Chao Long Chen

BACKGROUND: Liver graft size, anatomy of the bile duct and the vascular inflow and outflow are essential for living related liver transplantation (LRLT). Preoperative delineation of those variations that would change the operative procedure to achieve a successful result especially in an emergency condition. PURPOSE: Our aim was to develop a rapid and noninvasive imaging diagnostic method for the detection of anatomical variants that is mandatory for a safe operation when selecting potential liver transplant living donors. We used a different magnetic resonance (MR) imaging technique, which enabled to us to exploit the anatomical landmark of the liver, signal enhancement of blood flow in the abdomen, and the intrahepatic biliary routes inside the liver. Then, with the help of Advantage Window workstation reconstruction, the reconstructed single vascular or biliary systems were displaced in a three-dimensional fashion and the whole examination finished within 30 min. METHODS: Modification of the standard MR technique was performed on a superconductive 1.5T whole body image scanner, MR arteriogaphy, venography, and cholangiography with three-dimensional reconstruction in evaluating the anatomy of the hepatic arteries, hepatic veins, portal venous system, bile ducts, and liver size in potential liver transplant living donors. These anatomical structures were compared with traditional imaging methods. RESULTS: In all 38 cases, as well as delineation of the portal vein detail to the segmental level was satisfactorily obtained in this MR study. The images were well displayed in a three-dimensional fashion, which had good correlation with images from traditional imaging modalities and operative findings. In 86.8% cases, the MR arteriography was well matched with the celiac angiography. Of those 17 operative cases, estimation of liver volume was well correlated with the liver graft within 3.9-12.5% variation. In the major hepatic vein, we obtained 100% accuracy and 88.2% in the minor branches. Of 12 donors received intraoperative cholangiography during liver donation, good correlation of biliary anatomy was achieved. One donor was excluded from graft donation due to the complicated arterial supply to the left liver. According to the anatomical variation, surgical procedures in graft harvesting and anastomosis were readjusted and no major complications were found in those donors and all recipients survived after liver transplantation. CONCLUSION: MR volumetry, venography, angiography, and cholangiography with three-dimensional reconstruction is sufficient for all major imaging evaluation. It may replace the traditional conventional catheter angiography, computed tomography, sonography and endoscopic retrograde cholangiography as a single investigation in the evaluation of the potential liver transplant donors. Angiography is only valuable in suboptimal cases and intraoperative cholangiography is only performed in biliary ductile variants.

BACKGROUND/AIMS: To report the results of surgical treatment of intrahepatic cholangiocarcinoma with different procedures and to find the factors that may affect the long-term survival. MATERIALS AND METHODS: From 1987 to 1994, 57 patients with intrahepatic cholangiocarcinoma underwent laparotomy. Among them, resection was performed in 27 patients, operative drainage in 14 patients and biopsy only in 14 patients. The liver resections included 9 right lobectomies, 14 left lobectomies and 4 hilar resections. All specimens were stained with carcinoembryonic antigen (CEA) and HLA-DR monoclonal antibodies. RESULTS: There were 7 postoperative mortalities, one in the resection group (1/27), two in the drainage group (2/14) and 4 in the biopsy group (4/14). Patients undergoing resection survived significantly longer (median, 8 months) (mean, 19 +/- 4 months) than patients undergoing drainage (median, 4 months) (mean, 6 +/- 2 months) and biopsy (median, 2 months) (mean, 3 +/- 1 months) (p < 0.01). After resection, univariate analysis showed that positive hiliar lymphnode was a poor prognostic sign and mucobilia was a good prognostic sign. Age, sex, size of tumors cell differentiation, clear margin, and positive HLA-DR and CEA had no effect on prognosis. CONCLUSION: The results support the surgical resection of intrahepatic cholangiocarcinoma. Tumor free margin should be aggressively achieved but may not be necessary. Mucobilia is a good prognostic sign and positive hilar lymphnode is a grave sign.

