Pathologic significance of low-attenuation hepatic parenchymal abnormalities in CT scans of living related donor partial liver transplant recipients.

PURPOSE: To evaluate the pathologic significance of the low-attenuation changes of liver grafts in living donor partial liver transplantation (LDLT) on computed tomography (CT). MATERIALS AND METHODS: We retrospectively correlated the low-attenuation changes of liver grafts which were defined as readings below 50 HU on unenhanced CT with histological findings obtained by needle biopsy or surgery within seven days of CT studies. The study group included 35 CT findings of 35 recipients. We classified the low-attenuation change of the liver grafts into a homogeneous low-attenuation group and a heterogeneous low-attenuation group. RESULTS: Major histologic findings of 35 specimens included cholangitis in 10 (28.6%), cholestasis in eight (22.9%), fatty change in 15 (42.9%), acute cellular rejection (ACR) in 12 (34.3%), acute hepatitis in three (8.6%), liver cell ballooning in four (11.4%), massive hepatic necrosis in four (11.4%), and centrilobular congestion in five (14.3%) cases, respectively. Homogeneous and heterogeneous low-attenuation changes of liver grafts on unenhanced CT were seen in 26 (74.3%) and 9 (25.7%) cases, respectively. Massive hepatic necrosis occurred more frequently among the heterogeneous low-attenuation group than among the homogeneous low-attenuation group. CONCLUSION: Low-attenuation changes in liver grafts on CT may indicate a variety of pathological changes. Heterogeneous low-attenuation changes suggest massive hepatic necrosis.

Transcatheter arterial embolization for bleeding from bile duct tumor thrombi of hepatocellular carcinoma.

BACKGROUND/AIMS: Advanced hepatocellular carcinoma usually invades the portal vein, forming tumor thrombi. Invasion of the bile duct, i.e., intrabile tumor growth or bile duct tumor thrombi is rare. Patients with bile duct tumor thrombi present with obstructive jaundice, abdominal pain or hemobilia. Hemobilia due to bile duct tumor thrombi is sometimes massive and fatal. The purpose of our study was to evaluate the effectiveness of transcatheter arterial embolization for hemobilia caused by bile duct tumor thrombi of hepatocellular carcinoma. METHODOLOGY: Between 1993 January and 2000 December, transcatheter arterial embolization was performed in 4 patients with hemobilia and gastrointestinal bleeding from bile duct tumor thrombi of hepatocellular carcinoma. RESULTS: In all 4 patients, transcatheter arterial embolization was successfully performed and resulted in cessation of bleeding. One patient had recurrent hemobilia, which was controlled by another transcatheter arterial embolization. Three patients were discharged from hospital after transcatheter arterial embolization. Patients died of hepatic failure or multiple tumors 5 to 7 months after the onset of hemobilia, although hemobilia had been fully controlled. CONCLUSIONS: Transcatheter arterial embolization seemed to be effective for the control of massive hemobilia caused by bile duct tumor thrombi associated with hepatocellular carcinoma.

Factors influencing liver regeneration following living-donor liver transplantation of the right hepatic lobe.

BACKGROUND: As a result of the shortage of cadaveric livers for adults, many institutes perform living-donor liver transplantation (LDLT) using right-lobe grafts. It is important to learn whether regeneration of the graft is compromised by division of middle hepatic vein (MHV) tributaries. Accordingly, we studied the effect on graft regeneration of transection of the MHV tributaries and other factors, including graft versus body weight ratio (GRBW). METHODS: Of 100 adult recipients having undergone right-lobe LDLT, 30 6-month survivors were studied. Liver regeneration was assessed by volumetry based on the computed tomography (CT). A regeneration index was defined as the ratio of the graft volume 6 months after LDLT to the preoperative value. The dominance of the MHV tributaries over the right hepatic vein in venous drainage of the anterior segment was evaluated by preoperative CT using a 5-point scale. RESULTS: The regeneration index of the posterior segment was significantly greater than that of the anterior segment (Wilcoxon signed rank test, P=0.01). The relatively poor regeneration of the anterior segment compared with the whole graft was associated with preoperatively dominant MHV tributaries (Spearman rank correlation: R=-0.44, P=0.01). The only significant determinant of the whole-graft regeneration, however, was GRBW (stepwise regression: Y=-0.80X+0.2, R(2)=0.70, P<0.0001). CONCLUSIONS: Despite deprivation of MHV tributaries, a graft will regenerate to meet the metabolic demand, and a smaller graft for the recipient is capable of regenerating to a greater extent.

