[Quantitative analysis in nuclear nephrourology: clearance, uptake and transit time].
Radionuclide renal study is only a method that can provide anatomical as well as functional information on the kidney. There have been many reports on quantification of the renal function using radionuclides. They are summarized to two groups: blood and/or urine sampling method and external counting method. The former is accurate and reproducible in quantification of the renal function, but is rarely applicable in a routine practice due to technical complexity. On the contrary, the external counting method by means of a gamma camera and dedicated computer system is simple and practical in a routine use, but is less in reliability of quantitated renal function than sampling method. In this paper, technical and diagnostic characteristics of the quantitative methods on renal function using the radionuclide are reviewed.