PTCA後放置血管支架有許多有益的結果，但是血管支架內再阻塞仍然是存在的一個嚴重問題，就好像原來的冠動脈也會發生阻塞一樣。核醫鉈-201心肌灌注掃描加上SPECT因具有很高之偵測性，因此近年來之醫學文獻以證明其能有效地用於偵測再通血管過程後的再阻塞。一位罹患多條冠心病女病人接受了了六次PTCA，放置了四個血管支架，並接受了七次鉈-201心肌灌注掃描作追?。每次掃描的結果的均呈現清楚的血流缺損分佈型態，包括固定缺損合併逆行分佈，結合固定缺損與逆行分佈，變大的外側壁缺損與變小的下壁缺損，更大的外側壁缺損與更小的下壁缺損，較小的外側壁固定缺損以及下壁更明顯的可逆缺損，更小的外側壁缺損與改善下壁血流。這些病灶位置包括左心室外側壁，下外側壁，下心尖，外心尖壁。這些造影位置的發現與一系列的心導管結果有高度的一致性。此例印證了鉈-201心肌灌注掃描加上單光子斷層攝影的確是一個有效且適合的檢查，因其可偵測經再血管化過程，放置血管支架後再阻塞情形，並且可以清楚的看到治療性血管支架內再阻塞的再通暢結果，以及心肌梗塞後經適當治療的小部分存活心肌，打破心肌灌注掃描只有用於PTCA之前評估的觀念，證明它們也可以用於PTCA之後的評估。

　　　　　Despite the beneficial outcomes of percutaneous trans-luminal coronary angioplasty (PTCA) with stent placement, in-stent restenosis continues to be a clinical problem just as significant as stenosis of native coronary arteries. 201TI-thallous chloride myocardial single photon emission computed tomography (SPECT) has been proven to be a sensitive diagnostic modality for detecting restenosis after revascularization procedures, because it provides a reliable evaluation of the consequences of the stenosis of myocardial perfusion. A patient with multivessel disease of coronary artery underwent six PTCAs with four stent placements, and received seven consecutive dipyridamole 201TI-thallous chloride myocardial SPECTs for follow-up. Each SPECT showed a distinct tracer distribution pattern including a fixed defect with reverse redistribution, reverse redistribution with reversible defect, more fixed defect in lateral wall with improving perfusion in inferior wall, more fixed defect in lateral wall with improving per- fusion in inferior wall, smaller fixed defect in lateral wall with more ischemia in inferoapex, more reperfusion of the scar formation site of lateral wall with more ischemia in inferior wall, smaller fixed defect in lateral wall with reperfusion in inferior wall. The sites of involving segments included the lateral, inferolateral, and/or inleroapical, and lateroapical walls of the left ventricle. These findings were correlated well with the clinical manifestations and angiographic findings of sequential PTCA. Therefore, 201TI SPECTs not only detect the in- stent restenosis, but also show the restenosis of native coronary arteries. Since it is a non-invasive procedure in identifying the status of stented vascular territory, repeated follow-up 201TI-thallous chloride myocardial SPECTs are suitable and useful for monitoring in-stent restenosis or stenosis of native coronary arteries before and after revascularization procedures and after stent placement. In addition, 201TI SPECT can be used to assess viable myocardium after myocardial infarction.