[Usefulness of radioisotope (RI) deconvolution analysis with Tc-99m-DTPA in transplanted kidney]

In 50 renal transplant recipients, we performed radioisotope (RI) deconvolution analysis, as reported by O'Reilly, in 179 renograms from dynamic renal scanning with Tc-99m-DTPA and obtained MTT (mean transit time) and H0 (initial height) values. We found characteristic features of various graft conditions using the combination of MTT and H0. The mean H0 value was greater in normally functioning grafted kidneys than in kidneys with other states. The mean MTT in the normal group was about 2 min. In the acute rejection group, the mean H0 value was lower and the mean MTT was more prolonged compared with the normal group. In ATN group, the mean MTT was similar to that in the acute rejection group, whereas the mean H0 value was lower. In the chronic rejection group, the mean MTT was similar to that in the normal group, but the mean H0 value showed a lower one. The hydronephrosis group had an extremely prolonged MTT. This study indicated that the combination of H0 and MTT obtained from RI deconvolution analysis is a valuable means of understanding the condition of renal grafts.