Off-site determinations of effective renal plasma flow using technetium-99m-MAG3 and single blood sampling.

UNLABELLED: This study evaluated the feasibility of determining effective renal plasma flow (ERPF) at an off-site central laboratory by transferring blood samples from the on-site laboratory. METHODS: Blood samples were obtained from 66 patients referred for renal imaging with 99mTc-MAG3. ERPF values were determined using the single blood sample method (BSM) at both on- and off-site laboratories. The ERPF values were classified clinically as normal or abnormal. Both the ERPF values and clinical classification were compared between on- and off-site laboratories. RESULTS: The off-site ERPF overestimated those on-site by 2.8% (paired Student's t-test p < 10(-5)). However, off-site ERPF values highly correlated with the values obtained on-site (r = 0.99; p < 10(-5)). In addition, the clinical classification for each patient determined at each site was identical. CONCLUSION: ERPF can be determined accurately off-site. This method should allow many nuclear medicine departments access to the ERPF determination by the BSM at a central off-site laboratory.

The I-131 rose bengal excretion test is not dead.

One hundred and thirty I-131 Rose Bengal Excretion Studies (RBI) were performed on 84 patients over nine years. In 90% (56/60) of cases with biliary atresia, the 72-hour RBI was less than or equal to 7%. In only 12.5% (3/24) of cases with neonatal hepatitis was the 72-hour RBI less than or equal to 7%. The accuracy of the test was 91% with a specificity of 88%. Thirty patients later were studied following a Kasai procedure. The RBI test reliably predicted the patency of the anastomosis. The authors conclude that the 72-hour RBI is a reliable test in the diagnosis of biliary atresia and in the documentation of biliary patency following surgery, provided adequate care is taken in stool collection and measurement.