Mielke R, Weber-Luxenburger G, Kessler J, Szelies B, Heiss W D
Max-Planck-Institut für Neurologische Forschung und Universitätsklinik für Neurologie, Köln, Germany.
Epilepsia. 1997 Mar;38(3):370-3. doi: 10.1111/j.1528-1157.1997.tb01130.x.
To study benzodiazepine receptor (BZR) density and functional deficits in occipital lobe epilepsy.
A 39-year-old man who had simple partial visual seizures after neurosurgical transtentorial extirpation of a pinealoma was studied by EEG, magnetic resonance imaging (MRI), and positron emission tomography (PET) of [18F]2-fluoro-2-deoxy-D-glucose (FDG) at rest and during visual activation task and[11C]flumazenil (FMZ).
Electroencephalographic recordings were nonspecific, and MRI did not reveal any morphologic anomaly in the occipital lobe. Flumazenil-PET demonstrated a small epileptogenic region in the right visual association cortex and FDG-PET showed hypometabolism in a corresponding location and thalamic diaschisis. Stimulation of occipital metabolism by a continuous visual recognition task improved significantly the contrast between the dysfunctional zone and its surround.
As BZR deficits are restricted to a small region, widespread hypometabolism in networks involved in visual information processing indicates an extensive functional deactivation by the epileptogenic focus.
