American Journal of Roentgenology

OBJECTIVE. We sought to ascertain the actual effect of each of a broad range of factors that plausibly might affect starting salary.

MATERIALS AND METHODS. We surveyed radiologists who completed training in 1997 and obtained 487 relevant responses. Multiple regression analysis was used to identify the independent effects of characteristics of the physician, his or her job and employment search, and market area characteristics of his or her practice locality.

RESULTS. Academic starting salaries were, other things equal, 6% below private practice. Residency-only graduates had incomes 7% below a typical fellowship income. Only a few fellowship fields garnered incomes that were significantly different from the typical income. More managed care in a locality was associated with lower income, and a higher percentage of elderly in the locality was associated with a higher income. We found no statistically significant (p < 0.05) effects of sex, job location constraints, local per capita income, local cost of living, or (generally) graduate quality as measured by the ranking of a graduate's residency program.

CONCLUSION. The determinants of income are multiple and varied, including physician characteristics, such as field of subspecialty training; job characteristics, such as academic versus private practice employment; and market area characteristics. However, the study yielded as many puzzling, negative findings, such as the lack of effect of physician quality or of even severe locational constraints, as positive, expected findings.

OBJECTIVE. The purpose of our study was to model the supply and demand for diagnostic radiologists over the next 30 years under alternative scenarios.

MATERIALS AND METHODS. We used responses from the American College of Radiology's 2000 Survey of Diagnostic Radiologists and Radiation Oncologists to determine the current age distribution and activity of diagnostic radiologists. The numbers entering the profession were projected using three assumptions: no change in training programs, reduction of residency to 3 years (or otherwise increasing the annual number of graduates by one third), and elimination of most fellowship programs. Demand projections assume a 5% shortage in 2001 and depend on growth rates of the population, aging, scenarios of growth of age-standardized demand, and the effect of possibly productivity-enhancing technologies such as PACS (picture archiving and communication systems).

RESULTS. Only a one-third increase in annual graduates materially increases the work-force relative to current training patterns. In all cases, the growth rate of the demand for radiologists far outstrips the supply over a 30-year horizon. In the shorter term, projections of current trends point to an increasing shortage, but rapid major productivity increases could produce a surplus.

CONCLUSION. Those in the field of diagnostic radiology should consider measures to mitigate the increasing shortage, while monitoring developments that might signal departures from current trends in supply and demand.

OBJECTIVE. The purpose of our study was to describe patterns of airway compression identified on cross-sectional imaging in infants and children with either right aortic arch and aberrant left subclavian artery or left aortic arch with aberrant right subclavian artery.

MATERIALS AND METHODS. Data from MR imaging and CT performed to evaluate pediatric patients for extrinsic airway compression were reviewed for cases that revealed an aberrant right or left subclavian artery. Clinical, endoscopic, and imaging findings in identified cases were reviewed. Recurrent patterns of extrinsic compression were reviewed among cases.

RESULTS. Twelve patients with right aortic arch with aberrant left subclavian artery and nine patients with left aortic arch and aberrant right subclavian artery were identified. All 12 with right aortic arch with aberrant left subclavian artery had airway compression shown, with multiple sites or diffuse compression in six. Of these 12 patients, nine had compression at the level of the arch and aberrant subclavian artery (10 had Kommerell's diverticulum), and nine had compression of the distal airway in association with a midline descending aorta. Five of the nine patients with left aortic arch and aberrant right subclavian artery had airway compression shown, all at the level of the arch and aberrant subclavian artery. None of these compressions was associated with either Kommerell's diverticulum or midline descending aorta.

CONCLUSION. Both right and left aberrant subclavian arteries can be associated with symptomatic airway compression, but the patterns of compression are different. The airway compression in right aortic arch with aberrant left subclavian artery is often associated with either Kommerell's diverticulum or midline descending aorta, whereas compression associated with left aortic arch and aberrant right subclavian artery is not.

OBJECTIVE. MR imaging of the breast can depict cancer that is occult on mammography and at physical examination. Our study was undertaken to determine the ease of performance and the outcome of MR imaging—guided needle localization and surgical excision of breast lesions.

MATERIALS AND METHODS. Retrospective review revealed 101 consecutive breast lesions that had preoperative MR imaging—guided needle localization with commercially available equipment, including a 1.5-T magnet with a breast surface coil, a dedicated biopsy compression device, and MR imaging—compatible hookwires. Imaging studies and medical records were reviewed.

