The aim of this study was to evaluate the brain scintiscan images with (123)I-ioflupane for the diagnosis of patients with early Parkinson's disease (PD). Sixteen patients were studied, nine males and seven females, aged between 38-81 y (mean age: 64 y). All patients underwent thyroid blocking by oral administration of 120 mg potassium iodide before and 24 h after the intravenous (iv) injection of 110-185 MBq/70 kg patient's weight, of (123)I-ioflupane. To check the correct biodistribution of the radiopharmaceutical, whole-body scans were performed at 15 min and 2-3 h after the administration of the radiopharmaceutical. All patients underwent brain single photon emission tomography (SPET) scans on a SPET gamma-camera 3-5 h after (123)I-ioflupane administration. To compensate for scatter and to avoid artifacts, the filtering and reconstructing procedures of the images were performed individually for each patient. Brain SPET results were evaluated semi-quantitatively using different indices. The morphology of the nigrostriatum (NS) area was also examined visually. The (123)I-ioflupane uptake by the affected nigrostriatum (ANS) was compared to a similar area at the occipital (Occ) brain section and to a similar area at the opposite NS. When the value of ANS/Occ was within the confidence limit of 1.507-1.636 and the value of ANS/NNS was within the limit of 0.755-0.889, PD was diagnosed (P<0.05). Thirteen of our patients were diagnosed as having PD and were given l-DOPA treatment. In the remaining patients the diagnosis of PD was rejected due to normal scintigraphic and morphologic findings of the NS area. The interest of this article lies in the following: The correct distribution of the radiopharmaceutical was confirmed by whole body scintiscan. Parameters for better quality of imaging were individually selected for each patient. The morphology of the NS areas, as estimated visually by us, was in accord with the scintigraphic (123)I-ioflupane uptake. The diagnosis of PD was clinically confirmed after treatment with l-DOPA in a seven month follow up period. Results from the small number of cases studied showed: 93% sensitivity and maximum specificity for the diagnosis of PD.