Morphological classification of Renal Disease Using 99mTc-DMSA Scintigram

99mTc-DMSA renal scan has been evaluated not only the renal functional cell mass but also some anatomical structures at a loss of the renal parenchymal function. The author classified a renal morphology of the posterior image of 99mTc-DMSA renal scan as the groups of symmetic and asymmetric morphology, the groups of the large, normal and small sized kidneys, the groups of the central photon defects (PD) which could be noted in a dilated pelvocalyceal system due to obstructive uropathy and the cortical photon defects (CD) due to focal parenchymal lesions or scars after a loss of function and the last groups of the single and multiple CD for a suggestion of the clinical usefulness. Regarding to measurement of norrnal renal size, the longest size of the kidneys were evaluated with 5 cm of a lead scale on the posterior renal image, and those were decided to the limits beteen 104.1 and 119. 4 mm as comparison with the renal size of intravenous pyelogram (IVP) in 59 cases who were underwent 99mTc-DMSA and IVP concommitantly. Among 85 cases of PD in 99mTc-DMSA renal scan, the 61 (71.8%) were cases of a dilated pelvocalyceal system related with obstructive uropathy, meanwhile the 28 (27.0%) of 162 cases with CD were cases of obstructive and infectious uropathy. The probability of a presence of some uropathy in cases of CD were 99.3%, meanwhile that of the presence of CD in cases of some uropathy were 37.9%. Besides, there were some specific anatomical findings such as polycystic kidneys with symmetric enlarged kidneys with multiple CD and the kidneys of chronic renal failure and/or hypertension with syrnmetric small size in 99mTc-DMSA renal scan.