Complex partial epilepsy: the role of neuroimaging in localizing a seizure focus for surgical intervention.

and symmetric. Sensation was intact. Gait and station were normal. Her preliminary studiessuggestedright temporal lobe seizureorigin but werenot definitive. Video-EEG mon itoringwithscalpandsphenoidal (basaltemporallobe) electrodes demonstrated right sphenoidal spike dis chargesonly when asleep.Four seizureswererecorded; one was not localized in origin and three displayed early right temporal lobe activity. A thiopental activation test was negative. Neuropsychometric studies disclosed mild impairment of both verbal and visuo-spatial (including facial recognition) memory. Intracarotid amobarbital injection demonstratedleft hemispheredominance for language and intact memory in the left hemisphere. Because of the inconclusive preliminary testing, fur ther diagnostic procedures were performed to establish a firm diagnosis. A positron emission tomography (PET) scan using fluorine-l8-fluorodeoxyglucose (FDG) was performed to determine regional cerebral metabolism. This showed a significant reduction in the metabolic activity in the right temporal region and ipsilateral thalamus(Fig. 1).Intracranial electrodes were placed bilaterally in the temporal lobes and frontal lobes and the EEG was recorded to determine the source of her seizures. During her 19-day intensive monitoring session, five complex partial seizures and one second arily generalized seizure were observed. All began in the right hippocampus and amygdala. The patient underwent a right anterior temporal lobectomy shortly thereafter without complication. His topathologic examination of the specimen showed me sial temporal sclerosis, with gliosis and cell loss in limbic structures. In the 6 mo since surgery, she has not experienced any auras or seizures, and reports a signif icant improvement in her mood and work performance. Postoperativeneuropsychometric testingrevealedim provement in facial recognition and visual scanning, and no change in verbal memory or language. J NucIMed 1990;31: 1839-1843