RESULTS. Histologic findings in these 101 lesions were carcinoma in 31 (30.7%), high-risk lesions (atypical ductal hyperplasia or lobular carcinoma in situ) in nine (8.9%), and benign lesions in 61 (60.4%). Fifteen (48.4%) of 31 carcinomas were ductal carcinoma in situ, and 16 (51.6%) were infiltrating carcinoma (size range, 0.1-2.0 cm; median, 1.2 cm). Carcinoma was found in 16 (45.7%) of 35 lesions detected in women with synchronous cancer, 10 (32.3%) of 31 lesions detected on MR imaging for problem solving, and five (14.3%) of 35 lesions detected on MR screening. The time range to perform MR imaging—guided localization was 15-59 min (median time, 31 min). Complications encountered in three cases were retained wire fragments in two and breakage of the wire tip in one.

CONCLUSION. MR imaging—guided needle localization can be performed quickly and safely with commercially available equipment. The positive predictive value of MR imaging—guided needle localization (30.7%) was comparable to that reported for mammographically guided needle localization and was highest in women with synchronous breast cancer.

OBJECTIVE. Our purpose was to compare the two different body positions for stereotactic large-core breast biopsy with regard to sensitivity, specificity, and accuracy, as well as complication rate.

SUBJECTS AND METHODS. Two hundred patients had large-core breast biopsy performed either in the prone (n = 100) or in the sitting (n = 100) position and subsequently underwent surgical resection. The histopathologic findings of large-core breast biopsy and surgery of all 200 patients were compared; sensitivity, specificity, and accuracy were calculated for both groups. Biopsy-associated complications were prospectively recorded for immediate and delayed events and for technical failures in both groups.

RESULTS. Sensitivity (96%), specificity (100%), and accuracy (98%) were the same for both groups with two false-negative findings in each group. The two false-negative results in the sitting group were caused by vasovagal reactions, whereas those in the prone group were caused by technical failure and uncomfortable biopsy position. More statistically significant complications (seven vs four, p < 0.001) and vasovagal reactions (seven vs two, p < 0.0001) were seen in the sitting group.

CONCLUSION. For performance of large-core breast biopsy, both the prone and sitting positions are reliable and accurate methods. However, vasovagal reactions that could potentially complicate biopsy were seen significantly more often in the sitting position.

OBJECTIVE. Our study aimed to correlate the dynamic contrast-enhanced MR appearance of infiltrating lobular carcinoma of the breast with histopathologic findings.

MATERIALS AND METHODS. We retrospectively reviewed the high-resolution, fat-suppressed and dynamic contrast-enhanced MR images of 13 of 20 women diagnosed with pathologically proven infiltrating lobular carcinoma of the breast. Twelve of the 13 women presented with breast symptoms and underwent mammography. Five of the women also had breast sonography. MR imaging was performed for evaluation of disease extent before the patients underwent modified radical mastectomy (n = 11) or lumpectomy (n = 2). Three experienced radiologists reviewed the MR scans. The tumor pattern types described on imaging were correlated with a detailed analysis of the pathology.

RESULTS. We found three patterns of infiltrating lobular carcinoma on MR imaging. The tumor pattern on imaging correlated with pathologic tumor morphology. We found the following patterns of infiltrating lobular carcinoma: a solitary mass with irregular margins (n = 4) that corresponded to the same appearance at pathology; multiple lesions, either connected by enhancing strands (n = 6) or separated by nonenhancing intervening tissue (n = 2), that correlated with the pathologic appearance of noncontiguous tumor foci, with malignant cells streaming in single-file fashion in the breast stroma or small tumor aggregates separated by normal tissue; and enhancing septa only, which were correlated with the histopathologic appearance of tumor cells streaming in the breast stroma (n = 1).

CONCLUSION. Infiltrating lobular carcinoma may be detected on MR imaging as solitary or multiple lesions that correspond to tumor morphology on pathologic examination. The appearance of multiple lesions or of enhancing fibroglandular breast elements on MR imaging is suggestive of infiltrating lobular carcinoma.

OBJECTIVE. The purpose of this study was to compare the efficacy of noninvasive multidetector CT (virtual bronchoscopic images, axial CT slices, coronal reformatted images, and sagittal reformatted images) in depicting and allowing accurate grading of tracheobronchial stenosis with that of flexible bronchoscopy.

MATERIALS AND METHODS. Multidetector CT and flexible bronchoscopy were used to examine 200 bronchial sections obtained from 20 patients (15 patients with bronchial carcinoma and five without central airways disease). Multidetector CT was performed using the following parameters: collimation, 4 × 2 mm, pitch, 1.375; and reconstruction intervals, 2 mm. Postprocessing was performed using surface rendering and multiplanar reformatted images. CT images were independently interpreted by two radiologists. The tracheobronchial stenoses revealed on flexible bronchoscopy were graded by a pulmonologist.

