Comparison of MRCP with Intraoperative Cholangiography in Paediatric Choledochal Cyst and Biliary Atresia

Abstract

Background: Hepatobiliary and pancreatic disorders in children are infrequent and include Duct union (APBD -union), Extra hepatic biliary atresia (EHBA), Caroli's disease, primary sclerosing cholangitis, pancreas divisum and pancreatic duct abnormalities. A range of investigations have been used for evaluation of these disorders in children ranging from sonography, HIDA Scan computed tomography, ERCP, Cholangiography and MRCP. Among these MRCP is a non-invasive investigation which has the potential to delineate the hepatobiliary pancreatic ductal system pre-operatively to help surgeon in diagnosis and operative planning Aims and objectives: The purpose of this study was to determine whether MRCP is feasible in paediatric age group patients and to look for the possible measures to optimize the pediatric MRI. Furthermore, we calculated sensitivity, specificity and accuracy of this test by comparing the results of this test with those of surgery and intra-operative cholangiogram (IOC). Material and Methods: This study was a prospective and descriptive study between Oct -2012 to Jan-2015. We examined 50 consecutive children (28 boys and 22 girls), who were suspected of having pancreaticobiliary disease. Besides base line sonography, MRCP was performed in all patients. The findings of MRCP were compared with those of intraoperative cholangiography (IOC). HIDA was done in 20 patients with neonatal cholestsis and these results were also compared with IOC. Results: A total of 50 children (7 neonates, 17 infants and 26 older children), 30 children with ductal dilatation and 20 children with cholestatic jaundice. The sensitivity, specificity and accuracy of MRCP were 50%, 75% and 60% respectively in detecting the APBD-union in our series. The sensitivity, specificity, accuracy, Positive predictive value and Negative predictive value of MRCP were 84.61%, 85.71% and 85%, 91.66% and 75% respectively in detecting biliary atresia. For patients with neonatal cholestasis, biliary atresia was excluded if there was visualization of normal extra-hepatic biliary system at MR cholangiography. The sensitivity ,specificity ,positive predictive valve ,negative predictive valve and accuracy of 99mTc-HIDA was 69.23%, 71.42%, 81.8%, 61.1% and 70% respectively. Sedation was required in patients in infants in 10 instances for an optimal MRCP in children. Out of 24 patients having age <1 year, oral Trichlorphos @ 50-100 mg/Kg was required in 6 instances and intravenous diazepam was needed in 4 patients. Conclusion: MRCP is effective in delineated choledochal cyst type, and helpful in diagnosing related pancreaticobiliary anomalies, such as APBD–union. But more evaluation needs to be done to assess the MRCP ability to detect APBD –union. Furthermore from our preliminary results, we can conclude that BA can be ruled out if complete extrahepatic bile duct (EHBD) is delineated on MRCP .If EHBD is partially visualized, BA cannot be ruled out because atresia may involve only one part of EHBD. Non – visualization of entire EHBD is suggestive but is not synonymous of BA.