Two elderly patients with idiopathic normal pressure hydrocephalus diagnosed by head MRI and tap test

Abstract

AbstractDementia, gait disturbance and urinary incontinence were noted in two elderly patients, and diagnosed as idiopathic normal pressure hydrocephalus (iNPH). Case 1 was a 79‐year‐old man in whom dementia symptoms appeared 2 years ago. Gait disturbance and urge incontinence of urine developed later, and the patient visited our hospital. Walking was wide‐based and frozen gait was noted at the time of visiting our hospital. The mini‐mental state examination (MMSE) score was 11. A head MRI detected expansion of the cerebral ventricles and sylvian fissures, and narrowing of the cerebral fissures and the subarachnoid space in the higher convexity region. The diagnosis of iNPH was made based on the clinical symptoms and imaging findings, and a shunt operation (cerebrospinal fluid shunt) was performed in the neurosurgery department. Gait disturbance and cognitive function slightly improved after the operation. Case 2 was an 81‐year‐old woman who had had brachybasia for 1 year, and swayed from side to side while walking. Since disorientation and urge incontinence transiently occurred, the patient visited our hospital. The MMSE score was 24. Head MRI findings were similar to those in case 1. The cerebrospinal tap test was performed, and walking improved in the 1‐week course observation. iNPH is not very well recognized, compared to secondary NPH, and is likely to be overlooked because differentiation from Alzheimer's disease and vascular dementia based on symptoms and imaging is difficult in elderly patients. As iNPH is treatable by accurate diagnosis and therapy, the accumulation of cases indicated for shunt operation may be necessary.