RESULTS. Virtual bronchoscopic findings, axial CT scans, and multiplanar reformatted images were highly accurate (98% accuracy for virtual bronchoscopic images, 96% for axial slices and coronal reformatted images, and 96.5% for sagittal reformatted images) in revealing tracheobronchial stenosis. In allowing accurate grading of tracheobronchial stenosis, images from virtual bronchoscopy correlated closely (r = 0.91) with those of flexible bronchoscopy. Because use of virtual bronchoscopic images reduced the overestimation of stenosis, these images allowed better assessment of stenosis than did axial CT slices (r = 0.84) or multiplanar reformatted images (r = 0.84) alone.

CONCLUSION. Multidetector CT virtual bronchoscopy is a reliable noninvasive method that allows accurate grading of tracheobronchial stenosis. However, it should be combined with the interpretation of axial CT images and multiplanar reformatted images for evaluation of surrounding structures and optimal spatial orientation.

OBJECTIVE. We evaluated the relationship of air trapping to mosaic perfusion in patients with pulmonary embolism.

SUBJECTS AND METHODS. Forty-one consecutive patients with suspected pulmonary embolism underwent expiratory CT followed by helical CT angiography. After excluding 12 patients who had airway disease or were smokers, we divided the patients into two groups: those with (n = 15) and without (n = 14) pulmonary embolism. For each patient, six expiratory images were evaluated for the presence of air trapping, and the corresponding six images from CT angiography were evaluated for the presence of mosaic perfusion. Clot locations were assessed on CT angiography and were correlated with the presence of air trapping and mosaic perfusion.

RESULTS. In patients with pulmonary embolism, mosaic perfusion was identified in 32 areas (seven patients, 46.7%), and air trapping was identified 68 areas (nine patients, 60%). Of the 32 areas of mosaic perfusion, 23 areas (71.9%) showed air trapping on expiratory CT scans. Of the 68 areas with air trapping on expiratory scans, 23 areas (33.8%) showed mosaic perfusion on inspiratory scans, and 44 areas (64.7%) had clots in the arteries leading to them. Clots were more frequently identified in areas of lower attenuation on inspiratory CT scans and air trapping (21/23) than in those of normal attenuation on inspiratory CT scans and air trapping (23/45) (p < 0.005). Only one patient without pulmonary embolism had air trapping (p < 0.005).

CONCLUSION. Air trapping is common in pulmonary embolism and may be the cause of mosaic perfusion. Air trapping can be seen distal to vessels not showing pulmonary embolism.

OBJECTIVE. In the Early Lung Cancer Action Project (ELCAP), we found not only solid but also part-solid and nonsolid nodules in patients at both baseline and repeat CT screening for lung cancer. We report the frequency and significance of part-solid and nonsolid nodules in comparison with solid nodules.

MATERIALS AND METHODS. We reviewed all instances of a positive finding in patients at baseline (from one to six noncalcified nodules) and annual repeat screenings (from one to six newly detected noncalcified nodules with interim growth) to classify each of the nodules as solid, part-solid, or nonsolid. We defined a solid nodule as a nodule that completely obscures the entire lung parenchyma within it. Part-solid nodules are those having sections that are solid in this sense, and nonsolid nodules are those with no solid parts. Chi-square statistics were used to test for differences in the malignancy rates.

RESULTS. Among the 233 instances of positive results at baseline screening, 44 (19%) involved a part-solid or nonsolid largest nodule (16 part-solid and 28 nonsolid). Among these 44 cases of positive findings, malignancy was diagnosed in 15 (34%) as opposed to a 7% malignancy rate for solid nodules (p = 0.000001). The malignancy rate for part-solid nodules was 63% (10/16), and the rate for nonsolid nodules was 18% (5/28). Even after standardizing for nodule size, the malignancy rate was significantly higher for part-solid nodules than for either solid ones (p = 0.004) or nonsolid ones (p = 0.03). The malignancy type in the part-solid or nonsolid nodules was predominantly bronchioloalveolar carcinoma or adenocarcinoma with bronchioloalveolar features, contrasting with other subtypes of adenocarcinoma found in the solid nodules (p = 0.0001). At annual repeat screenings, only 30 instances of positive test results have been obtained; seven of these involved part-solid or nonsolid nodules.

