Hepatobiliary scintigraphy in the diagnosis of biliary atresia--a Singapore experience.

In recent years, 99mTechnetium IDA hepatobiliary scintigraphy has been widely accepted as a highly sensitive and fairly accurate test in the diagnosis of biliary atresia and evaluation of neonatal jaundice. Over a period of 4 years from 1982 to 1986, a total of 110 paediatric patients had undergone 99mTechnetium IDA hepatobiliary scans in our department for prolonged neonatal jaundice. Their scans were reviewed to evaluate the role of this nuclear imaging technique in the diagnosis of biliary atresia. There were 43 true positive and 49 true negative scans. No false negative scan was encountered in our study. Hence the sensitivity was 100%. However, out of the 110 scans, there was misdiagnosis of biliary atresia in 18 cases. This gave a specificity of 73% with an accuracy of 84%. From this study we concluded that 99mTechnetium IDA imaging is a highly sensitive test in the screening of biliary atresia. However, its specificity is possibly limited by the short half life of the radioisotope 99mtechnetium in delayed 24 hr imaging and we feel that this could be improved by using slightly higher doses than what we are presently using.