Physician knowledge and appropriate utilization of computed tomographic colonography in colorectal cancer screening.

GOALS: To assess physician understanding of computed tomographic colonography (CTC) in colorectal cancer (CRC) screening guidelines in a pilot study. BACKGROUND: CTC is a sensitive and specific method of detecting colorectal polyps and cancer. However, several factors have limited its clinical availability, and CRC screening guidelines have issued conflicting recommendations. STUDY: A web-based survey was administered to physicians at two institutions with and without routine CTC availability. RESULTS: 398 of 1655 (24%) participants completed the survey, 59% was from the institution with routine CTC availability, 52% self-identified as trainees, and 15% as gastroenterologists. 78% had no personal experience with CTC. Only 12% was aware of any current CRC screening guidelines that included CTC. In a multiple regression model, gastroenterologists had greater odds of being aware of guidelines (OR 3.49, CI 1.67-7.26), as did physicians with prior CTC experience (OR 4.81, CI 2.39-9.68), controlling for institution, level of training, sex, and practice type. Based on guidelines that recommend CTC, when given a clinical scenario, 96% of physicians was unable to select the appropriate follow-up after a CTC, which was unaffected by institution. CONCLUSIONS: Most physicians have limited experience with CTC and are unaware of recent recommendations concerning CTC in CRC screening.

Bedside use of a dual aortic balloon occlusion for the treatment of cerebral vasospasm.

BACKGROUND: Delayed ischemic neurological deficits (DIND) due to cerebral vasospasm remains a major cause of morbidity and mortality following aneurysmal subarachnoid hemorrhage (aSAH). Methods to prevent DIND remain limited both in safety and efficacy. A novel intra-aortic dual balloon catheter (NeuroFlo™: CoAxia, Maple Grove, MN) is under investigation for treatment of ischemic stroke, including DIND. Because this technique does not require cerebral artery navigation, it may be useful as a bedside procedure, outside of the conventional angiography suite. We report the first case of ultrasound-guided application of the NeuroFlo™ system at bedside in the Neurological Intensive Care Unit. METHODS: A 52-year-old woman presented with Hunt Hess IV aSAH complicated by medically refractory cerebral vasospasm. Despite surgical clipping of her aneurysm, the patient remained critically ill, failing maximal conventional medical therapy. For that reason, the NeuroFlo™ system was deployed using two-dimensional, spectral and color-flow Doppler ultrasound guidance at the patient's bedside while maintaining all forms of cerebral blood flow monitoring. RESULTS: The procedure was well tolerated and there was no complication. CONCLUSION: Bedside application of the NeuroFlo™ system may be safely performed in critically ill patients. The NeuroFlo™ system is under investigation for treatment of refractory cerebral vasospasm to prevent delayed ischemic neurological disease.

Features of nephrogenic systemic fibrosis on radiology examinations.

OBJECTIVE: The objective of this article is to illustrate the spectrum of imaging findings with photographic and histopathologic correlation in patients with biopsy-proven nephrogenic systemic fibrosis (NSF). CONCLUSION: Features of NSF may be evident on the patient's skin as well as on routine imaging studies, although these imaging findings are nonspecific and are more likely to occur with other diseases.

Nephrogenic systemic fibrosis and its impact on abdominal imaging.

The objective of this article is to review the current knowledge about nephrogenic systemic fibrosis (NSF) and how to prevent it. More than 300 cases of NSF in patients with severe chronic renal insufficiency or acute renal failure or in patients undergoing dialysis have been reported in the peer-reviewed literature, with an overwhelming majority occurring within weeks to months after injection of a gadolinium-based contrast agent (GBCA). Because administration of a high dose of a GBCA is a primary risk factor and because most high-dose magnetic resonance (MR) imaging applications involve abdominal imaging (eg, liver and abdominal MR angiography), NSF cases have been associated with abdominal MR imaging. Additional major risk factors for developing NSF include proinflammatory conditions, failure to perform dialysis promptly after GBCA administration, use of nonionic linear contrast agents, hyperphosphatemia, and younger age. Recent recommendations to use GBCAs with caution in patients with acute renal failure, patients receiving dialysis, or patients with an estimated glomerular filtration rate of less than 30 mL/min have resulted in virtually no new NSF cases being reported with onset in 2008 or 2009 in spite of a high level of awareness about this entity. In conclusion, NSF has been virtually eliminated by using caution in administering GBCAs to patients known to have severe or acute renal failure. In these patients, avoid high doses; and for patients undergoing dialysis, schedule MR imaging to occur just before a dialysis session to ensure rapid elimination of gadolinium.

