[en] Fifteen patients with cerebral tumours (CTU) and 36 patients with cerebrovascular disease (CVD) were subjected to nuclear medical examinations using ¹²³I-amphetamine (IMP). The results of planar scintigraphy were evaluated in comparison to those obtained with the Single Photon Emission Computerized Tomography (SPECT)-technique, which, in turn, were compared with those of Transmission Computerized Tomography (TCT). In addition, the phenomenon of diaschisis cerebellaris was studied in patients with a primary lesion in the precentral contralateral cortex. SPECT clearly proved superior to planar scintigraphy in detecting both cerebral tumours and cerebrovascular lesions. According to the results obtained in our group of patients with cerebral tumours, ¹²³I-IMP-SPECT offers no major diagnostic advantages in comparison to TCT. In patients with CVD, IMP-SPECT proved superior to TCT with regard to both detection of cerebral tumours and localization of areas affected by transitory ischaemia. Similar advantages of IMP-SPECT were also found in the diagnosis and localization of cerebral insults. Positive diaschisis cerebellaris was able to be detected in 5 out of 8 CTU-patients, and in 16 out of 17 CVD-patients. ¹²³I-IMP, as a metabolically active substance, seems to be particularly suited for diagnosis of cerebrovascular disease. These tests should, however, always be carried out with the SPECT technique. (orig.)