頭蓋外内頸動脈解離に対する頸動脈ステント留置術前後の評価に 経口腔頸動脈超音波検査（transoral carotid ultrasonography）が有用であった1例

A 40-year-old man with a history of carotid artery stenting for symptomatic left internal carotid artery (ICA) dissection presented to our hospital to undergo treatment for spontaneous asymptomatic right internal carotid artery (ICA) dissection. Carotid angiogram revealed the dissection of the right ICA and formation of a dissecting aneurysm with a false lumen with blood flow. Transoral carotid ultrasonography (TOCU) revealed the entry and re-entry points of the false lumen with high blood flow, and the true lumen was stenosed secondary to the expanded false lumen. Carotid artery stenting of the right ICA was performed. Postoperative TOCU revealed loss of blood flow in the thrombosed false lumen, and the true lumen was expanded satisfactorily with no stenosis. TOCU allows evaluation of the extracranial ICA, which is not possible with conventional carotid artery ultrasonography. Our case suggests that pre- and post-evaluation by TOCU for carotid artery stenting in ICA dissection appears effective.