Histopathologic evaluation of tissue extracted on the radiofrequency probe after ablation of liver tumors: preliminary findings.

OBJECTIVE: Our aim was to evaluate the histologic characteristics of tissue extracted on the probe immediately after radiofrequency ablation of malignant tumors in the liver. MATERIALS AND METHODS: From April to December 2001, 20 radiofrequency ablations were performed in 19 patients with primary (n = 17) and metastatic (n = 2) liver masses. Track ablation according to device protocol was performed after each ablation. Tissue was adherent to the probe after all radiofrequency probe passes. All pieces of tissue found on the probe were collected and preserved in formalin. RESULTS: Tissue was examined by the study pathologist. In eight (40%) of 20 specimens, coagulation necrosis was present. In five (25%) of 20 specimens, possibly nonviable tissue was extracted, although some cell characteristics were identified. In seven (35%) of 20 specimens with hepatocellular carcinoma, possibly viable tissue was found. Five specimens were identified as hepatocellular carcinoma, and two, as cirrhotic nodules. CONCLUSION: Histopathologic evaluation of the tissue extracted on the radiofrequency probe after ablation is feasible. This study showed that coagulation necrosis was clearly present in at least 40% of the patients, which proves that nonviable tissue can be seen immediately after ablation. Whether this pathologic finding has prognostic value is not known.

Angiographic embolization for liver injuries: low mortality, high morbidity.

OBJECTIVE: Angiographic embolization (AE) is a safe and effective method for controlling hemorrhage in both blunt and penetrating liver injuries. Improved survival after hepatic injuries has been documented using a multimodality approach; however, patients still have significant long-term morbidity. This study examines further the role of AE in both blunt and penetrating liver injuries and the outcomes of its use. METHODS: The medical records of 37 consecutive patients admitted from 1995 to 2002 to a Level I trauma center who underwent hepatic angiography with the intent to embolize were reviewed. Demographic and clinical information including Injury Severity Score, length of stay, mortality, intra-abdominal complications, admission physiologic variables, and the number and type of abdominal operations performed were collected. RESULTS: Thirty-seven patients underwent hepatic angiography and 26 patients had hepatic embolization performed. Eleven patients underwent early-AE, immediately after computed tomographic scanning, and 15 underwent late-AE, after liver-related operations or later in their hospital course. There was a 27% mortality rate overall. There were 11 liver-related complications in the 26 embolizations. Excluding the early deaths, the associated morbidity was 58%, which included hepatic necrosis, hepatic abscesses, and bile leaks. CONCLUSION: There is increasing adjunctive use of AE in patients managed both operatively and nonoperatively. Intra-abdominal complications are common in these salvaged patients with severe liver injuries. Those patients that underwent early-AE received significantly fewer blood transfusions and more commonly had sterile hepatic collections. Only 26% of patients required liver-related surgery after AE. Therefore, the integration of AE as an adjunctive modality for patients with high-grade liver injuries is a safe and effective therapeutic option.

Alteplase for hemodialysis access graft thrombolysis.

PURPOSE: To evaluate the efficacy and safety of alteplase, a recombinant tissue plasminogen activator, in hemodialysis access graft thrombolysis. MATERIALS AND METHODS: From November 1999 to May 2001, 68 episodes of occlusion in 50 grafts (in 49 patients) were included in the study. Occlusion was treated with pulse-spray (n = 41) or lyse-and-wait (n = 27) thrombolysis with use of alteplase. Balloon angioplasty of all identified stenoses was performed. The arterial plug was mobilized with the Fogarty maneuver. RESULTS: Procedural success was achieved in 64 of 68 episodes (94%) with a dose of 2-10 mg (mean = 4.13 mg) of alteplase, allowing successful hemodialysis within 24 hours. Failures (6%) were the result of PTA perforation (one of 68), nonnegotiable outflow occlusion (one of 68), delayed bleeding (one of 68), and balloon bursting and shearing becoming occlusive within the graft (one of 68). Primary and secondary patency rates were 72% and 87% at 30 days, 57% and 80% at 90 days, and 44% and 72% at 180 days, respectively. Arterial emboli (two of 68) were treated by Fogarty balloon retrieval and alteplase infusion locally over the course of 20 minutes. One of two PTA perforations was controlled by balloon tamponade. CONCLUSION: Alteplase can be used successfully for hemodialysis graft thrombolysis.

Hepatofugal flow in the portal venous system: pathophysiology, imaging findings, and diagnostic pitfalls.

Hepatofugal flow (ie, flow directed away from the liver) is abnormal in any segment of the portal venous system and is more common than previously believed. Hepatofugal flow can be demonstrated at angiography, Doppler ultrasonography (US), magnetic resonance imaging, and computed tomography (CT). The current understanding of hepatofugal flow recognizes the role of the hepatic artery and the complementary phenomena of arterioportal and portosystemic venovenous shunting. Detection of hepatofugal flow is clinically important for diagnosis of portal hypertension, for determination of portosystemic shunt patency and overall prognosis in patients with cirrhosis, as a potential pitfall at invasive arteriography performed to evaluate the patency of the portal vein, and as a contraindication to specialized imaging procedures (ie, transarterial hepatic chemoembolization and CT during arterial portography). Hepatofugal flow is generally diagnosed at Doppler US without much difficulty, but radiologists should beware of pitfalls that can impede correct determination of flow direction in the portal venous system.