Introduction: Recently, multidetector computed tomography (MDCT) has been introduced into clinical practice. MDCT has become the noninvasive diagnostic test of choice for detailed evaluation of biliary obstruction. Aim: the main objective of the present study was to evaluate the diagnostic value of MDCT compared to invasive procedures for detecting biliary obstruction causes. Material and Methods: Since February 2009 until May 2011 fifty biliary obstruction patients based on clinical, laboratory or ultrasonographic findings, were evaluated by Multidetector-row computed tomography. The causes of biliary obstruction, which was identified using MDCT were classified into three categories: calculus, benign stricture, and malignancy. Final diagnosis was conducted based on percutaneous transhepatic cholangiography (PTC), endoscopic retrograde cholangiopancreatography, biopsy, or surgery. The MDCT diagnosis and were compared with the final diagnosis. Results: A correct diagnosis of causes of biliaryobstruction was made on the basis of MDCT findings for 44 of the total 50 patients. Two patients with chronic pancreatitis were incorrectly diagnosed with a pancreatic head adenocarcinoma on the basis of MDCT findings. One patient with biliary stone was incorrectly diagnosed with a periampullary adenocarcinoma on the basis of MDCT findings. The Sensitivity, specificity and accuracy of MDCT in the diagnosis of causes of biliary obstruction were 94.12% and87.87% and94.6% respectively. Conclusion: Based on the findings of this study MDCT has an excellent image quality, providing valuable information about the biliary tree and other abdominal organs. The use of advanced image processing, including maximum intensity projection and multiplanar reconstruction (especially coronal or sagittal reformatted images), allows superior visualization of the biliary tree and vascular structures. Three-dimensional reconstruction images complement axial images by providing a more anatomically meaningful display of the lesion and its relationship to adjacent structures, and accurate determining the craniocaudal extent of the lesion. High accuracy, wide availability and ease of use, make the MDCT the imaging modality of choice for evaluation of biliary obstruction.
Key words: Biliary obstruction, Diagnosis, Multidetector-row computed tomography, Accuracy, Sensitivity.