AIM: The effect of fatty liver on graft survival, especially with reference to macrovesicular and microvesicular steatosis, is still uncertain. This preliminarily study was designed to create a noninvasive method for the quantification of the hepatic fat content in vivo and to establish provisional criteria for the assessment of fatty donor livers before liver transplantation among transplant surgeons, radiologists, and pathologists. METHODS AND MATERIALS: Different degrees of rat fatty liver model were established by feeding rats a diet deficient in choline and methionine for different periods of time. Computed tomography (CT) with test tubes containing variable percentages of fat equivalent substance were used to assess the severity of fatty change of the rat liver. This was then correlated with the histological classification, level of hepatic enzymes, and graft survival. RESULTS: Linear correlation between the fat volume fraction added to the test tubes and CT density were found. The process of producing a fatty liver via diet alteration peaked at week 3. At this time hepatic enzymes, radiological fat content, and posttransplantation survival were worse (P=0.013), compared with other time points. Radiological assessment of fatty liver correlated well with survival and serum glutamic oxaloacetic transaminase and glutamic pyruvate transaminase levels. CONCLUSION: Severe microvesicular steatosis does not influence recipient survival, however, macrovesicular steatosis affects graft survival. Caliber CT is a practical and simple method that allows an accurate noninvasive quantitative assessment of hepatic fatty infiltration. It has potential to be a useful parameter for the assessment of donor livers for clinical liver transplantation.

The variations in the anatomy of intrahepatic bile ducts complicate operations in living related liver transplantation (LRLT) and therefore preoperative delineation of the biliary system is important to achieve a successful outcome. The aim of this study was to establish a standard relationship between the biliary variations and the methods of the graft splitting and anastomosis. Of 958 endoscopic retrograde cholangiographies with good visualization of bile duct branches were selected and were available for evaluation of their ramifications and variants. According to drainage of right hepatic duct and left hepatic duct, we classified the bile ducts into two major groups. Unusual routes of the intrahepatic ducts were present in 105 cases (11% in group A) the right sectoral duct drained into the left hepatic duct directly; in 200 cases (21% in groups B) the duct of segment IV drained into right side or common hepatic duct; and in 29 cases (3% in groups B) the duct of segment: II and III drained into the CBD and right hepatic duct separately. There is no specific bile duct variation that forbids someone from LRLT and SLT, but unusual intrahepatic ducts routes may require a change both in the cutting plane during graft retrieval and pattern of ductoenteral anastomosis to avoid potential complications to both donors and recipients. Cholangiography for screening intrahepatic duct variations is therefore important for safe bile drainage for both donors and recipients.

Pathologic changes of the recipient native portal venous system may cause thrombosis of the portal vein, especially in pediatric living donor liver transplantation (LDLT). This study assessed the utility of Doppler ultrasound (US) for the detection of intraoperative portal vein occlusion and identification of predisposing risk factors in the recipients. Seventy-three pediatric recipients who underwent LDLT at Chang Gung Memorial Hospital, Taiwan, from 1994 to 2002 were included. Preoperative and intraoperative Doppler US evaluation of the portal vein was performed. Age, body weight, native liver disease, type of graft, graft recipient weight ratio (GRWR), type of portal anastomosis, portal velocity, portal venous size and presence of portosystemic shunt were analyzed for statistical significance of predisposing risk factors. Eight episodes of intraoperative portal vein thrombosis, with typical findings of absent Doppler flow in portal vein and prominent hepatic artery with a resistant index lower than 0.5 (p < 0.001), were detected during transplantation, which was then corrected by thrombectomy and re-anastomosis. Children age < or =1 yr (p = 0.025), weight < or =10 kg (p = 0.024), low portal flow < or =7 cm/s (p = 0.021), portal venous size < or =4 mm (p = 0.001), and GRWR >3 (p < 0.017) were all risk factors for intraoperative portal vein thrombosis. Doppler US is essential in the preoperative evaluation, early detection and monitoring of outcome of the portal vein in liver transplant.