调整螺距对64层螺旋CT冠状动脉成像图像质量的影响

Impact of imaging quality of change pitch on coronary CTA with 64-detector row CT

目的探讨64层螺旋CT调整螺距对冠状动脉成像图像质量的影响。方法对566例患者进行64层螺旋CT心脏冠状动脉成像，以容积再现（vR）、最大密度投影（MIP）和曲面重组（CPR）等技术行冠状动脉三维成像，以心率≤50、51-70、71-80及≥80次／min分为4组，每组随机分为常规组及修改组，采用常规螺距及修订螺距扫描，评价图像质量，分析其影响。结果4组组间冠状动脉成像优良率差异有统计学意义（P〈0.05），各组间不同螺距图像质量差异有统计学意义（P〈0.01）。对心率较快（71-80次／min）或（≥80次／min）但心率整齐，更改螺距能有效提高图像质量，达到诊断目的。结论64层螺旋CT冠状动脉成像通过调整螺距能有效提高心率较快时图像质量，达到优化诊断的效果。

Objective To investigate the impact of imaging quality of pitch on coronary CT angiography （CTA） with 64-detector row CT. Methods 566 patients were divided into four groups according to heart rate （≤50,51-70,71 - 80 and ≥80 bpm）. Three dimensional reconstructions were used such as volume rendering （VR）, maximum intensity projection （MIP） and curved planar reformation（CPR）. Each group was divided into control group and experimential group randomly, using normal pitch and revised pitch respectively, and the imaging quality and influencing factors were analyzed among the four groups. Results There was significant difference in imaging quality among the four groups （P 〈 0.05）. Each group had difference in imaging quality with normal pitch and revised pitch. Conclusions The revised pitch helps to improve the imaging quality and meet the demand of diagnosis.