CONCLUSION. In CT screening for lung cancer, the detected nodule commonly is either only part-solid or nonsolid, but such a nodule is more likely to be malignant than a solid one, even when nodule size is taken into account.

OBJECTIVE. In patients who have a history of abdominopelvic radiation, surgery, or both, conventional colonoscopy may fail to examine the entire colon. The purpose of this study is to assess whether high-quality virtual colonoscopy can be achieved in this patient population.

MATERIALS AND METHODS. After colonic cleansing, 61 patients (16 men and 45 women; mean age, 64 years; age range, 27-81 years) underwent 63 virtual colonoscopy examinations after using either single- or multidetector CT (slice thickness, 3.75-5.0 mm; table speed, 1.7-11.25 cm/sec; pitch, 1.5-3.0; and overlapped reconstructions, 1.95-2.5 cm) in supine and prone positions after IV administration of 1 mg of glucagon and rectal air insufflation. Conventional two-dimensional axial images were analyzed on a PACS (picture archiving and communication system) workstation. Two radiologists, who were unaware of patient history, independently evaluated the colonic distention on a 4-point scale (4 = optimal distention) and fluid retention on a 3-point scale (3 = no fluid) for all segments of the colon in patients who were imaged in both the supine and prone positions. Segmental and total average colon scores were calculated.

RESULTS. Forty-one patients (65%; 43 examinations, 67%) underwent prior surgery, radiation, or both (surgery, n = 29; radiation, n = 3; both, n = 11). The average overall colonic distention and fluid retention for this group was 3.13 and 2.38, respectively, versus 3.24 and 2.3 in the control group (p = not significant).

CONCLUSION. High-quality examinations were achieved in patients who had previously undergone radiation, surgery, or both with no clinically significant difference in distention or fluid retention compared with the controls.

OBJECTIVE. The purpose of this study was to describe helical CT findings of gastric mucosa-associated lymphoid tissue (MALT) lymphoma and to correlate them with pathologic findings.

MATERIALS AND METHODS. We retrospectively reviewed CT examinations of 58 patients with confirmed gastric MALT lymphomas. Using the histopathologic grade of the MALT lymphomas, we divided the patients into two groups: those with high-grade lymphoma (n = 21) and those with low-grade lymphoma (n = 37). Common CT findings for the two groups were reviewed and compared.

RESULTS. Forty (69%) of the 58 patients showed at least one abnormality of the stomach on CT. Abnormalities included diffuse or segmental gastric wall thickening (66%, 38/58), lymphadenopathy (40%, 23/58), ulcer (22%, 13/58), and gastric mass (3%, 2/58). Eighteen (31%) of 58 patients were found to have no abnormality. The high-grade group had a higher incidence of abnormalities seen on CT than the low-grade group (100% vs 51%, respectively). Gastric wall thickening in the high-grade group was more diffuse (48% vs 8%) and severe (71% vs 14%; severe or moderate) than that seen in the low-grade group. Lymphadenopathy was visualized in 67% of the high-grade group and in 24% of the low-grade group. Gastric ulcer was found in 57% of the high-grade group and in only 5% of the low-grade group. The gastric mass formation was seen in only two patients in the high-grade group.

CONCLUSION. The CT findings of gastric MALT lymphoma that the two groups had in common were gastric wall thickening and lymphadenopathy. Although our results pointed to no specific CT finding for differentiating high-grade from low-grade gastric MALT lymphomas, we found that the absence of abnormality on CT is highly predictive of low-grade MALT lymphoma.

OBJECTIVE. We performed this study to evaluate the clinical relevance of renal excretion of ingested Gastrografin (methylglucamine diatrizoate) revealed on CT in the early treatment of patients who have undergone gastric surgery.

SUBJECTS AND METHODS. Unenhanced abdominal CT was performed before and then 1 hr to 1 hr 30 min after Gastrografin ingestion in 30 patients 7 days after gastric surgery and in 19 healthy adults who served as the control group. CT scans were reviewed for the opacification of the renal collecting system or urinary bladder after Gastrografin ingestion, a finding that represents renal excretion of the ingested contrast medium.

RESULTS. In the control group, four (21 %) of the 19 healthy adults showed renal excretion of ingested Gastrografin visualized as opacification of the urinary tract on CT scans obtained 1 hr to 1 hr 30 min after ingestion of the substance. Renal excretion of the ingested Gastrografin was seen in 19 (63%) of the 30 patients, a significantly larger percentage than in the control group (z score, p < 0.01). No patient showed either radiologic or clinical evidence of leakage from the anastomotic site.

