Tumors of Heschl's Gyrus: Report of Two Cases

Abstract

The clinical presentation and treatment of patients with lesions involving Heschl's gyrus is reported. Intraoperative bipolar cortical stimulation mapping of Heschl's gyrus has not been previously reported. Only monopolar stimulation of this region (with potential electrical recruitment of large areas of surrounding cortex) has been undertaken. Two patients with intrinsic brain tumors located in Heschl's gyrus, in the hemisphere dominant for speech, presented with interictal or ictal auditory changes. Craniotomies were performed with the patients awake and with intraoperative bipolar cortical stimulation mapping of language cortex and of Heschl's gyrus. In contrast to previous studies using monopolar cortical stimulation, auditory changes were not elicited by stimulation. In one of the patients, a persistent interictal ringing sound stopped abruptly during lesion resection. Neither patient had essential temporal lobe language cortex near the lesion. Lesions in Heschl's gyrus can be identified by clinical presentation and magnetic resonance imaging. Based on topographic anatomy, cytoarchitecture, and functional mapping data, these lesions may be resectable without language or auditory mapping, although further experience will be necessary to confirm this observation.