Transplantation-mediated alloimmune thrombocytopenia: Guidelines for utilization of thrombocytopenic donors.

Transplantation-mediated alloimmune thrombocytopenia (TMAT) is donor-derived thrombocytopenia following solid-organ transplantation. To date, no clear consensus on the appropriateness of organ utilization from cadaver donors with a history of idiopathic thrombocytopenia purpura (ITP) has emerged. Herein is reported a devastating case of TMAT following liver transplantation utilizing an allograft from a donor with ITP that resulted in allograft failure. The literature is reviewed in this context to propose preliminary guidelines regarding utilization of allografts from cadaver donors with a history of ITP.

Outflow reconstruction in right hepatic live donor liver transplantation.

BACKGROUND: Inconstant venous anatomy increases the risk of outflow complications in right hepatic live donor liver transplantation (RH-LDT), but no consensus has emerged guiding optimal reconstruction for venous outflow. METHODS: We retrospectively analyzed surgical venous reconstruction using a flexible approach to anterior accessory veins in 48 RH-LDTs performed between April, 1998 and July, 2002. RESULTS: Actuarial recipient graft and patient survival was 79% and 85%, respectively. Single hepatic venous anastomosis was performed in 74% of the patients. Twelve patients underwent reconstruction of 20 accessory veins, including 7 posterior segment veins and 13 anterior segment veins. Anterior vein reconstruction techniques included end-to-end anastomosis to the middle hepatic vein, interposition conduit, venoplasty, or a combination of techniques. Documented complications related to the venous anastomosis occurred in only 1 patient (2%), with no patient having a documented venous thrombosis of either the main RHV or a reconstructed accessory vein. There were no differences in outcome based on single versus multiple venous reconstruction. Anteromedial congestion was noted in 3 patients in the absence of anatomic venous anastomotic complication, but the clinical significance of this finding is unclear. CONCLUSIONS: Despite variations in segmental venous drainage and a propensity for anteromedial congestion in right hepatic grafts, RH-LDT can be performed without outflow obstruction with close attention to a wide RHV anastomosis. In addition, anterior accessory vein reconstruction can be reserved for grafts of marginal size or quality where early postoperative venous congestion may impair early graft function. Routine extended hepatectomy incorporating the MHV with the graft is unnecessary.

Changes in hepatic venous morphology with cirrhosis on MRI.

PURPOSE: To identify changes in vascular morphology on magnetic resonance imaging (MRI) in patients with cirrhosis and to compare these findings to liver donors. MATERIALS AND METHODS: Patients undergoing liver transplantation with biopsy-proven cirrhosis (n = 74) and liver donor candidates (n = 85) underwent dynamic gadolinium-enhanced 3D MR at 1.5T. Vessel diameters were measured independently by three radiologists and features of cirrhosis were identified and correlated with cirrhosis. RESULTS: Hepatic veins were smaller in patients with cirrhosis (4.9, 4.5, and 5.0 mm for right, middle, and left vs. 9.9, 7.6, and 8.9 mm in donors, P << 0.001) and were negatively correlated with cirrhosis (P < 0.001). Right hepatic vein (RHV) <5 mm diagnosed cirrhosis with 59% sensitivity and 99% specificity; the sensitivity and specificity were 88% and 85% for RHV <7 mm. Main portal vein was minimally larger in cirrhosis, 14 versus 12 mm (P < 0.001) in donors. Right portal veins were smaller in cirrhotic patients, 6.5 and 6.2 mm compared to 8.4 and 7.6 mm (P << 0.001), respectively, in donors. CONCLUSION: Vascular features of cirrhosis include small hepatic veins, minimally enlarged main portal vein, and small intrahepatic portal veins; these features may facilitate identification of cirrhosis.