高心率患者256层螺旋CT低剂量前瞻性心电门控应用研究

The applied research of prospective ECG-gated 256 slice spiral CT with low radiation dose in high heart rate patients

目的利用Philips256层螺旋iCT探讨高心率患者前瞻性心电门控扫描的可行性，并评价图像质量。方法将2010年12月-2013年3月在本院行前瞻性心电门控CCTA检查的患者根据扫描前心率分成4组：a组：心率〈70bpm；b组：70bpm≤心率〈80bpm；C组：80bpm≤心率〈90bpm；d组：心率≥90bpm。每组连续选取30例患者，采用4分法评价图像质量，评分I〉2分为可诊断节段，并记录辐射剂量。结果b组图像质量和可诊断节段率（98．5％）与a组差异无统计学意义；c组、d组的图像质量明显下降，可诊断节段率分别为90．8％和79．5％，与a组差异有统计学意义。4组辐射剂量无明显差异。结论Philips256层螺旋CT前瞻性心电门控CCTA检查，适合心率可放宽至BPM〈80bpm的患者，且能有效控制患者的辐射剂量。

Objective To approach the feasibility of prospective ECG-gated 256 slice spiral CT in high heart rate （HR） patients, and evaluate the image quality. Methods All patients scanned with prospective ECG-gated coronary CT angiography （CCTA） in our hospital from December 2010 to March 2013 were collected and divided into four groups according to HR be- fore scan. Groupa, HR 〈70 beat per minute （bpm）; group b, 70 bpm≤HR〈80 bpm; group c, 80 bpm ≤HR 〈 90 bpm; and group d, HR I〉90 bpm. Thirty consecutive patients of each group were chosen and the image quality of them was evaluated by 4-score scale. The seg- ments which were scored higher than 2 could satisfy the diagnosis. The radiation dose was re- corded. Results The image quality and diagnostic rate （98.5%） of group b were not signifi- cantly different from group a. The image quality of group c and d descended obviously and the diagnostic rate were 90. 8% and 79.5%, respectively, which was significantly different from group a. There was no significant difference of the radiation dose between groups. Conclusion In prospective ECG-gated CCTA by 256 slice spiral CT, the suitable HR can be raised to 80 bpm. Besides, the radiation dose can be controlled effectively.