Cholescintigraphy in neonatal jaundice using Tc-99m p-butyl IDA

Congenital biliary atresia (BA) is fatal but surgically treatable when diagnosed within 60 days after birth. To evaluate the value of cholescintigraphy in the early diagnosis of BA, 14 babies with neonatal jaundice, ranging in age from 17 to 126 days, underwent cholescintigraphic examinations using Tc-99m N-(p-butylphenylcarbamoyl-methyl) iminodiacetic acid. Cholescintigrams were interpreted as positive or negative for intestinal RI clearance by two independent radiologists. The intensity of pulmonary radioactivity was compared with cardiac-blood-pool radioactivity on a scale of 1 - 4, and expressed as hepatocyte clearance index. Interobserver variations were not observed. Biliary and intestinal clearance was negative in all 7 patients with surgically proven BA. Among 7 others with neonatal hepatitis, intestinal clearance was positive in three, and negative in the other four. The sensitivity, specificity, and accuracy of cholescintigraphy in diagnosing BA were 100 %, 43 %, and 71 %, respectively. Mean hepatic clearance index, examined on 13 scintigrams, was higher in patients with BA than those with neonatal hepatitis (3.3 vs 2.6). (Namekawa, K.)