The value of quantitative methods for assessment of renal transplant and comparison with physician expertness

Radionuclide renal diagnostic studies play an important role in assessing renal allograft. Various quantitative parameters have been derived from the Radionuclide renogram to facilitate and confirm the changes in perfusion and/or function of kidney allograft. These quantitative methods were divided into parameters used for assessing renal graft perfusion and parameters used for evaluating parenchymal function. The blood flow in renal transplants can be quantified by measuring the rate of activity appearance in the kidney graft and the ratio of the integral activity under the transplanted kidney and arterial curves e.g. Hilton's perfusion index and Karachi's kidney/aortic ratio. Quantitative evaluation of graft extraction and excretion was assessed by parameters derived from 123I/131I-OH, 99mTc-DTPA or 99mTc-Mag renogram. In this study we review retrospectively renal transplanted patients scintigraphies that all of them under gone to renal allograft needle biopsy nearly to date of allograft scan. We performed quantitative methods for all patients. We observed perfusion parameters affected by quality of bolus injection and numerical aviations related to changes in the site and size of region of interest. Quantitative methods for renal parenchymal functions were nonspecific and far from defining a specific cause of graft dysfunction. In conclusion, neither perfusion nor parenchymal parameters have not enough diagnostic power for specific diagnosis of graft dysfunction. Physician expertness by using scintigraphic images and renogram curves is more sensitive and specific for diagnosis of renal allograft dysfunction