Multiphasic contrast-enhanced MRI: single-slice versus volumetric quantification of tumor enhancement for the assessment of renal clear-cell carcinoma fuhrman grade.

PURPOSE: To assess the association between clear-cell carcinoma pathology grade at nephrectomy and magnetic resonance imaging (MRI) tumor enhancement. MATERIALS AND METHODS: The Institutional Review Board approved this retrospective study and waived the informed consent requirement. In all, 32 patients underwent multiphase contrast-enhanced MRI prior to nephrectomy. MRI tumor enhancement was measured using two approaches: 1) the most enhancing portion of the tumor on a single slice and 2) volumetric analysis of enhancement in the entire tumor. Associations between pathological grade, tumor size, and enhancement were evaluated using the Kruskal-Wallis test and generalized logistic regression models. RESULTS: No significant association between pathology grade and enhancement was found when measurements were made on a single slice. When measured in the entire tumor, significant associations were found between higher pathology grades and lower mean, median, top 10%, top 25%, and top 50% tumor enhancement (P < 0.001-0.002). On multivariate analysis the association between grade and enhancement remained significant (P = 0.041-0.043), but tumor size did not make an additional contribution beyond tumor enhancement alone in differentiating between tumor grades. CONCLUSION: There is significant association between tumor grade and enhancement, but only when measured in the entire tumor and not on the most enhancing portion on a single slice.

Pancreatic involvement in neuroblastoma with radiologic-pathologic correlation: a single-institution experience.

OBJECTIVE: Pancreatic involvement in neuroblastoma is extremely rare, with few cases reported in the literature. We present imaging findings of pancreatic involvement in neuroblastoma with clinical and pathologic correlation in the largest documented series to date. SUBJECTS AND METHODS: We prospectively reported pancreatic involvement evident on multimodality imaging in neuroblastoma patients presenting to our institution from 1997 to 2011. Lesions were classified according to location within the pancreas, and imaging features were correlated with cytogenetic and surgicopathologic findings. RESULTS: Neuroblastoma involving the pancreas was evident on imaging of seven of 1031 patients (mean age, 6.6 years). One patient had pancreatic involvement at presentation, and six developed pancreatic disease at relapse or disease progression. Pancreatic lesions were most frequently initially identified on concurrent CT and (123)I-metaiodobenzylguanidine scintigraphy, and additional lesions initially were found on MRI and ultrasound. Five of seven patients had focal lesions, one had diffuse pancreatic involvement, and one had pancreatic extension from contiguous disease. The distribution of lesions favored the pancreatic body and tail. All patients had International Neuroblastoma Staging System stage 3 or 4 disease, Children's Oncology Group intermediate- or high-risk disease, and unfavorable histology at initial diagnosis. For the five patients with surgical correlation, pancreatic surgical specimens revealed neuroblastoma in three cases and ganglioneuroblastoma in two cases. CONCLUSION: Although rare, pancreatic involvement in neuroblastoma occurs. Its variable imaging appearance should be considered when evaluating the retroperitoneum in patients with known or suspected neuroblastoma, particularly because increased patient survival holds the potential for uncommon patterns of recurrence.

Isolated pharmacomechanical thrombolysis plus primary stenting in a single procedure to treat acute thrombotic superior vena cava syndrome.

PURPOSE: To report a combined procedure that opens the acutely thrombosed superior vena cava (SVC) to rapidly alleviate symptoms in seriously ill patients with SVC syndrome. CASE REPORTS: Four patients aged 54 to 63 years old with underlying malignancies were referred for treatment of SVC syndrome. All received isolated pharmacomechanical thrombolysis (IPMT) with tissue plasminogen activator delivered in a Trellis Peripheral Infusion System that removed obstructive clot in minutes versus the 24 to 48 hours required for traditional catheter-directed thrombolysis. In each case, stents were inserted immediately following IPMT in a combined procedure lasting <1 hour. Patients exhibited near-immediate relief of debilitating symptoms; completion venography demonstrated patent vessels with excellent blood flow. CONCLUSION: Combining IPMT with immediate stenting during the same session is an effective method for managing acute thrombotic SVC syndrome and limiting the exposure time and number of interventions performed on seriously ill patients.

Hypotonic MR duodenography with water ingestion alone: feasibility and technique.

