Beyond ASPECTS: A Practical Guide to CT Perfusion Interpretation

Computed tomography perfusion (CTP) imaging plays a pivotal role in the early evaluation of patients presenting with acute ischemic stroke (AIS), particularly by identifying candidates for endovascular thrombectomy. Accurate interpretation of CTP requires a structured approach that integrates technical understanding, clinical judgment, and recognition of the modality's limitations. This review was prompted by real clinical challenges faced by the senior author and aims to provide both a theoretical foundation and practical guidance for interpreting CTP. Key concepts are illustrated through real clinical scenarios and corresponding annotated images. In addition to reviewing current AHA/ASA guidelines, we discuss institutional best practices and highlight challenging clinical scenarios in which CTP can significantly influence treatment decisions. This article aims to equip clinicians with the knowledge and tools needed for consistent and effective use of CTP.