CONCLUSION. Renal excretion of ingested Gastrografin is frequently visualized on CT in patients without anastomotic leakage during the early postoperative period after gastric surgery, and this phenomenon is not rare, even in healthy adults. Therefore, renal excretion seen on CT should not be regarded as a sign of anastomotic leakage in early postoperative patients.

OBJECTIVE. The aim of this study was to examine the usefulness of dynamic sonography in the characterization of pancreatic tumors.

MATERIALS AND METHODS. IV contrast-enhanced pancreatic sonography (dynamic sonography) with Levovist was performed in 43 patients with pancreatic mass lesions (32 with pancreatic adenocarcinomas, four with inflammatory pancreatic masses, three with islet cell tumors, two with serous cystadenomas, one with a solid and cystic tumor, and one with metastatic pancreatic cancer). We calculated a contrast index using a time—intensity curve: contrast index equals elevation of intensity in the tumor divided by elevation of intensity in the pancreatic parenchyma. We classified the tumors into three groups according to the contrast index: a slightly enhanced group (contrast index < 0.5), a moderately enhanced group (contrast index = 0.5-1.5), and a well-enhanced group (contrast index > 1.5), and we compared these results with those from dynamic CT.

RESULTS. The contrast indexes of 32 adenocarcinomas, four inflammatory pancreatic masses, three islet cell tumors, two serous cystadenomas, one solid and cystic tumor, and one metastatic tumor were, respectively, 0.12 ± 0.095 (mean ± SD), 0.54 ± 0.420, 1.74 ± 0.555, 1.09 ± 1.380, 1.67, and 2.07. Thirty-five tumors, including all 32 adenocarcinomas, were classified in the slightly enhanced group, three were classified in the moderately enhanced group, and five were classified in the well-enhanced group. In 93% (40/43) of tumors, the grade of enhancement on dynamic sonography was closely correlated with the grade of enhancement on dynamic CT.

CONCLUSION. Dynamic sonography can assist in the characterization of pancreatic tumors.

OBJECTIVE. This study was undertaken as a pilot investigation to compare multidetector CT angiography with conventional catheter angiography for the visualization of the renal artery lumen after renal artery stent placement.

SUBJECTS AND METHODS. CT angiography was performed within 24-48 hr of renal artery stent placement in 15 patients. Two patients had bilateral stens, resulting in a total of 17 stents. CT angiography was performed using a multidetector scanner and a bolus of IV contrast material with the scanning delay determined by a small-volume timing bolus. A volumetric data set was acquired through the stented arteries in the axial plane using a 4.0 × 1.25 mm detector configuration and a pitch of 3:1. The stent lumen diameter, as measured on direct CT angiography and curved multiplanar reformations in both the axial and coronal planes, was compared with that measured on catheter angiography.

RESULTS. The lumina of all 17 stents were well visualized and patent on both CT angiography and catheter angiography. Anatomic definition, including stent position and wall apposition in the renal artery, correlated well with catheter angiography. The diameter of the renal artery stent lumen measured on catheter angiography (mean, 5.9 ± 1.3 mm) was greater than that on CT angiography (mean stent lumen diameter for direct axial plane was 4.6 ± 1.0 mm, for curved multiplanar reformations in the axial plane was 4.3 ± 1.0 mm, and for curved multiplanar reformations in the coronal plane was 4.4 ± 1.0 mm) in 14 (82%) of 17 stents.

CONCLUSION. CT angiography produced interpretable multiplanar images of the renal artery, even with a metallic stent in place, and was adequate for determining stent patency. Compared with catheter angiography, the intrastent luminal diameter was underestimated in most patients who underwent CT angiography.

OBJECTIVE. We performed a study to determine the correlation between the diameter of the echogenic response observed with intraoperative sonography during radiofrequency ablation of the cirrhotic liver and the mean diameter of tissue necrosis.

SUBJECTS AND METHODS. A total of 22 intraoperative radiofrequency ablations were created in 11 cirrhotic livers. The largest diameter of the sonographically observed echogenic response surrounding and perpendicular to the radiofrequency probe was measured. The subsequent zone of necrosis observed at pathology in the hepatectomy specimens after liver transplantation was measured in three planes and compared with the measured diameter of the echogenic response.

RESULTS. During all except three ablations, a hyperechoic region was visualized surrounding the radiofrequency probe. The diameter of the echogenic response correlated significantly with the mean diameter of necrosis (correlation coefficient, 0.84). However, the echogenic response overestimated the minimal diameter of necrosis (mean difference, 0.8 ± 0.4 cm) in 18 of 22 ablations and underestimated the maximum diameter of necrosis (mean difference, 0.9 ± 0.8 cm) in 16 of 22 ablations.

