脳血管性アミロイドアンギオパチーにおける硬膜関与のメカニズム

Cerebral Amyloid Angiopathy (CAA) is a neurovascular condition characterized by the accumulation of amyloid-beta (Aβ) in the walls of small blood vessels, particularly affecting the leptomeninges and cortical regions in elderly populations. Initially recognized for its association with spontaneous lobar intracerebral hemorrhage, recent studies have highlighted the broader implications of CAA on cognitive decline and vascular health. This narrative review aims to elucidate the mechanisms of dural involvement in CAA, an aspect that has been largely overlooked in existing literature. This paper provides a detailed examination of the potential role of the dura mater and its associated lymphatic system in the clearance of interstitial amyloid and the maintenance of cerebrospinal fluid (CSF) homeostasis. Dural lymphatic vessels may facilitate the efflux of Aβ from the brain, and any impairment in this drainage system could contribute to the pathological accumulation of amyloid, exacerbating CAA and its neurological consequences. Additionally, the significant association between CAA and subdural hematoma (SDH) has been explored, indicating that the presence of SDH may complicate the clinical management of CAA patients by signaling an increased risk of hemorrhagic events. The mechanisms linking CAA and SDH, including vascular fragility and chronic inflammatory processes, are discussed to provide insight into potential pathways for therapeutic intervention.