The superior longitudinal fasciculus and speech arrest.

We present a 59-year-old woman with recurrent glioblastoma multiforme involving the left medial frontal and cingulate gyri. Diffusion tensor imaging (DTI) showed inferior-lateral tumor border proximity to the superior-medial (supracallosal) portion of the left frontal superior longitudinal fasciculus (SLF). Dissections of the tumor border contacting the dominant SLF caused speech arrests 8 times, with full recovery. At postoperative day 2, edema caused transient mild aphasia and paraphasic errors. Postoperative DTI showed an inferior-lateral resection cavity in immediate proximity to the supracallosal aspect of the left SLF. The case demonstrates excellent correlation between tumor border proximity to the dominant SLF shown at DTI and speech deficits caused by intraoperative dissections and postoperative edema. The case is the first to demonstrate speech arrest associated with lesion proximity to the supracallosal aspect of the SLF. Other SLF-related deficits are reviewed.