中华放射学杂志
中華放射學雜誌
중화방사학잡지
Chinese Journal of Radiology
2012年
5期
416-419
,共4页
肺栓塞%体层摄影术,X线计算机%血管造影术%图像增强
肺栓塞%體層攝影術,X線計算機%血管造影術%圖像增彊
폐전새%체층섭영술,X선계산궤%혈관조영술%도상증강
Pulmonary embolism%Tomography,X-ray computed%Angiography%Image enhancement
目的 推导CT肺动脉成像(CTPA)中精确计算对比剂用量公式,并评价其应用于小剂量对比剂预注射法CTPA影像的质量与临床应用的意义.方法 搜集经CTPA检查的连续27例患者小剂量对比剂实验注射形成的TDC数据,分析从注射对比剂开始至上腔静脉下端增强峰值所用时间占注射开始至肺动脉增强峰值时间的比值,测算上腔静脉下端在扫描范围中的水平,推导出计算对比剂使用总量预计算公式( DTs/3+ STs/2).将临床怀疑但CTPA未发现为肺动脉栓塞(PE)的68例患者纳入研究,按检查奇、偶周数分为2组:A组26例,传统增强跟踪自动触发扫描组；B组42例,小剂量对比剂预注射组.在CTPA影像中,2组分别测量右肺动脉主干(RMPA)和右上肺静脉(RUPV)、右肺下叶后基底段动脉(RLPA)和伴行右下肺静脉(RLPV)、RMPA与升主动脉(AA)的CT值,计算每对血管CT值差值,对影像进行评分,并计算对比剂用量、上腔静脉内对比剂硬化伪影分级.采用f检验、x2检验与秩和U检验,分析2组间各值差异的统计学意义.结果 对比剂开始至注射到上腔静脉增强时间与至肺动脉增强时间比为0.65±0.09.A、B2组间RMPA、RLPA的CT值分别为(301±117)、(329±122)与(283±95)、(277±98)HU,差异无统计学意义(t值分别为1.060、2.056,P值均＞0.05),但肺动静脉血管对之间的CT值差(中位数分别为22.5、58.0与170.5、166.5 HU),2组间差异有统计学意义(U=292,P=0.001与U=325,P=0.005)；影像评分为5分与4分者B组为85.7％( 36/42)优于A组(46.1％,12/26),差异有统计学意义(x2=14.175,P＜0.01)；上腔静脉内对比剂伪影分级(1～3级)B组(分别为34、7、1例)明显好于A组(分别为11、10、5例),差异有统计学意义(x2=10.714,P=0.002);对比剂实际注射总量A组为(87.6±7.3)ml,B组为(40.0±5.4) ml,差异有统计学意义(t=-2.152,P＜0.01).结论 采用小剂量对比剂预注射法与传统方法比较,CTPA影像质量与强化程度一致,但可明显降低肺静脉内对比剂的浓度,对肺动脉的辨识更容易,而且可明显减少上腔静脉内对比剂的硬化伪影对右肺动脉观察的干扰,降低对比剂的用量,有利于减轻患者对比剂肾病的危险.
目的 推導CT肺動脈成像(CTPA)中精確計算對比劑用量公式,併評價其應用于小劑量對比劑預註射法CTPA影像的質量與臨床應用的意義.方法 搜集經CTPA檢查的連續27例患者小劑量對比劑實驗註射形成的TDC數據,分析從註射對比劑開始至上腔靜脈下耑增彊峰值所用時間佔註射開始至肺動脈增彊峰值時間的比值,測算上腔靜脈下耑在掃描範圍中的水平,推導齣計算對比劑使用總量預計算公式( DTs/3+ STs/2).將臨床懷疑但CTPA未髮現為肺動脈栓塞(PE)的68例患者納入研究,按檢查奇、偶週數分為2組:A組26例,傳統增彊跟蹤自動觸髮掃描組；B組42例,小劑量對比劑預註射組.在CTPA影像中,2組分彆測量右肺動脈主榦(RMPA)和右上肺靜脈(RUPV)、右肺下葉後基底段動脈(RLPA)和伴行右下肺靜脈(RLPV)、RMPA與升主動脈(AA)的CT值,計算每對血管CT值差值,對影像進行評分,併計算對比劑用量、上腔靜脈內對比劑硬化偽影分級.採用f檢驗、x2檢驗與秩和U檢驗,分析2組間各值差異的統計學意義.結果 對比劑開始至註射到上腔靜脈增彊時間與至肺動脈增彊時間比為0.65±0.09.A、B2組間RMPA、RLPA的CT值分彆為(301±117)、(329±122)與(283±95)、(277±98)HU,差異無統計學意義(t值分彆為1.060、2.056,P值均＞0.05),但肺動靜脈血管對之間的CT值差(中位數分彆為22.5、58.0與170.5、166.5 HU),2組間差異有統計學意義(U=292,P=0.001與U=325,P=0.005)；影像評分為5分與4分者B組為85.7％( 36/42)優于A組(46.1％,12/26),差異有統計學意義(x2=14.175,P＜0.01)；上腔靜脈內對比劑偽影分級(1～3級)B組(分彆為34、7、1例)明顯好于A組(分彆為11、10、5例),差異有統計學意義(x2=10.714,P=0.002);對比劑實際註射總量A組為(87.6±7.3)ml,B組為(40.0±5.4) ml,差異有統計學意義(t=-2.152,P＜0.01).結論 採用小劑量對比劑預註射法與傳統方法比較,CTPA影像質量與彊化程度一緻,但可明顯降低肺靜脈內對比劑的濃度,對肺動脈的辨識更容易,而且可明顯減少上腔靜脈內對比劑的硬化偽影對右肺動脈觀察的榦擾,降低對比劑的用量,有利于減輕患者對比劑腎病的危險.
