CAJ | 학술논문

目的：优化患者CT扫描参数，减少其辐射危害。方法以成人头部，胸部和腹部CT扫描为考察对象，应用CT专用16 cm直径CTDI测量模体，改变kVp和 mAs组合，测量所扫描图像的噪声，高对比分辨率，低对比分辨率等，以此为依据决定图像是否合格，并从合格影像中选出辐射剂量最小的一组kVp/mAs做为最优化结果。结果在噪声，高对比分辨率，低对比分辨率等都合格的情况下，各部位辐射剂量最小的一组kVp/mAs分别是：130/90（成人头部），110/70（成人胸部），130/65（成人腹部）。其辐射剂量相对设备预设条件下的辐射剂量下降百分比分别是：25．0％，12．0％和34．3％。结论体模实验证明，合理组合kVp和mAs设置可以在保证图像质量的情况下降低CT辐射剂量，从而为临床实际的CT剂量最优化提供借鉴。
목적：우화환자CT소묘삼수，감소기복사위해。방법이성인두부，흉부화복부CT소묘위고찰대상，응용CT전용16 cm직경CTDI측량모체，개변kVp화 mAs조합，측량소소묘도상적조성，고대비분변솔，저대비분변솔등，이차위의거결정도상시부합격，병종합격영상중선출복사제량최소적일조kVp/mAs주위최우화결과。결과재조성，고대비분변솔，저대비분변솔등도합격적정황하，각부위복사제량최소적일조kVp/mAs분별시：130/90（성인두부），110/70（성인흉부），130/65（성인복부）。기복사제량상대설비예설조건하적복사제량하강백분비분별시：25．0％，12．0％화34．3％。결론체모실험증명，합리조합kVp화mAs설치가이재보증도상질량적정황하강저CT복사제량，종이위림상실제적CT제량최우화제공차감。
Objective To optimize CT scanning parameters in routine examination and to reduce its radiation hazards . Methods A survey of radiation doses in computed tomography protocols was performed with phantoms and ionization chamber .Changes in kVp and mAs were proposed and the average noise ,contrast and spatial resolution were determined . Qualifying images were submitted to assessment of dose reduction .Results The reduction in dose achieved ranged be-tween 3.8% and 25% for adult skull ,9 .6% and 34 .3% for abdomen ,6 .4% and 12% for chest .Keeping the image quali-ty at acceptable levels ,the scanning protocols (kVp /mAs) for the minimum radiation dose were 130/90 (adult head) 110/70 (adult chest) ,130/65 (adult abdomen) .Conclusion Radiation dose levels can be reduced by optimizing CT scan-ning parameters ,keeping the noise at acceptable levels .