Auditory event-related potentials differentiate patients with normal pressure hydrocephalus and patients with concomitant Alzheimer's disease verified by brain biopsy

We studied 51 patients with clinical symptoms and CT findings suggesting no rmal pressure hydrocephalus (NPH). Tests included head MRI, auditory event- related potentials (ERPs), thorough neuropsychological testing and intraven tricular intracranial 24 h pressure recording and infusion testing. A brain biopsy was also obtained to verify a concomitant dementing process (Alzhei mer's disease; AD). Patients were divided into subgroups according to the n eed of shunt and the biopsy findings, and their ERPs were analysed blindly. The present results suggest that non-invasive ERPs aid in the differentiat ion of pure NPH from NPH with concomitant AD. NeuroReport 12:33-37 (C) 2001 Lippincott Williams & Wilkins.