Faculty Bibliography

Rhabdoid tumor of the kidney (RTK) is a rare pediatric malignancy. Its imaging features by ultrasound and CT have been well described; however, to our knowledge, there are only a handful of case reports that describe the MR appearance of rhabdoid tumor. We report the MR appearance of a RTK in an 18-month-old boy, review the literature on its imaging features, and discuss the differential diagnosis of solid renal tumors in children.

Sclerosing hemangioma (SH) is a relatively rare, benign neoplasm of the lung. Although there are relatively characteristic imaging findings, biopsy remains the definitive diagnostic test. We report the radiology and pathology of a patient with a SH, with emphasis on the computed tomographic and (18)F-fluorodeoxyglucose positron emission tomography findings, and review the literature on this unusual tumor.

STUDY DESIGN/METHODS:A retrospective radiographic study involving analysis of abdominal and pelvic computed tomography (CT) scans obtained on patients presenting with clinical conditions other than back pain. OBJECTIVE:To determine the incidence of spondylolysis and spondylolisthesis in patients requiring inpatient or emergency department CT evaluation for unrelated abdominal and pelvic conditions. SUMMARY OF BACKGROUND DATA/BACKGROUND:Spondylolysis and spondylolisthesis are part of a disease process that is thought to be resultant from biomechanical stresses related to bipedal locomotion. The incidence is estimated to be 3% to 10% in the general population. Many of these cases occur without associated symptoms. To our knowledge, there is a relative paucity of data on the use of CT to evaluate the prevalence of these 2 entities in patients seeking medical attention for unrelated conditions. METHODS:Five hundred ten consecutive abdominal and pelvic multi-detector CT scans obtained on a single scanner (Philips MX8000; Eindhoven, The Netherlands) were reviewed. These patients presented with such complaints as abdominal pain and fever, or were imaged as part of their inpatient evaluation for conditions unrelated to lumbar spine pathology. A board certified radiologist and a radiology resident retrospectively evaluated CT scans for lumbar spondylolysis, spondylolisthesis, and associated degenerative changes. A neuroradiologist confirmed all positive cases. RESULTS:Of the 510 cases examined, there were 29 cases of spondylolysis at L5, corresponding to a prevalence of 5.7%. Twenty-three of the cases demonstrated bilateral spondylolysis and 6 unilateral. Sixteen of the 23 cases of bilateral spondylolysis also had spondylolisthesis, 13 of which were grade I, and 3 of which were grade II. In patients 45 years old and younger who did not have spondylolysis or spondylolisthesis, we observed a 32.2% incidence of sclerosis involving the L5 lumbar pedicles. CONCLUSIONS:This study demonstrates a 5.7% prevalence of spondylolysis and a 3.1% prevalence of spondylolisthesis in patients undergoing CT scans of the abdomen and pelvis for unrelated reasons, corresponding to the rate of spondylolysis and spondylolisthesis detected in prospective plain radiographic studies. We observed a 1.2% incidence of unilateral spondylolysis, and approximately 67% of these demonstrated contralateral sclerosis. It is suggested in the literature that sclerosis of the contralateral pedicle seen in cases of unilateral spondylolysis may be a compensatory response to mechanical stresses on an unstable lumbar vertebral body.

Acinar cell carcinoma (ACC) is a rare tumor that constitutes 1% of pancreatic neoplasms. ACC is defined as a carcinoma exhibiting pancreatic enzyme production by neoplastic cells. Clinical presentation is usually related to either local spread or metastasis. In this Radiology-Pathology Conference, the clinical presentation and imaging findings of a patient with ACC of the pancreas, along with the differential diagnosis, are reviewed.

The postprocedural period is a critical time in which serious complications can manifest. Localization of suspected complications following abdominal and pelvic procedures can be difficult on clinical evaluation alone. For example, abdominal pain after a colonoscopy may vary in etiology and can result from simple colonic spasm to colonic perforation, hemoperitoneum, or even splenic rupture. Vague abdominal pain following a renal biopsy may be due to minimal postprocedural bleeding into and around the kidney or may be due to potentially life-threatening hemorrhage. In such patients, computed tomography can play a crucial role in the rapid identification of complications as well guidance of subsequent patient management. The purpose of this article is to demonstrate the benefit of computed tomography-assisted diagnosis of complications associated with routine procedures performed on or throughout the abdomen and pelvis, including cardiac catheterization, colonoscopy, endoscopy, percutaneous biopsy, and interventional radiology procedures

OBJECTIVES/OBJECTIVE:To develop predictive models of recovery from the vegetative state (VS) and minimally conscious state (MCS) after traumatic brain injury (TBI) and to gather preliminary evidence on the impact of various psychotropic medications on the recovery process to support future randomized controlled trials. Design Longitudinal observational cohort design, in which demographic information, injury and acute care history, neuroimaging data, and an initial Disability Rating Scale (DRS) score were collected at the time of study enrollment. Weekly follow-up data, consisting of DRS score, current psychoactive medications, and medical complications, were gathered until discharge from inpatient rehabilitation. SETTING/METHODS:Seven acute inpatient rehabilitation facilities in the United States and Europe with specialized programs for treating patients in the VS and MCS. PARTICIPANTS/METHODS:People with TBI (N=124) who were in the VS or MCS 4 to 16 weeks after injury. INTERVENTIONS/METHODS:Not applicable. MAIN OUTCOME MEASURES/METHODS:DRS score at 16 weeks after injury and time until commands were first followed (among those participants demonstrating no command following at study enrollment). Results DRS score at enrollment, time between injury and enrollment, and rate of DRS change during the first 2 weeks of poststudy observation were all highly predictive of both outcomes. No variables related to injury characteristics or lesions on neuroimaging were significant predictors. Of the psychoactive medications, amantadine hydrochloride was associated with greater recovery and dantrolene sodium was associated with less recovery, in terms of the DRS score at 16 weeks but not the time until commands were followed. More detailed analysis of the timing of functional improvement, with respect to the initiation of amantadine provided suggestive, but not definitive, evidence of the drug's causal role. CONCLUSIONS:These findings show the feasibility of improving outcome prediction from the VS and MCS using readily available clinical variables and provide suggestive evidence for the effects of amantadine and dantrolene, but these results require confirmation through randomized controlled trials.

This article reviews the research to date, as well as our clinical experience from two institutions, on gadolinium-enhanced computed tomographic angiography (gCTA) for imaging the body. gCTA may be an appropriate examination for the small percentage of patients who would benefit from noninvasive vascular imaging, but who have contraindications to both iodinated contrast and magnetic resonance imaging. gCTA is more expensive than CTA with iodinated contrast, due to the dose of gadolinium administered, and gCTA has limitations compared with CTA with iodinated contrast, in that parenchymal organs are not optimally enhanced at doses of 0.5 mmol/kg or lower. However, in our experience, gCTA has been a very useful problem-solving examination in carefully selected patients. With the advent of 16-64 detector CT, in combination with bolus tracking, we believe that the overall dose of gadolinium needed for diagnostic CTA examinations, while relatively high, can be safely administered.