CONCLUSION. The diameter of the echogenic response observed with intraoperative sonography during radiofrequency ablation of the cirrhotic liver correlates closely with the mean diameter of the subsequent area of tissue necrosis. However, the solitary diameter of the echogenic response as measured in our study was often greater than the smallest diameter and less than the largest diameter of the area of tissue necrosis. Therefore, the echogenic response associated with radiofrequency ablation of the cirrhotic liver should be viewed only as a rough approximation of the area of induced tissue necrosis; the final assessment of the adequacy of ablation should be deferred to an alternative imaging technique.

OBJECTIVE. This study evaluated the diagnostic accuracy of high-spatial-resolution sonography in the diagnosis of occult fractures of the waist of the scaphoid.

SUBJECTS AND METHODS. Sonography of the scaphoid bone with a 12-MHz transducer was performed in 54 patients with clinicaly suspected scaphoid fracture and normal findings on initial radiographs, including specific scaphoid images. Three levels of clinical suspicion were considered: high (20%), moderate (30%), and low (50%). Attention was paid to the continuity of the scaphoid cortex and to the surrounding soft tissues (i.e., hemarthrosis or hematoma). Data from early sonograms were then compared with the results of radiography repeated 10-14 days after the initial trauma. In cases of persistent suspicion despite normal findings on follow-up radiographs, the presence of fracture was evaluated on CT (four patients), MR imaging (one patient), or bone scanning (one patient).

RESULTS. Follow-up examinations proved fracture of the scaphoid waist in five patients. In all patients, diagnosis of fracture was suspected on initial sonograms showing cortical disruption associated with soft-tissue abnormalities. There was one false-positive finding and no false-negative results. Using cortical disruption as a diagnostic criterion, we found the sensitivity, specificity, and accuracy of high-resolution sonography for the depiction of scaphoid fracture to be 100%, 98%, and 98%, respectively. Using soft-tissue abnormalities alone as a criterion, we found the sensitivity, specificity, and accuracy of high-resolution sonography to be 100%, 65%, and 68%, respectively. The overall prevalence of occult fracture was 9%, ranging from 3.7% for low suspicion to 27% for high suspicion of fracture.

CONCLUSION. High-resolution sonography is a reliable and accurate method of evaluating occult fractures of the scaphoid waist. Cortical disruption is the diagnostic key. Soft-tissue abnormalities alone lack specificity.

OBJECTIVE. The purpose of our study was to identify the characteristic MR imaging features of intramuscular myxoma.

MATERIALS AND MATERIALS. We retrospectively reviewed the MR imaging features of 20 patients with intramuscular myxoma. Clinical assessment included the age and sex of the patient and location of the tumor. Radiologic evaluation included the lesion size and shape, border definition, signal on T1- and T2-weighted or fluid-sensitive MR sequences, enhancement pattern, presence or absence of a fat rind, and presence or absence of increased signal in the adjacent muscle on T2-weighted or fluid-sensitive MR sequences.

RESULTS. The mean age of patients presenting with intramuscular myxoma was 61 years (range, 15-85 years; median, 64 years). The mean lesion size was 6.9 cm (range, 3-17 cm; median, 6.3 cm). A peritumoral fat rind was present in 13 of the patients (65%) with myxoma, and an increased signal in the adjacent muscle on fluid-sensitive sequences was present in 11 patients (55%). Intramuscular myxomas were homogeneously low in signal intensity on T1-weighted MR sequences in 19 patients (95%), with all lesions showing a high signal intensity on T2-weighted or fluid-sensitive MR sequences. Twelve of the myxomas had well-defined borders, and eight had borders that were partially ill defined. Of the 11 lesions imaged after gadolinium administration, six (55%) showed intense heterogeneous enhancement.

CONCLUSION. Findings of a mass that on MR images shows a perilesional fat rind, the signal intensity of fluid, and an increased signal in the adjacent muscle on T2-weighted or fluid-sensitive MR sequences are strongly suggestive of intramuscular myxoma. The degree of lesion enhancement varies but is most frequently intense and heterogeneous. Although the recognition of these features likely will not obviate biopsy of any individual lesion, it will allow more accurate prebiopsy diagnosis and preoperative planning.

OBJECTIVE. We proposed to characterize the radiologic spectrum of occipital condyle fractures in a large series of patients and to correlate fracture pathology with neurosurgical treatment and patient outcome.

