Acetazolamide-enhanced neuroSPECT scan reveals functional impairment after minimal traumatic brain injury not otherwise discernible.

A patient suffering from aggressive personality changes and cognitive impairment following head trauma, without neurological or anatomical imaging findings, underwent neuroSPECT scans with and without acetazolamide injection, both before treatment and during treatment with valproate. Acetazolamide injection induced increased prefrontal perfusion not evident at baseline. Valproate treatment was associated with increased prefrontal perfusion concomitant with clinical improvement and abolished response to acetazolamide challenge.