Renal Technetium-99m-DMSA SPECT in Normal Volunteers

Dimercaptosuccinic acid (DMSA) renal scintigraphy today is considered a sensitive and useful technique for the detection of cortical abnormalities. Recent studies have suggested that lesion detection can be improved by SPECT imaging. This study investigated normal kidneys using different SPECT modalities. Ten young, healthy volunteers with normal clinical history and normal renal ultrasound underwent planar and SPECT DMSA imaging 2 to 4 hr after intravenous injection of 99mTc-DMSA (185 MBq). Analysis of SPECT data was focused on the homogeneity of cortical uptake (comparison of upper and lower pole activity) as well as on the presence or absence of focal cortical defects. No abnormality could be observed on the planar images. SPECT revealed, in seven kidneys (five left and two right), the presence of a hypoactive upper pole. This was visually observed on the coronal slices with up to 35% difference between upper and lower pole. Moreover, three focal cortical defects were visualized on the coronal slices as well as on three-dimensional surface shade displays. These normal patterns should be recognized when evaluating a patient with possible renal involvement.