以直立性頭暈為表徵之椎基底動脈畸形

Anomaly of Vertebral-Basilar Artery Presenting as Orthostatic Dizziness

陳建志(Jiann-Jy Chen) ； 劉智仰(Chih-Yang Liu) ； 陳登郎(Dem-Lion Chen) ； 楊菁華(Chin-Hua Yang)

《童綜合醫學雜誌》 3卷1期 (2009/06) Pp. 51-55

https://doi.org/10.29838/TMJ.200906.0008

摘要

姿態性頭暈可能為頸項性疾病、與內耳有關的週邊性眩暈、偏頭痛性眩暈、基底動脈缺血、自律神經失調、顱內壓過低或、姿態性低血壓或其他不明之病因。-58歲男性，因反覆直立性頭暈半年求診於本院。理學檢查無異常發現，但換氣過度測試可以引發明顯的頭暈。血液學檢查均為正常，純音聽力檢查、眼振電圖及兩耳溫差測試均無異常發現，頸椎X光無異常發現，頸部血管超音波顯示右側椎動脈血流過小，兩側頸動脈均有輕度的動脈硬化。最後，血管磁振造影顯示(1)基底動脈過長彎曲，(2)右側椎動脈直接灌入後下小腦動脈，並未與基底動脈相連，及(3)左側後下小腦動脈發育不全。推測患者症狀可能是直立或坐立過久時，血液蓄積於下半身，輸入中樞神經的血流不足，引起後顱窩循環之血流不穩，接著引起小腦與腦幹缺血性的障礙，引發頭暈。建議調整生活習慣，並給予抗血小板劑及腦循環促進劑。1個月後，病症已經消失；追蹤迄今已逾半年，情況依然穩定。鑒於該椎基底動脈之畸形與臨床症狀之關聯，文獻中少有討論，特報告此個案。

關鍵字

直立性頭暈 ； 後顱窩循環 ； 椎基底動脈 ； 椎動脈 ； 後下小腦動脈

並列摘要

Positional dizziness might result from cervical origins, peripheral vertigo, migrainous vertigo, basilar artery (BA) insufficiency, dysautonomia causing orthostatic hypotension, intracranial hypotension and/or other unknown etiologies. A 58-year-old male who visited our clinic having a history of frequent orthostatic dizziness for the past six months. His physical examinations were normal, except that hyperventilation test could induce an obvious dizziness. All data on the hematological examination were normal. Pure tone audiometry, electronystagmogram and caloric test were reported normal, and so did cervical spinal X-ray. However, duplex scanning of neck vessels showed a mild atherosclerosis of bilateral carotid artery and decreased blood flow of right vertebral artery (VA). Finally, magnetic resonance angiogram showed some atypical findings, namely: (1) dolicho-tortuosity of BA, (2) right VA directly ended in right posterior inferior cerebellar artery (PICA) instead of BA, and (3) hypoplasia of left PICA. It can be surmised that patient’s blood accumulated in the lower half of trunk after prolonged standing or sitting; and subsequently resulted in the decrease of venous return and cerebral perfusion. The anatomical anomaly of vertebral-basilar artery further accentuated ischemia of cerebellum and brainstem when cerebral perfusion decreased. This situation could thus lead to the occurrence of dizziness. The patient was then advised to adjust his life style and taken an antiplatelet and a brain circulatory enhancer for a month, dizziness was subsided. During a subsequent following up for six months, the patient remained free of symptoms. The anatomical anomaly of vertebral-basilar artery is rarely discussed in the literature, so we hereby report the case.

並列關鍵字

orthostatic dizziness ； posterior circulation ； vertebral-basilar artery ； vertebral artery ； posterior inferior cerebellar artery