皮質性小脳萎縮症の病理

Neuropathology of Cerebellar Cortical Atrophy

皮質性小脳萎縮症は，小脳皮質と下オリーブ核に神経脱落が限局する神経変性疾患である。多系統萎縮症を除く孤発性の小脳失調症に対する臨床診断名として用いられることもあるが，本稿では自験例を通じて皮質性小脳萎縮症が純粋な小脳性運動失調以外に多様な症状を呈することを提示する。臨床像を問わず，小脳皮質と下オリーブ核に神経脱落が限局する疾患を包括的に指す病理診断名として皮質性小脳萎縮症は用いられるべきと考える。

Abstract

Cerebellar cortical atrophy (CCA) is a neurodegenerative disease characterized by the loss of Purkinje cells, frequently associated with atrophy of the inferior olivary nucleus. The diagnosis of CCA requires a pathologic assessment; however, this term has also been used in clinical practice as a diagnosis of exclusion for sporadic, adult-onset, and progressive ataxia. For the clinical diagnosis of CCA, diagnostic criteria for idiopathic cerebellar ataxia (IDCA) have been proposed. We herein describe two patients with a pathologic diagnosis of CCA. The first patient was clinically suspected to have Creutzfeldt-Jakob disease due to rapid progressive dementia and ataxia. The second patient was clinically diagnosed with progressive supranuclear palsy based on imbalance, frequent falls, and vertical gaze palsy. The se cases suggest that the clinical presentation of CCA is heterogeneous, and CCA does not always meet the criteria for IDCA. Therefore, the term CCA should be used solely for a pathologic diagnosis.