Background The hyperdense lesion on non-contrast CT (NCCT) is a common postoperative phenomenon in acute ischemic stroke (AIS) patients who are treated with endovascular therapy (EVT). Both contrast extravasation and hemorrhagic transformation presented hyperdense lesions on NCCT, which are sometimes difficult to distinguish them. Summary of Review Radiographic findings are important for identifying contrast extravasation and hemorrhagic transformation. We recommended a standardized follow-up protocol involving imaging and clinical evaluation as it will allow neurologists and neuroradiologists to reveal the relationships between these hyperdensities and various clinical outcomes. Key Messages Dual-energy CT and susceptibility weighted imaging are capable of distinguishing contrast extravasation and hemorrhagic transformation at an early stage after EVT. However, in institutions without access to such technology, a follow-up protocol based on NCCT is crucial.

中文翻译：

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急性缺血性卒中血管内治疗后 CT 高密度病变：影像学表现及临床意义。

背景 平扫CT（NCCT）上的高密度病变是接受血管内治疗（EVT）治疗的急性缺血性脑卒中（AIS）患者的常见术后现象。造影剂外渗和出血性转化在NCCT上均表现为高密度病灶，有时难以区分。综述总结放射线检查结果对于识别造影剂外渗和出血性转化非常重要。我们推荐了一种涉及成像和临床评估的标准化后续方案，因为它将允许神经科医生和神经放射科医生揭示这些高密度与各种临床结果之间的关系。关键信息 双能 CT 和磁敏感加权成像能够在 EVT 后早期区分造影剂外渗和出血性转化。然而，在无法获得此类技术的机构中，基于 NCCT 的后续协议至关重要。