目的：瞭解鎝－99m標幟紅血球連續造影對判斷胃腸道出血定位之正確性。方法：我們收集本院自1999年8月至2004年3月之鎝－99m標幟紅血球造影結果為陽性且經其他檢查或手術證實為陽性之患者，比對定位之差異。結果：鎝－99m標幟紅血球連續造影檢查正確定位30位患者中之21位(70%)及34個出血病灶造影檢查之24個(71%)。以出血區域來分，判斷胃出血正確率為88%，小腸為56%，而結腸為100%。此外，對於六名有接受胃腸手術病史的患者，發現其中五位出血點與先前手術部位一致。結論：鎝－99m標幟紅血球連續造影對於出血點定位具高診斷率。病患之開刀史對確定出血點位置有重大幫助。

Purpose: To evaluate the accuracy of correct localization of gastrointestinal (GI) bleeding by 99mTc-red blood cell (RBC) scans. Methods: We reviewed our records with 30 patients and 34 positive cinematic RBC scans for GI bleeding from Aug. 1999 to Mar. 2004, and compared with the records from other examinations including panendoscopy, abdominal computed tomography (CT), angiography and colonic scope, and prior surgical procedure were also reviewed, to evaluate the accuracy of our records. Results: Thirty patients with 34 positive cinematic RBC scans were enrolled. Twenty-one of the 30 patients (70%) and 24 of the 34 scans (71%) were successful to localize the bleeding sites by cinematic RBC scans, the accuracy of cinematic RBC scans compared with other examinations or operation was 88% for gastric bleeding, 56% for small intestinal bleeding and 100% for colonic bleeding. Among 30 patients, 5 of 6 patients with recent operation history for GI bleeding were proven that their recurrent bleeding was happened at the formal operation site. Conclusion: The cinematic RBC scans have high accuracy of correct localization of GI bleeding and the operation history of patients is important clue to determine location of bleeding sites.