To date, cross-sectional imaging of the duodenum has a number of inadequacies, most likely a reflection of its tortuous and complex anatomical course, resulting in somewhat suboptimal imaging. The purpose of this study was to describe and assess the feasibility of performing a 'tubeless', per-oral, single contrast, hypotonic magnetic resonance (MR) duodenography technique. Secondly, to assess the efficacy of intravenous Buscopan in facilitating duodenal distension at cross-sectional MR imaging. Ten healthy volunteers prospectively underwent MR imaging of the duodenum pre- and post-Buscopan immediately after consuming 1,000 ml of water. Images were qualitatively (using a visual assessment grading scale of 1-3) and quantitatively evaluated with regard to degree of small bowel distension by two observers. The contrast medium was successfully ingested and MR examination was completed in all participants. Quantitatively and qualitatively, the per-oral, hypotonic duodenography technique yielded superior distension scores and was significantly greater in diameter in comparison with the per-oral non-hypotonic duodenography technique (p < 0.003, p < 0.002). Per-oral, single-contrast, hypotonic MR duodenography is a feasible, simple, fast mode of investigation of the duodenum, which does not involve radiation and represents a useful technique in the armamentarium of the radiologist.

Duodenal abnormalities at MR small-bowel follow-through.

OBJECTIVE: The cross-sectional characterization of duodenal abnormalities is plagued with inadequacy, a reflection of the meandering course of this segment of the bowel. We consider the imaging appearance of such abnormalities at MRI small-bowel follow-through, illustrating the typical manifestations of each pathologically confirmed condition. CONCLUSION: MRI small-bowel follow-through allows confident duodenal evaluation because of a combination of sufficient luminal distention and multiplanar versatility. Diseases of the duodenum may have a variety of manifestations at MRI small-bowel follow-through, the knowledge of which may aid in confident noninvasive patient diagnosis.

Normal small bowel wall characteristics on MR enterography.

PURPOSE: To assess the normal small bowel parameters, namely bowel diameter, bowel wall thickness, number of folds (valvulae connivientes) per 2.5 cm (in.), fold thickness and interfold distance per small bowel segment (duodenum, jejunum, proximal ileum, distal ileum and terminal ileum) on MR enterography. MATERIALS AND METHODS: Between September 2003 and January 2008, 280 MR enterography examinations were performed for investigation of known or suspected small bowel pathology. 120 of these examinations were normal. Sixty-five (m=29, f=36, mean age=34 years, range=17-73 years) of 120 examinations without a prior small bowel diagnosis, with no prior or subsequent abnormal radiology or endoscopy examinations, no prior small bowel surgery and with a minimum 3 years follow-up demonstrating normality were retrospectively evaluated for the described small bowel parameters. RESULTS: We found the mean diameter of the duodenum to be 24.8mm (S.D.=4.5mm), jejunum to be 24.5mm (S.D.=4.2mm), proximal ileum to be 19.5mm (S.D.=3.6mm), distal ileum to be 18.9 mm (S.D.=4.2mm) and terminal ileum to be 18.7 mm (S.D.=3.6mm). The number of folds per 2.5 cm varied from 4.6 in the jejunum to 1.5 in the terminal ileum. The fold thickness varied from 2.1mm in the duodenum to 1.8mm in the terminal ileum. The small bowel parameters gradually decreased in size from the duodenum to the smallest measurements which were in the terminal ileum. The bowel wall is similar in size throughout the small bowel measuring 1.5+/-0.5mm. CONCLUSION: These results provide the mean, range of normality and standard deviation of the small bowel parameters per segment on the current population on MR enterography. From our experience, knowledge of these parameters is extremely helpful and essential in the everyday assessment of MR enterography studies.

Anatomy, pathology, imaging and intervention of the iliopsoas muscle revisited.

The apparent incidence of iliopsoas muscle abnormalities is currently rapidly increasing secondary to the increased number of immuno-compromised patients, malignancies, chemotherapy, immunotherapy, multi-systemic disease and the wide availability of cross-sectional imaging. Disease of the iliopsoas compartment can present with non-specific or indolent clinical features, particularly where normal immune responses are attenuated. Delay in diagnosis can lead to inappropriate initial treatment and, in some cases, serious complications. Wider availability and application of modern cross-sectional imaging offers rapid, confident diagnosis. An understanding of iliopsoas compartment anatomy and pathways of disease spread are essential to recognising these clinically important conditions. We review the anatomy, clinical presentation and common imaging findings of iliopsoas disease as it presents through the emergency room.

Stent implantation across the ostia of the renal veins does not necessarily cause renal impairment when treating inferior vena cava occlusion.

The effect of inferior vena cava (IVC) stents crossing the ostia of the renal veins on renal function has not been reported. The purpose of this study is to report a single-institution experience with four cases of IVC stent implantation for malignant compression and/or invasion of the IVC causing severe lower-extremity edema. The patients' symptoms were successfully relieved, and follow-up imaging and serum creatinine measurements for the remainder of their lives revealed no evidence of renal impairment or renal vein thrombosis.