CAJ | 학술논문

目的探讨多层螺旋CT(MSCT)下肢动脉成像中应用低管电压(kVp,100 kV)设置和管电流调制减低辐射剂量的可行性.方法连续选取需行下肢动脉造影的患者61例,按随机数表随机分为A组(120 kV)、B组(100 kV)、C组(100 kV+管电流调制).比较3组患者的图像客观评价指标、图像质量主观评分以及辐射剂量.C组进一步按体重指数(BMI)分为C1组(BMI ＜24.9kg/m2)及C2组(BMI≥24.9 kg/m2),比较2组患者间的辐射剂量.结果 3组患者的主-髂部轴位、容积再现(VR)、最大强度投影(MIP)图像的主观质量评分均在良好以上,且3组图像的信噪比、对比噪声比差异无统计学意义(P＞0.05).A、B、C3组的有效吸收剂量分别为8.20、5.36和7.48mSv；B组较A组有效吸收剂量减低约34.6％,C组较B组有效吸收剂量增加约39.5％,且与A组比较差异无统计学意义(P＞0.05).C1组和C2组有效吸收剂量为7.11和9.69 mSv,两组比较差异有统计学意义(t=-3.163,P＜0.05),C1组较C2组有效剂量减低约26.6％.C1组较A组有效剂量减低13.3％(Z=-2.822,P＜0.05),但较B组有效剂量增加了32.6％(Z=-3.900,P＜0.05)；C2组较A组有效吸收剂量增加18.2％ (P ＞0.05),较B组有效剂量增加了80.8％(Z=-3.426,P＜0.05).结论下肢动脉MSCTA运用低kVp设置(100 kV)能在保证图像质量的同时降低辐射剂量,其应用是可行有效的；低kVp设置(100 kV)结合管电流调制技术仅对特定人群(体重指数＜24.9 kg/m2)具有减低辐射剂量的价值.
목적 탐토다층라선CT(MSCT)하지동맥성상중응용저관전압(kVp,100 kV)설치화관전류조제감저복사제량적가행성.방법 련속선취수행하지동맥조영적환자61례,안수궤수표수궤분위A조(120 kV)、B조(100 kV)、C조(100 kV+관전류조제).비교3조환자적도상객관평개지표、도상질량주관평분이급복사제량.C조진일보안체중지수(BMI)분위C1조(BMI ＜24.9kg/m2)급C2조(BMI≥24.9 kg/m2),비교2조환자간적복사제량.결과 3조환자적주-가부축위、용적재현(VR)、최대강도투영(MIP)도상적주관질량평분균재량호이상,차3조도상적신조비、대비조성비차이무통계학의의(P＞0.05).A、B、C3조적유효흡수제량분별위8.20、5.36화7.48mSv；B조교A조유효흡수제량감저약34.6％,C조교B조유효흡수제량증가약39.5％,차여A조비교차이무통계학의의(P＞0.05).C1조화C2조유효흡수제량위7.11화9.69 mSv,량조비교차이유통계학의의(t=-3.163,P＜0.05),C1조교C2조유효제량감저약26.6％.C1조교A조유효제량감저13.3％(Z=-2.822,P＜0.05),단교B조유효제량증가료32.6％(Z=-3.900,P＜0.05)；C2조교A조유효흡수제량증가18.2％ (P ＞0.05),교B조유효제량증가료80.8％(Z=-3.426,P＜0.05).결론 하지동맥MSCTA운용저kVp설치(100 kV)능재보증도상질량적동시강저복사제량,기응용시가행유효적；저kVp설치(100 kV)결합관전류조제기술부대특정인군(체중지수＜24.9 kg/m2)구유감저복사제량적개치.
Objective To study the feasibility of reducing radiation dose in aorto-iliac and lower extremity arteries CT angiography (CTA) with low tube voltage (100 kV) and automatic tube current modulation(ATCM).Methods Totally 61 patients requiting aorto-iliac and lower extremity arteries CTA for clinical reasons were prospectively enrolled in study.The patients were randomly assigned to 3 groups:Group A(120 kV),Group B (100 kV) and Group C (100 kV with automatic tube current modulation).Both quantitative and qualitative analysis were included in this research.Group C was divided into obese group(BMI≥ 24.9 kg/m2) and normal group(BMI ＜ 24.9 kg/m2).The radiation doses were analyzed respectively among two groups.Results The subjective evaluations of image quality for axial,MIP and VR were good.There were no significant differences among group A,B and C in SNR and CNR (P ＞0.05).The effective dose of group A,B and C was 8.20 mSv,5.36 mSv,and was 7.48 mSv,respectively Group B was 34.6％ less than group A.Group C was 39.5％ more than group B,and there was no significant differences between group A and C (P ＞ 0.05).The effective dose of group C1 was 7.11mSv,group C2 was 9.69 mSv,the E with group C1 were significantly less than group C2 (t =-3.163,P ＜0.05),the effective dose of group C1 was 13.3％ less than group A (Z =-2.822,P ＜ 0.05),but the group C2 was more than group A (P ＞ 0.05) and group B (Z =-3.426,P ＜ 0.05).Conclusions Lowkilovoltage (100 kV) CT scanning protocol is feasible in multi-detector CT angiography for aortoiliac and lower extremity arteries.Automatic low tube voltage (100 kV) with automatic tube current modulation (ATCM) scanning protocol can be used for someone with BMI less than 24.9 kg/m2.