特発性正常圧水頭症の最新画像診断

Recent Developments in Diagnostic Imaging for Idiopathic Normal Pressure Hydrocephalus

特発性正常圧水頭症（idiopathic normal pressure hydrocephalus：iNPH）は，原因不明の脳脊髄液の循環不全により認知機能障害，歩行障害，尿失禁をきたす疾患である。近年では，脳血流画像，拡散テンソル画像など機能的変化を捉えるさまざまなモダリティや画像解析法が開発され，正常圧水頭症の発症機構が明らかになりつつある。本論ではiNPHの画像診断の歴史，および近年の画像診断法について述べたい。

Abstract

Idiopathic normal pressure hydrocephalus (iNPH), a syndrome characterized by cognitive impairment, gait abnormalities, and urinary incontinence attributable to cerebrospinal fluid circulatory insufficiency, is associated with an obscure etiology. Several methodologies and imaging analysis techniques, including visualization of cerebral hemodynamics and diffusion tensor imaging have emerged in recent years to determine functional alterations in cases of iNPH. These advancements have led to more comprehensive understanding of the pathophysiological mechanisms underlying iNPH. In this article, we discuss the historical evolution of imaging modalities for iNPH and contemporaneous imaging techniques designed to acquire deeper insight into this disease.