MATERIALS AND METHODS. We conducted a retrospective review of the findings on conventional radiography, CT, and MR imaging in 95 patients with 107 occipital condyle fractures. We described fracture patterns according to two previously published classification systems. Clinical findings, neurosurgical management, and patient outcome were obtained from the medical records.

RESULTS. Inferomedial avulsions (Anderson and Montesano type III) were the most common type of occipital condyle fracture, constituting 80 (75%) of 107 overall fractures. Unilateral occipital condyle fractures were found in 73 (77%) of 95 patients, and 58 patients were treated nonoperatively; occipitocervical fusion was required in nine patients for complex C1-C2 injuries, and six patients died. Bilateral occipital condyle fractures or occipitoatlantoaxial joint injuries were seen in 22 (23%) of 95 patients. Occipitocervical fusion or halo traction for the craniocervical junction was required in 12 patients, all of whom had CT evidence of bilateral occipitoatlantoaxial joint disruption and six of whom showed normal craniocervical relationships on conventional radiographs. Six patients with nondisplaced fractures were treated nonoperatively, and four patients died. Thirty (32%) of 95 patients showed continued disability, whereas 55 (57.5%) of 95 patients had good outcomes at 1 month. Associated cervical spine injuries were present in 29 (31%) of 95 patients.

CONCLUSION. Given their associated traumatic brain and cervical spine injuries, occipital condyle fractures are markers of high-energy traumas. That conventional radiographs alone may miss up to half of the patients with acute craniocervical instability has not been well established. Avulsion fracture type and fracture displacement are associated with both injury mechanism and the need for surgical stabilization. In this series, most unilateral occipital condyle fractures were treated nonoperatively, whereas bilateral occipitoatlantoaxial joint injuries with findings of instability usually required surgical stabilization.

OBJECTIVE. The purpose of this study is to describe the imaging features of cardiac arrest that occur during CT.

CONCLUSION. CT features of cardiac arrest are characterized by a pooling of contrast agent in the dependent parts of the right side of the body, including the venous system and the right lobe of the liver. If medical professionals are aware of these specific imaging features, prompt cardiac resuscitation can be initiated to avoid permanent brain damage and death.

OBJECTIVE. The purpose of this report is to describe the clinical, CT, and pathologic features of non-Hodgkin's lymphoma of the vermiform appendix.

CONCLUSION. Non-Hodgkin's lymphoma of the appendix typically manifests with acute symptoms in patients who have no prior history of lymphoma. Most patients with the disease present clinically with signs and symptoms suggestive of acute appendicitis. On CT, lymphomatous infiltration of the appendix produces markedly diffuse mural soft-tissue thickening (range of diameters, 2.5-4.0 cm; mean diameter, 3.2 cm). The vermiform morphology of the appendix is usually maintained, and aneurysmal dilatation of the lumen is sometimes seen. Stranding of the periappendiceal fat seen on CT may represent superimposed inflammation or even direct lymphomatous extension. Coexisting abdominal lymphadenopathy is not seen in all patients. Although appendiceal lymphoma is rare, the characteristic CT appearance could lead to a preoperative diagnosis.

OBJECTIVE. Our aim is to evaluate the feasibility, efficacy, and patency of using coronary stents for the treatment of hepatic artery stenosis after liver transplantation.

CONCLUSION. Hepatic artery stenosis after liver transplantation can be treated using coronary stents. The low rate of complication, high technical success, and 1-year patency rates are encouraging.

OBJECTIVE. The purpose of this study was to review the imaging findings of children referred for cross-sectional imaging to evaluate persistent airway symptoms after surgical therapy for double aortic arch.

CONCLUSION. Airway narrowing is clearly shown on cross-sectional imaging in patients with persistent airway symptoms after surgical therapy for double aortic arch. Two patterns of airway compression are typically seen: narrowing of the trachea at the level of the postsurgical arch and narrowing of the left main bronchus as a result of compression from a midline descending aorta. Both patterns may be seen in patients regardless of whether the left or the right arch has been ligated.

OBJECTIVE. Our purpose was to describe the use of MR imaging in the evaluation of the positions of the popliteal artery and peroneal nerve in children with popliteal pterygium syndrome for preoperative planning and to describe the typical appearance of popliteal pterygium on MR imaging.

CONCLUSION. By depicting the popliteal artery and peroneal nerve either in normal positions or abnormally located immediately adjacent to the pterygium, MR imaging provides useful information for preoperative planning in children with popliteal pterygium syndrome. The MR appearance of a popliteal pterygium is that of a band of abnormal tissue extending from the ischium to the os calcis that has signal characteristics of fibrous tissue often attached to a belly of anomalous muscle.