목적 추도CT폐동맥성상(CTPA)중정학계산대비제용량공식,병평개기응용우소제량대비제예주사법CTPA영상적질량여림상응용적의의.방법 수집경CTPA검사적련속27례환자소제량대비제실험주사형성적TDC수거,분석종주사대비제개시지상강정맥하단증강봉치소용시간점주사개시지폐동맥증강봉치시간적비치,측산상강정맥하단재소묘범위중적수평,추도출계산대비제사용총량예계산공식( DTs/3+ STs/2).장림상부의단CTPA미발현위폐동맥전새(PE)적68례환자납입연구,안검사기、우주수분위2조:A조26례,전통증강근종자동촉발소묘조；B조42례,소제량대비제예주사조.재CTPA영상중,2조분별측량우폐동맥주간(RMPA)화우상폐정맥(RUPV)、우폐하협후기저단동맥(RLPA)화반행우하폐정맥(RLPV)、RMPA여승주동맥(AA)적CT치,계산매대혈관CT치차치,대영상진행평분,병계산대비제용량、상강정맥내대비제경화위영분급.채용f검험、x2검험여질화U검험,분석2조간각치차이적통계학의의.결과 대비제개시지주사도상강정맥증강시간여지폐동맥증강시간비위0.65±0.09.A、B2조간RMPA、RLPA적CT치분별위(301±117)、(329±122)여(283±95)、(277±98)HU,차이무통계학의의(t치분별위1.060、2.056,P치균＞0.05),단폐동정맥혈관대지간적CT치차(중위수분별위22.5、58.0여170.5、166.5 HU),2조간차이유통계학의의(U=292,P=0.001여U=325,P=0.005)；영상평분위5분여4분자B조위85.7％( 36/42)우우A조(46.1％,12/26),차이유통계학의의(x2=14.175,P＜0.01)；상강정맥내대비제위영분급(1～3급)B조(분별위34、7、1례)명현호우A조(분별위11、10、5례),차이유통계학의의(x2=10.714,P=0.002);대비제실제주사총량A조위(87.6±7.3)ml,B조위(40.0±5.4) ml,차이유통계학의의(t=-2.152,P＜0.01).결론 채용소제량대비제예주사법여전통방법비교,CTPA영상질량여강화정도일치,단가명현강저폐정맥내대비제적농도,대폐동맥적변식경용역,이차가명현감소상강정맥내대비제적경화위영대우폐동맥관찰적간우,강저대비제적용량,유리우감경환자대비제신병적위험.
Objective To derive and evaluate the formula of exactly calculating the contrast dosage used during pulmonary CT angiography ( CTPA ). Methods Time density curves in 27 patients who underwent CTPA were collected and analyzed,the formula for calculating contrast dosage during CTPA was derived.68 patients suspected of pulmonary embolism ( PE ) clinically but no PE on CTPA were divided randomly into group A,with bolus tracing technique ( n =26 ),and group B,with small dose injection contrast test (SDCT) (n =42).The CT values of the right main pulmonary artery (RMPA),right upper pulmonary vein ( RUPV),right posterior basal PA,right lower PV (RLPV) and the aorta were calculated.The total contrast dosage and the hard beam artifact in the SVC were compared between the two groups.Student's t test,Chi-square test and Mann-Whitney U test were used.Results The ratio of the time from starting injection to enhancement peak of caudal end of SVC and the time to enhancement peak of the main pulmonary trunk was 0.65 ±0.09 (about 2/3),the formula for contrast dosage calculation was derived as (DTs/3 + STs/2) FR ml/s.The CT values of RMPA and RLPA between the two groups[ (301 ±117),(329 ± 122) and (283 ±95),(277 ±98) HU respectively] were not significantly different (t =1.060,P =0.292 ;t =2.056,P =0.044),but the differences of CT values in the paired PA and PV between the two groups (median were 22.5,58.0 and 170.5,166.5 HU respectively ) were significant (U =292,P =0.001 and U =325,P =0.005),contrast artifact of the SVC (grade 1-3) in group B ( n =34,7,1 respectively) was significantly less than in group A (n =11,10,5 respectively,x2 =10.714,P =0.002),the contrast dosage injected in group A was ( 87.6 ± 7.3 ) ml,and in group B was ( 40.0 ±5.4) ml (P ＜0.01 ).Conclusion CTPA with SDCT technique is superior to that with conventional bolus tracing technique regarding contrast dosage and contrast artifact in the SVC.
