頸部内頸動脈偽閉塞症の病態と頸動脈血栓内膜剥離術の妥当性  [in Japanese] Carotid Endarterectomy for Atheromatous Pseudo-occlusion of the Internal Carotid Artery  [in Japanese]

頸部内頸動脈偽閉塞症atheromatous pseudo-occlusion of the internal carotid arteryは, 1980年にShekharらによって報告された病態である. この病態では, 頸部内頸動脈起始部に高度な動脈硬化性狭窄病変が存在し, 末梢側の内頸動脈の灌流圧が低下し, 動脈内腔が虚脱した状態を呈しているとされている. この病態に対しては, 頸部内頸動脈起始部の高度狭窄病変の切除による血流改善に伴って, 狭窄部より遠位部の形態も正常化する可能性があり, 頸動脈血栓内膜剥離術carotid endarterectomy(CEA)の有効性が示されてきている. これまでに脳血管撮影上, 頸部内頸動脈偽閉塞症と診断された8例に関して, 臨床経過, 画像所見, 手術所見などを検討して, 本病態の特徴に関して検討するとともに治療としてのCEAの妥当性を検討した. 対象および方法 対象は当施設でCEAが施行された266例中8例である. 年齢は52から78歳で平均は68歳, 全例男性であった.

Pseudo-occlusion of the internal carotid artery has been subdivided from carotid near occlusion, and defined as a more severely stenosed group. Angiographic characteristics of pseudoocclusion include "string like" residual filling of the internal carotid artery (ICA) beyond the carotid bifurcation, and retrograde filling of the ICA via the ophthalmic artery reaching the skull base. Eight patients with pseudo-occlusion were treated with carotid endarterectomy. Clinical features, radiological findings, and operative records were retrospectively examined. Four patients presenting progressing strokes and 1 presenting minor stroke were treated in an acute period, and 2 patients presenting minor strokes and 1 presenting transient ischemic attack (TIA) in a chronic period after their last ischemic attack. All patients had suffered from recent TIA confined to the ipsilateral carotid artery territory. The pattern of ischemic brain lesions evaluated by means of computed tomography and magnetic resonance imaging revealed that most of the subjects had a hemodynamic pathogenesis. Ischemic brain lesions suggesting embolism were also found in 2 cases in an acute period. CEA was successfully performed in ail patients. Intraoperatively, a patent but collapsed ICA distal to a localized atheromatous plaque was recognized in all cases. CEA is benefit for patients with pseudo-occlusion of the intemal carotid artery.