degree of laminar flow disruption. This is reflected by the range of red blood cell velocities. The rectangle within the vessel lumen small arrow is the Doppler sample site from which the flow characteristics and velocities generate the Doppler waveform tracing shown to the right of the gray-scale image.
Longitudinal image shows the cyst above the medial head of the gastrocnemius MHG. Normal left common carotid artery LCCA. Transverse ultrasound image shows the cyst as a sonolucent area above the denser band of the semimembranosus tendon SMT. The gray-scale image of a portion of an RICA shows gross vessel wall irregularity with significant stenosis near the Doppler sample site small arrow. Compare these tracings and images with A. The gray-scale image of a portion of the LCCA shows the vessel to be widely patent.
Medicolegal Concerns and Costs I have raised two issues in the preceding paragraph: MR Rx. The clinical. Feeding this is a tort Figure 1. Directed Approach The directed approach is a carefully thought-out process in which the clinician has performed a thorough history and physical examination and then considers the diagnostic possibilities in that patient.
The clinician chooses diagnostic studies based on probability of diagnostic yield. Many patients expect perfect results and. I prefer this approach and stress it daily to my consulting clinicians as well as to students and residents in all disciplines.
Imaging studies are highlighted. Low back pain Acute History and physical Conservative Rx heat.
In recent years. CT takes less than half the time needed to do a complete radiographic examination. Of course. In addition to being much more sensitive at detecting fractures. Issues that involve radiology in malpractice cases involve several areas: When you order diagnostic imaging. The radiologist should immediately communicate any urgent findings back to you and should document the fact that such information was given.
When considering performing a study. Each panel was charged with the task of developing a series of clinical conditions and variations that could serve as the basis for determining the appropriateness of imaging studies. For each clinical condition. The results were first published by the ACR in Put another way. Screening Examinations One final issue to be discussed is that of so-called screening examinations. As a result. Although it is helpful to consider costs in those terms.
Numerous studies have validated the fact that CT is more cost-effective than radiography for patients with suspected spine injury. I was an expert witness for the defense in a case involving delayed diagnosis of a fractured hip. Cost-Effectiveness When we mention the cost of a study we usually think of how much patients are billed for that service. CT of the cervical spine has replaced radiography for screening patients suspected of having cervical injury.
The full document may be viewed online and downloaded from the ACR web site at http: The task force consisted of 10 panels of expert radiologists and clinical consultants in each of the 10 subspecialties of diagnostic radiology.
Entrepreneurs have flooded the airwaves. The recommendations. Not only should you communicate with the radiologist. Not surprisingly. As a clinician. There is no credible evidence that whole-body CT or MR screening of the general population is effective at identifying early malignancies or other abnormalities. Colonoscopy or barium enema is also effective in finding polyps.
As the practice of radiology has become more organ—system oriented in larger hospitals. The generic answer is no. Three areas have demonstrated their ability to diagnose malignancies in early stages: Screening mammography is effective in identifying small cancers. There is little benefit in ordering expensive studies that will duplicate the diagnostic information. These radiologists work closely with specific groups of clinicians to solve their special diagnostic problems.
Rating Scale: The radiologist may be better able to tailor an examination to the exact needs of the patient. Radiologic Procedure Rating X-ray. Radiologists have been extensively trained in each of the imaging modalities. They make themselves available to consult on request with the clinician. Radiologic subspecialists are often on call to perform studies after normal working hours.
Keep in mind. American College of Radiology. They often participate in multidisciplinary conferences. Many studies provide similar information. Appropriateness Criteria for Imaging and Treatment Decisions. This means that requests for diagnostic studies should contain pertinent clinical information.
These documents specify indications for studies. You should learn to make use of this most valuable resource. Reprinted with permission. This will result in time saved in both the studies obtained and the hospital stay.
The clinicians. A secondary benefit will be cost containment—a topic of continuing importance. Variant 1: Chronic Neck Pain Patient without or with a history of previous trauma. Large radiology groups have members who are specialists in neuroimaging.
Crues JV. Diagnostic imaging is performed on nearly all patients seen in medical practice. A History of the Radiological Sciences: Essentials of Nuclear Medicine Imaging. Fishman EK. Excellence is evident in "the sheer force of good writing.. Recommended Readership: The book has universal appeal for any caregiver or patient who has ever felt the tension between humanistic, scientific, and managerial ideals. Many physicians who have read the pieces in the Annals are likely to enjoy them again in this compact collection.
Sherris and Eugene B. Scope ofBook: The book provides an introduction to basic surgical skills and principles. Contents: In the initial chapters, the authors describe the operating room environment and discuss wound healing, basic principles of surgery, local anesthetics, scrubbing, and surgical instruments. They then focus on surgical technique, including types of knots and suture methods, means for achieving hemostasis, and wound closures, from the most simple to complex skin flaps. Finally, they review the essentials of postoperative wound care.
Oriented toward medical students, the book includes a summary set of quiz questions and a glossary of terms. The accompanying CD-ROM demonstrates the various procedures and techniques with clear video depictions. Strengths: This is absolutely the best book I have ever seen to introduce physicians to the basic environment of the operating room and to describe essential surgical techniques required of anyone performing surgical procedures.
Deficiencies: The teaching format, by necessity, oversimplifies such technical issues as needle selection and suture types. The graphics in both the text and the CD-ROM are uniformly excellent, except for a number of poor-quality black-and-white photographs in the text.
Scope ofBook: The book is based on material from a popular 16hour course on the basics of chest radiology given annually at the University of Wisconsin. The emphasis is on the chest radiograph, but chest computed tomographic images are used liberally for correlation.
Contents: The text progresses from concepts of normal anatomy and signs in chest radiology to patterns of disease, including interstitial and alveolar lung disease, upper lung disease, peripheral lung disease, and pulmonary nodules. Atelectasis, airway disease, unilateral hyperlucent lung, mediastinal masses, and acute chest trauma all merit individual chapters. The chest wall, pleura, diaphragm, and neoplasms are also discussed. Topics that are not always included in books of this type include "tubes and lines," the immunocompromised patient, and congenital cardiac and lung disease.
A self-assessment quiz at the end of the book is a worthwhile bonus. Scope of Book: To the experiences of physicians published over many years in the Annals sections On Being a Doctor and Ad Libitum have been added insightful contributions from patients laypersons and doctors in the section On Being a Patient.
Contents: The most common central theme in this compilation is the need for and difficulty in effecting a balance of humanistic, Mayo Clin Proc. Mass reproduce only with permission from Mayo Clinic Proceedings. The clear, concise text provides background information sufficient for understanding the basics of chest radiology.
The self-assessment quiz offers a painless way to evaluate one's grasp of the material. Deficiencies: If you are a fan of mnemonics, you will love this book. To me, these are unnecessary, mindless learning devices. The discussion of what are termed pleural-based lesions could be improved. The occasional inconsistencies and errors of fact in the book are all of minor importance.
Recommended Readership: This book is appropriate for radiology residents at all levels of training, including those preparing for the oral board certification examinations.