可能導因於椎動脈發育不全與基底動脈扭曲之單側姿態性搏動性耳鳴

Vertebral Artery Hypoplasia and Twisted Basilar Artery Might Contribute to Unilateral Positional Pulsatile Tinnitus

搏動性耳鳴需考慮腫瘤性或血管性的病灶。一42歲女性，每每於夜間睡眠平躺，頭向左側轉時就會引發右側搏動性耳鳴，鑒於病症已經10年，求診於本院。經過理學檢查、聽力檢查、動脈超音波及合併血管造影之磁振造影等一系列的檢查後，證實為右側椎動脈發育不全及基底動脈彎曲，尚無其他異常。本個案在服用β受體拮抗劑1週後，病症消失，但只要停止服藥，病症會復發。經過半年的追蹤，情況依然穩定，再追蹤其動脈超音波。我們認為，應是本個案向左轉頭時，引起椎基底動脈之血流動力學變化，造成右側搏動性耳鳴。由於臨床上搏動性耳鳴不算多見，但大多數原因不明，特報告此個案。

Pulsatile tinnitus (PT) might be attributable to a neoplasm or vascular lesion. A 42-year-old female has been bothered with right PT when lying in bed and a leftward rotating head every night for ten years. The physical examination, audiometry, colorcoded duplex sonogram and magnetic resonance image/angiography revealed unremarkable, except the right vertebral artery hypoplasia and a twisted basilar artery. After she had regularly taken an β-antagonist for a week, the PT subsided. However, the PT would recur if she halted medication. Over the following half a year, it was uneventful and color-coded duplex sonogram was the follow-up. We suggest hemodynamic change of the vertebral-basilar artery secondary to leftward head rotation led to her right PT. PT is clinically uncommon, and most of them are of unknown etiology, so we report the case herein.