Reports on the use of I131-labeled rose bengal (RBI131) to help distinguish between the principal causes for jaundice have not been in agreement. Some observers have found the test to be of value,1-12 while others have concluded that it was unreliable13-15 when used for this purpose. Since the methods employed by these investigators were not always the same, the variation in the results obtained may be partially explainable by differences in technique.
In the latter part of 1959, we began a series of studies dealing with hepatic uptake and excretion of RBI131 in experimental animals and man. A modified test16 that ultimately evolved from these studies seemed to hold promise as an aid in the differential diagnosis of jaundice.17 We wish in this communication to present some additional observations and to describe our experience to date with the use of the modified