Efficacy of nonsurgical treatments for hepatocellular carcinoma in the caudate lobe.

PURPOSE: To evaluate the efficacy of nonsurgical treatments for caudate hepatocellular carcinoma (HCC). METHODS: Between January 1994 and February 2001, 25 patients were treated for HCCs with percutaneous ethanol injection (PEI), and/or transcatheter arterial embolization (TAE). PEI was performed for 19 caudate HCCs, combined treatment with PEI and TAE for 4 nodules, and TAE for 2 nodules. RESULTS: During follow-up periods ranging from 3 to 60 months (mean 21.3 months), 18 patients had no local recurrence. Local recurrence was seen in 7 patients, and recurrence in the other segments of the liver in 15 patients. Thirteen patients were alive, ranging from 6 to 60 months, and 12 patients died of multiple HCCs, hepatic failure, or rupture of esophageal varix. The 1-, 2-, 3-, and 5-year survival rates of the 25 patients were 70.6%, 60.2%, 48.1%, and 16.0%, respectively. CONCLUSION: PEI, PEI and TAE, or TAE would be an effective alternative treatment for HCC in the caudate lobe.

Small hepatocellular carcinoma: comparison of radio-frequency ablation and percutaneous microwave coagulation therapy.

PURPOSE: To evaluate the effectiveness of radio-frequency (RF) ablation and percutaneous microwave coagulation (PMC) for treatment of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Seventy-two patients with 94 HCC nodules were randomly assigned to RF ablation and PMC groups. Thirty-six patients with 48 nodules were treated with RF ablation, and 36 patients with 46 nodules were treated with PMC. Therapeutic effect, residual foci of untreated disease, and complications of RF ablation and PMC were prospectively evaluated with statistical analyses. RESULTS: The number of treatment sessions per nodule was significantly lower in the RF ablation group than in the PMC group (1.1 vs 2.4; P <.001). Complete therapeutic effect was achieved in 46 (96%) of 48 nodules treated with RF ablation and in 41 (89%) of 46 nodules treated with PMC (P =.26). Major complications occurred in one patient treated with RF ablation and in four patients treated with PMC (P =.36). During follow-up (range, 6-27 months), residual foci of untreated disease were seen in four of 48 nodules treated with RF ablation and in eight of 46 nodules treated with PMC. No significant difference in rates of residual foci of untreated disease was noted (P =.20, log-rank test). CONCLUSION: RF ablation and PMC thus far have had equivalent therapeutic effects, complication rates, and rates of residual foci of untreated disease. However, RF tumor ablation can be achieved with fewer sessions.

Transcatheter microcoil embolotherapy for ruptured pseudoaneurysm following pancreatic and biliary surgery.

PURPOSE: To evaluate the outcome of transcatheter microcoil embolotherapy for bleeding pseudoaneurysms complicating major pancreatic and biliary surgery. MATERIALS AND METHODS: Over an 8-year period, 8 patients were encountered who developed massive bleeding from pseudoaneurysms 15-64 days (mean 31 days) following major pancreatic and biliary surgery. Urgent transcatheter microcoil embolotherapy was performed in all 8 patients. RESULTS: Transcatheter embolotherapy was successful in 7 of 8 patients (88%) but failed in one due to development of disseminated intravascular coagulation. One patient developed recurrent bleeding 36 days after the first embolotherapy from a newly developed pseudoaneurysm, which was again treated successfully with embolization. Two patients subsequently underwent additional surgery for residual pathology. Three of the 7 patients with successful embolotherapy were alive at 10-96 months, 4 patients died of associated malignancies 4-20 months after embolotherapy. CONCLUSION: Transcatheter microcoil embolotherapy is effective for bleeding pseudoaneurysms complicating pancreatic and biliary surgery, and should be considered the first treatment of choice.

