The evaluation of hepatocellular carcinoma with biphasic contrast enhanced helical CT scan.

OBJECTIVE: To evaluate the role of biphasic contrast-enhanced helical CT including Hepatic Arterial Phase (HAP) imaging with Portal Venous Phase (PVP) imaging, in the detection and characterization of hepatocellular carcinomas. METHODS: The study included 40 patients (M = 26, F = 14) with histopathologically proven HCC. Age range was between 30-85 years (mean = 55) by following consecutive patients with cirrhosis in whom Hepatocellular carcinoma was diagnosed or suspected either by raised serum a (alpha)-fetoprotein level or Ultrasound. RESULTS: Biphasic contrast-enhanced examination revealed a total of 85 lesions in these 40 patients, out of which 13 were unifocal, 12 showed a dominant mass with satellite lesions, 2 showed cluster of contiguous nodules and 13 were multifocal HCCs. Mean diameter was 3.1 cm, ranging from 0.8 to 14 cm. On HAP imaging 85% were detected. (hyperattenuating = 69, hypoattenuating = 3) while on PVP imaging detectibility was only 48% (hyperattenuating = 2, hypoattenuating = 39). Hence detectibility was significantly (p = 0.008) superior in HAP as compared to PVP imaging. In 7 patients (17%) tumor was visible only on HAP images. Venous invasion was present in 12 patients (30%) while arterio-portal shunting was seen in 5 patients (13%). CONCLUSION: Biphasic contrast enhanced helical CT is a useful method in detection and characterization of HCC.

The role of magnetic resonance cholangiopancreatography (MRCP) in obstructive jaundice.

OBJECTIVE: To evaluate the diagnostic value of MRCP in studying the sites and cause of obstructive jaundice in comparison with other imaging modalities at the Department of Radiology, Aga Khan University Hospital, from January 1999 to May 2001. METHODS: Forty nine consecutive patients included 19 men and 30 women, suspected of obstructive jaundice. Patients underwent ultrasound (n = 49), CT (n = 11), ERCP (n = 25) and biliary surgery (n = 17). Final diagnosis was established by surgical exploration, endoscopic sphincterectomy, cytology and clinical follow up. RESULTS: Of the 49 patients 17 had choledocholithiasis. Twenty five patients had malignant strictures, out of which 11 had non-specific malignant strictures, 7 had pancreatic carcinoma, 3 had Klatskin tumors, 3 had periampullary carcinoma and 1 had gallbladder carcinoma. Six patients had benign strictures and 1 patient had choledochal cyst. Overall, MRCP was sensitive (88%) and specific (96.8%) in detecting choledocholithiasis. MRCP sensitivity and specificity in detecting benign main bile duct stricture was equal to 83.3% and 97.6% respectively, and 92% and 100% for malignant stricture. CONCLUSION: Our prospective study confirms that MRCP, a noninvasive and well tolerated imaging technique is of value in the diagnosis of obstructive jaundice.