Introduction Post-thrombectomy subarachnoid haemorrhage (SAH) can result in oculomotor palsy and drowsiness, which may falsely suggest transtentorial herniation. Case presentation We present a case of right oculomotor nerve palsy presenting after endovascular thrombectomy (EVT) for a right middle cerebral artery (MCA) stroke. The patient presented with a significant right MCA syndrome and a National Institutes of Health Stroke Scale (NIHSS) score of 10 with CT perfusion demonstrating a large penumbral lesion and a CT angiogram confirming a right MCA M1 occlusion. After thrombectomy, the patient developed a 9mm dilated non-reactive right pupil, and a new ipsilateral near-complete oculomotor nerve palsy. Repeat code stroke imaging demonstrated perimesencephalic SAH). The patient was managed expectantly and her conscious state and oculomotor palsy gradually resolved with an excellent neurological recovery. Conclusion This case underscores the potential for post-thrombectomy perimesencephalic SAH as a rare mimic of symptomatic intracranial haemorrhage with mass effect manifesting as sudden-onset oculomotor nerve palsy. Data sharing not applicable as no datasets generated and/or analysed for this study. Short report of case.

中文翻译：

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血栓切除术后蛛网膜下腔出血导致动眼神经麻痹和嗜睡，错误提示小脑幕疝

简介 血栓切除术后蛛网膜下腔出血 (SAH) 可导致动眼神经麻痹和嗜睡，这可能会错误地提示小脑幕疝。病例介绍 我们介绍一例因右大脑中动脉（MCA）卒中而接受血管内血栓切除术（EVT）后出现的右侧动眼神经麻痹的病例。该患者出现明显的右侧 MCA 综合征，美国国立卫生研究院卒中量表 (NIHSS) 评分为 10 分，CT 灌注显示大的半影病变，CT 血管造影证实右侧 MCA M1 闭塞。血栓切除术后，患者右瞳孔扩大 9 毫米，无反应，并出现新的同侧近完全性动眼神经麻痹。重复代码中风成像显示中脑周围SAH）。患者得到了预期的治疗，她的意识状态和动眼神经麻痹逐渐消失，神经系统恢复良好。结论 该病例强调了血栓切除后中脑周围 SAH 可能是一种罕见的症状性颅内出血症状，伴有占位效应，表现为突发性动眼神经麻痹。数据共享不适用，因为本研究没有生成和/或分析数据集。案件简短报告。