OBJECTIVE. We used pullback pressure measurements to identify venous stenoses persisting after angioplasty of failing hemodialysis grafts.

MATERIALS AND METHODS. Fifty angioplasty procedures were performed in 32 patients with elevated venous pressures at dialysis. Grafts were initially evaluated on digital subtraction angiography, and all stenoses measuring greater than 50% on angiography underwent angioplasty. In successful cases (residual stenosis < 30%), pullback pressure measurements were obtained from the superior vena cava to the graft to identify hemodynamically significant (> 10 mm Hg) stenoses. These lesions were then treated with repeated angioplasty.

RESULTS. Hemodynamically significant stenoses with a gradient range of 10-27 mm Hg (mean, 16 mm Hg) were found in nine (18%) of 50 procedures. All gradients occurred at sites of previous angioplasty. Repeated angioplasty of these stenoses performed with larger angioplasty balloons reduced gradients to less than 3 mm Hg in six stenoses and to 5 mm Hg in three stenoses. In this subgroup, primary patency was eight (89%) of nine stenoses at 1 month and 2 months and five (56%) of nine stenoses at 6 months. Using life table analysis, we found that primary patency of the entire population was 84% at 1 month, 66% at 2 months, and 47% at 6 months. The mean time between interventions was 6 months, and the thrombosis rate was 0.32 per year.

CONCLUSION. Pullback pressure measurements are a useful adjunct to angiography to evaluate the hemodynamic results of angioplasty in patients with failing hemodialysis grafts.

OBJECTIVE. This study was performed to evaluate the clinical efficacy, feasibility, and complications of balloon-occluded retrograde transvenous obliteration for patients with hemorrhage from gastric fundal varices.

SUBJECTS AND METHODS. Between December 1994 and February 2001, 24 consecutive patients with hemorrhage from gastric fundal varices were enrolled in this study. Balloon-occluded retrograde transvenous obliteration consisted of injecting 5% ethanolamine oleate iopamidol through the outflow vessels during balloon occlusion. The treatment was performed during acute bleeding in 11 patients and electively in 13 patients. Among those patients with acute bleeding, six were treated for temporary hemostasis with balloon tamponade, and five were treated endoscopically.

RESULTS. Cannulation into the outflow vessels was performed in 23 patients, but the balloon catheter could not be inserted in one patient who had inferior phrenic vein outflow. Complete success was obtained in 88% (21/24) of patients, and partial success was obtained in two patients. In nine of 11 patients with acute bleeding, complete success was achieved. Rebleeding from gastric varices was not observed in patients treated with complete success, whereas two patients treated partially rebled within 1 week of the treatment (rate of rebleeding, 9%). Eradication of gastric varices was obtained in all patients (n = 19) who were examined by endoscopy 3 months after the treatment. Eight patients experienced worsening of esophageal varices. These patients were treated endoscopically because of findings that suggested a risk of hemorrhage. The overall mortality rate was 4% (1/24). No damage to the kidney was observed, although 11 patients had macrohematuria.

CONCLUSION. Balloon-occluded retrograde transvenous obliteration followed by any hemostatic procedure might be effective for both prophylaxis of rebleeding and eradication of gastric fundal varices, even in urgent cases.

OBJECTIVE. Our purpose was to evaluate prospectively whether MR imaging, including dynamic contrast-enhanced MR imaging, could be used to categorize peripheral vascular malformations and especially to identify venous malformations that do not need angiography for treatment.

SUBJECTS AND METHODS. In this blinded prospective study, two observers independently correlated MR imaging findings of 27 patients having peripheral vascular malformations with those of diagnostic angiography and additional venography. MR diagnosis of the category, based on a combination of conventional and dynamic contrast-enhanced MR parameters, was compared with the angiographic diagnosis using gamma statistics. Sensitivity and specificity of conventional MR imaging and dynamic contrast-enhanced MR imaging in differentiating venous from nonvenous malformations were determined.

RESULTS. Excellent agreement between the two observers in determining MR categories (γ = 0.99) existed. Agreement between MR categories and angiographic categories was high for both observers (γ = 0.97 and 0.92). Sensitivity of conventional MR imaging in differentiating venous and nonvenous malformations was 100%, whereas specificity was 24-33%. Specificity increased to 95% by adding dynamic contrast-enhanced MR imaging, but sensitivity decreased to 83%.

CONCLUSION. Conventional and dynamic contrast-enhanced MR parameters can be used in combination to categorize vascular malformations. Dynamic contrast-enhanced MR imaging allows diagnosis of venous malformations with high specificity.