Occipital pole area and language dominance.

A previous report demonstrated a relationship between asymmetries of occipital lobe length measured on magnetic resonance images (MRIs) and the hemisphere verified as dominant for language. This study sought to discern whether asymmetry in occipital pole area is more predictive of the hemisphere dominant for language. Language dominance was identified by the Wada test in 55 patients evaluated for surgical treatment of epilepsy. In a blinded fashion, an examiner measured bilateral occipital pole area on MRIs for each patient. Asymmetry of the occipital pole area on the MRI made at 10 mm above the tentorium was significantly related to language dominance. This two-dimensional analysis was better than previously described linear measurements in discriminating patients with left-hemisphere dominance for language.