Although contrast extravasation on follow-up head computed tomography (CT) is frequently visualized after endovascular treatment, this phenomenon is rare after intravenous thrombolytic treatment in patients with acute ischemic stroke (AIS). Here, we report a case of contrast extravasation mimicking intracerebral hemorrhage (ICH) with intraventricular extension after intravenous thrombolytic treatment and computed tomography angiography (CTA). A 52-year-old man presented with right-sided hemiparesis and hypoesthesia. Initial non-contrast head CT was negative for intracranial hemorrhage and acute ischemic changes. He received intravenous treatment with tenecteplase 3.8 h after the onset of stroke. CTA of the head and neck was performed at 4.3 h after stroke onset. It showed no stenosis or occlusion of the carotid and major intracranial arteries. At about 1.5 h after CTA, the right-sided hemiparesis deteriorated, accompanied by drowsiness, aphasia, and urinary incontinence. Immediate head CT showed hyperdense lesions with mild space-occupying effect in the left basal ganglia and both lateral ventricles. The hyperdense lesions were reduced in size on follow-up CT after 5 h. Two days later, CT showed that the hyperdense lesions in the lateral ventricles almost completely disappeared and only a small amount remained in the infarcted area. Contrast extravasation into the brain tissue and lateral ventricles, mimicking ICH with intraventricular extension, could occur after intravenous thrombolytic treatment and CTA in a patient with AIS, which might lead to misdiagnosis and wrong treatment of the patient. The rapid resolution of intracranial hyperdense lesions is key to differentiate contrast extravasation from ICH on serial non-enhanced CT.

中文翻译：

---

缺血性卒中静脉溶栓治疗后模拟脑内和脑室内出血的造影剂外渗：病例报告

尽管血管内治疗后随访头部计算机断层扫描（CT）中经常可见造影剂外渗，但在急性缺血性卒中（AIS）患者静脉溶栓治疗后这种现象很少见。在这里，我们报告一例在静脉溶栓治疗和计算机断层扫描血管造影（CTA）后出现类似脑出血（ICH）的造影剂外渗并伴有脑室内扩展的病例。一名 52 岁男性因右侧偏瘫和感觉减退就诊。最初的平扫头颅 CT 未发现颅内出血和急性缺血性改变。中风发作后 3.8 小时，他接受了替奈普酶静脉注射治疗。中风发作后 4.3 小时进行头颈部 CTA。结果显示颈动脉和颅内动脉没有狭窄或闭塞。 CTA后约1.5小时，右侧偏瘫加重，伴有嗜睡、失语、尿失禁。即刻头颅CT显示左侧基底节和双侧脑室有轻度占位的高密度病灶。 5小时后随访CT显示高密度病灶尺寸缩小。两天后，CT显示侧脑室高密度病灶几乎完全消失，梗死区仅残留少量。 AIS 患者静脉溶栓治疗和 CTA 后可能会出现造影剂外渗至脑组织和侧脑室，类似于 ICH 并延伸至脑室内，这可能导致患者的误诊和错误治疗。颅内高密度病变的快速消退是连续非增强 CT 上区分对比剂外渗和 ICH 的关键。