Regional brain perfusion changes in patients with primary generalized epilepsy assessed by Tc99m HM-PAO and SPECT.

Cerebral distribution of Tc99m-hexamethylprolenaminoxim (HMPAO) was investigated using single photon emission computerized tomography (SPECT) in 34 patients with primary generalized epilepsy (PGE) during the interictal state. These findings were compared with those in a control group of 9 healthy volunteers. In control subjects uniform selective uptake of HMPAO in cortex, basal ganglia and thalamus was found. In 30 patients (88%) decreased regional perfusion was found as follows: in the cortical region in 6 patients (18%), in the region of the basal ganglia or thalamus in 7 (20%), and in both regions in 17 patients (50%). Four patients had normal SPECT findings. The obtained results permit a hypothesis that the PGE should not be strictly differentiated from the focal epilepsy. A possible explanation of the pathophysiology of PGE has also been discussed.