MRCP VERSUS ERCP IN THE DETECTION OF CHOLEDOCHOLITHIASIS IN PATIENTS WITH OBSTRUCTIVE JAUNDICE

gallstones are a common clinical problem prevalent all around the world.choledocholithiasis is an important associated problem with known serious complications such as obstructive jaundice, pancreatitis and cholangitis. [1]recently there has been a rapid evolution in the modalities available to evaluate for choledocholithiasis. commonly used diagnostic modalities include ultrasonography [usg], computed tomography [ct], endoscopic retrograde cholangiopancreatography [ercp], percutaneous transhepatic cholangiography [ptc] and magnetic resonance rholangiopancreatography [mrcp]. [2] endoscopic retrograde cholangiopancreatography [ercp] is considered the 'gold standard' for the diagnosis of biliary obstruction and is among the several invasive techniques involving direct cholangiography with additional benefit of a higher spatial resolution. it is operator dependent and has an overall reported morbidity of up to 5 % and mortality of 0-1%.magnetic resonance cholangiopancreatography [mrcp] is a non-invasive alternative to diagnostic ercp for investigating biliary obstruction without any associated morbidity and mortality. [3]since the most common cause of biliary obstruction is choledocholithiasis the purpose of this study was to determine the sensitivity, specificity, accuracy, negative and positive predictive values of mrcp using 3 tesla mri systems in detecting choledocholithiasis compared to ercp.objective of the study: to determine the diagnostic accuracy of magnetic resonance cholangiopancreatography using 3 tesla mri systems for detection of choledocholithiasis in patients with obstructive jaundice using ercp as gold standard.study design: cross-sectional study.study setting: department of radiology.duration of study: a minimum of 6 months after the approval of study.subjects: all the adult patients of either gender aged 15 years to 65 years presenting with obstructive jaundice and subsequently referred by their primary treating physician to the radiology department for mrcp examination were included in this study. patients with contraindication to mrcp or those who did not undergo ercp or those who presented with obstructive jaundice due to causes other than biliary stones were excluded from the study.methods: mrcp will be performed using toshiba 3t mri system [toshiba medical systems, japan]. heavily t2 weighted axial sections with 3d reconstruction and maximum intensity images will be acquired. the mrcp and ercp examinations will be interpreted for the presence of choledocholethiasis by consultant radiologists, having at least 5 years of experience in mri imaging, in a blinded fashion. moreover, to further eliminate any possible bias, no clinical indication will be provided to the consultant radiologist.results: of the 153 subjects included in this study 87 were females and 66 were males. the mean age of subjects included in the study was 45 years with standard deviation 13.7 years. the age range was from 15 years to 65 years. mrcp correctly diagnosed choledocholithiasis in 146 of the 153 patients, there were 146 true positive cases and 1 false positive case. there were 1 false negative and 5 true negative cases. the sensitivity of mrcp was found to be 99.3% and specificity was 83.3%. positive predictive value of mrcp was 99.3% while the negative predictive value was found to be 83.3 %. the diagnostic accuracy of mrcp for choledocholithiasis was found to be 98.6%.conclusion: technical advances in the techniques of mrcp over the past two and a half decades both in terms of primary imaging and post processing are significant. this has made mrcp the radiological investigation of choice for diagnosis of biliary disorders including choledocholithiasis. this study further validates the imaging role of mrcp as a test fit for purpose and acknowledges that increased magnetic field strength of 3t mri system has a superior diagnostic yield. Keywords: Choledocholithiasis, Magnetic Resonance Cholangiopancreatography, Endoscopic retrograde cholangiopancreatography, Jaundice, Ultrasonography