Clinical ictal patterns in epileptic patients with occipital electroencephalographic foci.

Seizure patterns and other clinical features were analyzed in 55 epileptic patients with electrographic evidence of exclusive or predominant occipital involvement. Few statistically significant differences in clinical or ictal patterns were found between subjects with purely focal occipital involvement and those with temporal and temporo-parietal spread or minor additional independent foci. On the other hand, cases with bilateral synchronous occipital spike activity appeared to reflect a different type of epileptic disorder. Clinical pleomorphism was more apparent than is commonly conceived; thus, although the incidence of visual auras was relatively high (47 percent), epigastric, psychic, somatic, and other sensory phenomena were not infrequently encountered. Ictal motor patterns were most commonly (53 percent) nonfocal or absent, but partial or focal motor attacks and psychomotor seizures were amply represented. Ictal features with their localizing and lateralizing reliability were also analyzed and discussed in relation to those found in a comparison study of seizures of fronto-centro-parietal origin.