Idiopathic Normal Pressure Hydrocephalus with Stuttering: Report of Two Cases and Review of the Literature.

Abstract Idiopathic normal pressure hydrocephalus (iNPH) is a disorder of aging that is characterized by enlarged cerebral ventricles, gait apraxia, dementia, and urinary incontinence. iNPH is frequently misdiagnosed, in part because the symptoms resemble other neurological disorders, and because other associated symptoms have not been fully characterized. Importantly, iNPH has not previously been associated with stuttering, and shunting has not been shown to alleviate the symptom of stuttering. Here, the authors report two cases of patients with iNPH presenting with stuttering that resolved after ventriculoperitoneal (VP) shunt placement. Each patient presented with gait difficulty, incontinence, cognitive impairment and stuttering. Lasting improvements of the symptoms (including stuttering) were seen in both patients after CSF drainage procedures that included lumbar puncture, extended lumbar CSF drainage, placement of a VP shunt, and VP shunt revision. These findings suggest that iNPH can present with stuttering or dysarthria. The significant improvement in stuttering and dysarthria, along with the improvements in gait difficulty, incontinence, and cognitive impairment that occurred after CSF drainage, suggests that the motor apraxia observed in NPH can affect speech production. Practitioners should be aware that iNPH can present with stuttering, and that CSF drainage can improve stuttering in select circumstances.