滤波反投影的冠状动脉CTA低剂量优化方案初探  

The optimized study of low-dose coronary CTA with filtered back projection

作　　者：黄海波[1] 黄桂雄[1] 林莹[1] 管俊[1] 曾嵩[1] 

机构地区：[1]解放军第303医院医学影像科,南宁530021

出　　处：《中华临床医师杂志（电子版）》2014年第12期29-33,共5页Chinese Journal of Clinicians(Electronic Edition)

摘　　要：目的探讨滤波反投影(FBP)的冠状动脉CT血管成像(CCTA)低剂量优化方案。方法 100例CCTA检查者编入A、B、C三组。A组采用回顾性心电门控、螺旋模式、120 kVp作为对照组;研究组B采用回顾性心电门控、螺旋模式、100 kVp同时适应增加管电流;研究组C使用前瞻性心电门控、轴扫模式。由两名经验丰富放射科医师双盲法操作完成,记录性别、年龄、BMI、心率(HR)、对比剂量(VOCA)、Z轴扫描长度(LZA)、CT容积剂量指数(CTDIvol)、剂量长度乘积(DLP)、有效辐射剂量(ED),测量和记录主动脉根部(ROA)CT值及噪声指数(IN)、图像主观质量评分(Score)、冠状动脉节段数(Seg.)及其分布,比较三组间上述变量差异。结果两医师评分一致性较好,Kappa值为0.62;三组间性别、年龄、BMI、HR、VOCA、LZA、Score差异无统计学意义(P>0.05),可诊断冠状动脉节段数98.97%(1 149/1 161),三组间各分值冠状动脉节段分布无统计学差异(P>0.05);三组间ROA、IN差异有统计学意义,多重比较显示除A与C组间ROA、A与B组间IN无统计学差异(P>0.05)外均有统计学意义(P<0.05);三组间CTDIvol、DLP、ED差异有统计学意义(P<0.05),多重比较显示CTDIvol、DLP、ED差异在各组之间均有统计学意义(P=0.000),与A组比较,B组CTDIvol、DLP、ED分别减少25.3%、30.1%、30.1%,C组CTDIvol、DLP、ED减少56.1%、70.2%、70.2%;与B组比较,C组CTDIvol、DLP、ED分别减少41.2%、57.3%、57.3%。结论采用FBP的256 iCT冠状动脉优化方案减少了辐射剂量,后门控在降低管电压并适当增加曝光量时可使ED减少约30.1%,前门控扫描较常规后门控减少ED约70.2%。ObjectiveTo explore the optimized program of low-doseCCTA with filtered back projection（FBP）. Methods 100 cases on 256-slices CCTA were recruited and splited into the control group A, studying Group B and C randomly. Scanning condition were as follows： Group A 120 Kv, automatic smart mA（about 800 mA）, using retrospective ECG-gating with HELIX; Group B 100 Kv, automatic smart mA（about 900-1 200 mA）, using retrospective ECG-gating with HELIX; Group C 120 Kvp, automatic smart mA（about 225-285 mA）, using prospective ECG-gating with Axis scanning. Two radiologists completed all procedures in blind manner. Record patient＇s Sex, Age, BMI, HR, VOCA, LZA, CTDIvol, DLP, ED, ROA, IN, Score, Seg. and its distribution, then compared their difference of variables above among three groups. ResultsSubjective score consistency was achieved（Kappa value, 0.62）. There was no statistical significance in Sex, Age, BMI, VOCA, LZA, score, seg. and its distribution amongst the groups （P＆gt;0.05）, the percentage of diagnostic segments was 98.97% （1 149/1 161）. There＆amp;nbsp;was statistical significance in ROA, IN, CTDIvol, DLP, ED among the groups （P〈0.05）. Compared with Group A, CTDIvol, DLP, ED from Group B decreased by 25.3% 30.1% 30.1% respectively, CTDIvol DLP ED from Group C decreased by 56.1% 70.2% 70.2% respectively; Compared with group B, CTDIvol DLP ED from Group C decreased by 41.2% 57.3% 57.3% respectively.Conclusions CCTA based on FBP could reduced radiation dose by optimized program on 256iCT. ED could be reduced by 70.2% using prospective ECG-gated technique compared with retrospective ECG-gated one. ED could be reduced by 30.1% while lower voltage and increase exposure using retrospective ECG-gated. Therefore, there was a certain value of clinical before a new reconstructive software was fixed in equipment.

关 键 词：冠状血管造影术 滤波反投影 低剂量 优化方案 

分 类 号：R816.2[医药卫生—放射医学]