CT-guided transthoracic percutaneous ethanol injection for hepatocellular carcinoma not detectable with US.

PURPOSE: To evaluate the safety and effectiveness of computed tomography (CT)-guided percutaneous ethanol injection (PEI) for the treatment of hepatocellular carcinoma (HCC) not detectable with ultrasonography (US). MATERIALS AND METHODS: Between April 1994 and January 2001, 51 patients with 57 HCC nodules not detectable with US underwent CT-guided transthoracic PEI. Complications associated with the transthoracic approach, effectiveness of transthoracic PEI, and prognosis of the patients were evaluated. RESULTS: Seventy-one PEI sessions were performed for 57 nodules. Complications included pneumothorax in 21 sessions (30%) for 19 nodules (33%), moderate pleural effusion in four sessions (6%) for four nodules (7%), and hemoptysis in three sessions (4%) for two nodules (4%). A chest tube was required for pneumothorax in five sessions (7%) for five nodules (9%), and pleural effusion drainage was performed in two sessions (3%) for two nodules (4%). Apparent tumor necrosis was noted at CT in 51 nodules (89%). During follow-up (range, 3 months to 5(1/2) years; mean, 29 months +/- 18 [SD]), local recurrence was seen in seven nodules (12%), three of which received repeat treatment with transthoracic PEI. Twenty-six patients survived, and 25 patients died of multiple tumors, hepatic failure, or rupture of esophageal varices. CONCLUSION: Transthoracic PEI seems to be relatively safe and effective for the treatment of HCC not detectable with US.

Benign hepatic nodules in Budd-Chiari syndrome: radiologic-pathologic correlation with emphasis on the central scar.

OBJECTIVE: The purpose of this study was to determine the imaging features of benign hepatic nodules in patients with Budd-Chiari syndrome and to correlate them with pathologic findings, with special attention placed on the presence of a central scar. MATERIALS AND METHODS: Imaging findings of 59 benign hepatic nodules in four patients with chronic Budd-Chiari syndrome were analyzed retrospectively, and radiologic- pathologic correlation was performed in three patients with 50 hepatic nodules who underwent liver transplantation. All patients underwent multiphasic helical CT. In three patients with 29 lesions, MR imaging, including a multiphasic dynamic study, was performed. The CT and MR imaging findings in these patients were compared with those of 103 small hepatocellular carcinomas in 56 other patients (54 of them displayed chronic hepatitis or liver cirrhosis associated with viral hepatitis but none had Budd-Chiari syndrome). Image analysis was performed by two radiologists with no knowledge of the diagnosis. RESULTS: All patients with Budd-Chiari syndrome exhibited multiple benign nodules up to 3 cm in diameter, and 42 of 59 lesions were hypervascular. Microscopically, 15 of 32 nodules demonstrated a central scar; moreover, some nodules closely resembled focal nodular hyperplasia. Frequencies of hyperintensity on T1-weighted images (14/29 vs 25/103), hypointensity on T2-weighted images (7/29 vs 1/103), and the presence of a central scar (6/59 vs 1/103) were significantly higher in benign nodules than in hepatocellular carcinomas (p < 0.05; Fisher's exact test). Moreover, for lesions larger than 1 cm, imaging studies revealed a central scar in six of 15 benign lesions. CONCLUSION: Benign hepatic nodules in patients with in Budd-Chiari syndrome are usually small, multiple, and hypervascular. The presence of a central scar is a characteristic feature in those larger than 1 cm in diameter.