頸動脈狹窄會減少供應大腦血流量、提高中風的風險，屬於侵入性檢查的數位減贅血管攝影(Digital Subtraction Angiography, DSA)，一直以來被認為是確認血管狹窄的黃金標準，然而隨著電腦斷層技術不斷更新，對於非侵入性的電腦斷層血管攝影(Computed Tomography Angiography, CTA)檢查逐漸成為趨勢。本研究以DSA為評估標準，評估CTA 與DSA 兩者對於頸動脈狹窄的差異性。研究為回顧性研究收集2018 年9 月到2019 年7月，共22 位疑似頸動脈狹窄的病人，利用DSA 和CTA 量測內頸動脈的狹窄率，並利用特徵曲線(Receiver Operating Characteristic curve , ROC)進行分析，結果顯示CTA 所量測狹窄率會有高估的現象，但仍然有達到DSA 診斷頸動脈狹窄的標準。而對於病人而言，CTA 是一項相對低風險且又能達到頸動脈狹窄診斷的檢查之一。

The carotid stenosis will reduce the supply of blood to the brain and increases the risk of stroke. The Digital Subtraction Angiography (DSA) has considered the gold standard for confirming vascular stenosis, but it is an invasive and has certain risks. The continuous updating of computer tomography technology, non-invasive computed tomography angiography (CTA) examination has gradually become a trend. In this study, DSA was used to evaluate the difference between CTA and DSA for carotid stenosis. The study was a retrospective study of 22 patients with suspected carotid stenosis. DSA and CTA were used to measure the rate of stenosis of the internal carotid artery, and a receiver operating characteristic (ROC) curve was used for analysis. The results show that the stenosis rate measured by CTA will be overestimated, but it still meets the DSA diagnostic criteria for carotid stenosis. For patients, CTA is a low-risk and can reach a certain diagnosis.