陣發性姿態性眩暈有可能是單側顱內椎動脈病變所致。-59歲男性,罹患高血壓、高血脂症及粥狀動脈硬化,因反覆發作陣發性姿態性眩暈1年求診於作者。理學檢查、前庭功能檢查、心電圖、純音聽力檢查、眼振電圖及前庭誘發肌性電位均無異常發現,但溫差測試呈現異常。血管磁振造影顯示(1)兩側後交通動脈發育不全,(2)基底動脈扭曲,(3)右側顱內椎動脈扭曲及狹窄。可能是頭向左轉時,右側椎動脈之血管阻力大增,發生右側後下小腦動脈之血流不穩,影響到該側腦幹外側之上前庭神經根,造成眩暈。不僅建議繼續服用抗血小板劑及HMG-CoA還原抑制劑等保守治療,並避免頭長期間向左轉。自此,陣發性姿態性眩暈不再發作。
Paroxysmal positional vertigo (PPV) can be attributed to unilateral vertebral artery (VA) vasculopathy. A 59-year-old male was suffering from hypertension, hyperlipidemia, and atherosclerosis. He had presented with frequent PPV for one year. Physical examination, a vestibular function test, an electrocardiogram, an audiogram, and an electronystagmogram were all normal; however, a caloric test and the patient's vestibular evoked myogenic potential showed abnormalities. A time-of-flight angiogram showed (1) hypoplasia of the bilateral posterior communicating arteries, (2) tortuosity of the basilar artery, and (3) tortuosity and stenosis of the right intracranial VA. It is probable that vascular resistance within the right VA had increased and led to insufficiency of the right posterior inferior cerebellar artery; as a result the right superior vestibular nerve in peripheral brainstem was impaired and PPV was occurring. He continued to be treated conservatively with anti-platelet and HMG-CoA reductase inhibitor medications. In addition, he was asked to avoid longterm leftward rotation of his head. From this point onwards there have been no further PPV events.