我們報告一位66歲的女性病人，她過去病史有高血壓，糖尿病，高血脂症和二尖瓣脫垂，來門診的主訴為在3小時前昏倒並撞到頭後的持續性頭暈。她意識清楚且定向良好，所有神經檢查結果（包括格拉斯哥昏迷量表、簡短智能測驗、顱神經檢查，肌力評估和巴賓斯基反射）和其他身體檢查均為正常。但由於年齡大於60歲，她在外傷後有相對高風險會發生腦出血。因此安排她做腦部電腦斷層，並發現了急性硬腦膜下血腫。在台灣，人口老齡化已成為一種趨勢，而頭暈為老年患者常見的主訴，且其原因也多樣化。因此藉由此病例分享，在面對老年患者頭部外傷後的頭暈時，須謹慎評估其伴隨的併發症。

Population aging has become a trend in Taiwan, and dizziness is commonly reported by older adults. We present the case of a 66-year-old woman with a history of hypertension, diabetes mellitus, hyperlipidemia, and mitral valve prolapse who reported persistent dizziness for 3 hours just after syncope and hitting the back of her head on a table. On arrival, she was fully conscious and well oriented, and all results of neurological examination [including Glasgow Coma Scale (GCS), Mini-Mental State Examination (MMSE), cranial nerves test, muscle power, and Babinski sign] and physical examination were normal. However, because of her age (>60 years), she was at high risk for brain hemorrhage after the trauma. She underwent brain computed tomography, which revealed acute subdural hematoma (SDH). Thence, we report a case of acute SDH in an older patient that initially presented as only persistent dizziness after head trauma.