64层螺旋CT冠状动脉图像质量控制研究:最佳重组时相与心率关系  

Correlation Between Reconstruction Interval and Heart Rate in Image Quality Control of 64-slice Spiral Computed Tomography Angiography for the Coronary Arteries

作　　者：胡斌[1] 徐文坚[2] 张通[1] 陈海松[2] 王国华[1] 

机构地区：[1]山东省青岛市市立医院CT室,研究生266011 [2]青岛大学医学院附属医院放射科,266003

出　　处：《临床放射学杂志》2010年第4期530-534,共5页Journal of Clinical Radiology

基　　金：青岛市科技局资助项目(编号:06-2-2-4-nsh-2)

摘　　要：目的量化评估64层螺旋CT冠状动脉各分支不同重组时相图像质量,探讨冠状动脉CT成像最佳重组时相与心率关系。资料与方法102例患者均采用64层螺旋CT回顾性心电门控冠状动脉成像,男68例,女34例,平均年龄(58.1±9.7)岁,平均心率(66.4±11.5)次/min。心率<65次/min(n=43)为Ⅰ组,65～75次/min(n=34)为Ⅱ组,>75次/min(n=25)为Ⅲ组,每例患者的4支冠状动脉(左主干、左前降支、左回旋支、右冠状动脉)共分为12个节段用于图像质量分析。扫描原始数据以间隔5%在20%～80%时相分别回顾性重组冠状动脉图像,采用横断位、曲面重组、容积再现等方法对图像质量综合评分。结果Ⅰ组60%、65%和70%为最佳时相,Ⅱ组60%、65%时相为最佳时相,Ⅲ组右冠状动脉较优时相为35%、40%,左冠状动脉较优时相为60%、65%。结论心率和重组时相的选择是决定冠状动脉图像质量的重要因素。平均心率≤75次/min,冠状动脉各分支图像质量在心脏运动的舒张中期(60%、65%)最佳;>75次/min时,左右冠状动脉分别进行重组能明显提高冠状动脉的成像质量。Objective To explore the optimal reconstruction interval that related to heart rate by analyzing quantitative parameters of image quality in consecutive patients undergoing 64-slice computed tomography coronary angiography.Materials and Methods Electrocardiography （ECG）-gated 64-slice scanner（64 mm×0.6 mm collimation,330 ms per rotation,870mAs,120 kV） CT coronary angiography was performed in 102 patients（68 males,34 females; mean age （58.1±9.7）years old,mean heart rate [（66.4±11.5） bpm]. Data sets were reconstructed in 5% increments from 20% to 80% of the R-R interval. Patients were divided into 3 groups：group I （65 bpm,n=43）,group II （65-75 bpm,n=34） and group III （75 bpm,n=25）.Three blinded and independent readers assessed the image quality of 12 coronary segments in left main,left anterior descending,left circumflex and right coronary artery using the following scores：5,no motion artifacts; 4,minor artifacts; 3,moderate artifacts; 2,severe artifacts; and 1,not valuable.Results Best image quality was found in coronary segments at 60%,65% or 70% for group Ⅰand 60% or 65% for group Ⅱ.In group Ⅲ,The left coronary artery were clearly visualized at 60%,65% of R-R phases,while the right coronary artery was seen at 35%,40% of R-R phases.Conclusion Image quality is influenced by heart rate and reconstruction interval,at heart rates ≤75 bpm,64-slice CT coronary angiography provides best image quality in mid-diastole （60%,65%）,at heart rates 75 bpm,the right and left coronary artery should be reconstructed respectively to improve the image quality of coronary.

关 键 词：体层摄影术 X线计算机 冠状动脉血管造影 重组时相 

分 类 号：R816.2[医药卫生—放射医学]