Cerebral blood flow abnormality in patients with idiopathic generalized epilepsy

To investigate the regional cerebral blood flow (rCBF) changes in patients with idiopathic generalized epilepsy (IGE), we compared brain single photon emission computed tomography (SPECT) images of drug naïve IGE patients with those of age/sex matched healthy volunteers.

Brain interictal 99mTc-ethylcysteinate dimer SPECT was performed in 21 patients with IGE (M/F = 10/11, 21.3 +/- 2.7 years) and 21 normal controls. The seizure types were generalized tonic-clonic seizure in 14 patients and myoclonic seizures with rare generalized tonic-clonic seizures in seven. Differences of rCBF between an IGE group and a normal control group were examined by the statistical parametric mapping (SPM) of brain SPECT images using independent t test.

The SPM analysis showed that the rCBF of the IGE patients was significantly reduced in the anterior and posterior cingulate gyri, bilateral anterior nuclei and right dorsolateral nucleus of the thalamus, right superior colliculus of the midbrain, and the cerebellum at the level of uncorrected p < 0.005. In the small volume correction analysis for the thalamus and brainstem, the rCBF was also significantly decreased in the same brain regions at the level of FDR corrected p < 0.05. No brain regions of the IGE patients had increased rCBF.

Our study demonstrates that the interictal rCBF in drug naive IGE patients is reduced in the cingulate gyrus, thalamus, brainstem and cerebellum. This result suggests that dysfunctions in these brain regions are associated with IGE.