CAJ | 학술논문

目的：探讨能谱CT对比剂追踪智能触发技术在低浓度等渗碘对比剂模式下支气管动脉成像的可行性。方法收集我院胸部增强患者20例，行能谱CT GSI扫描模式下支气管动脉血管成像（CTA）。经留置针注入碘克沙醇（270mgI/ml），剂量1．2ml/kg ，流速4．0 ml/s ，采用对比剂追踪智能法触发扫描。数据均传入工作站，通过GSI viewer软件获得混合能量图像（Quality Check ，QC ，140 kVp ）、最佳单能量图像，测定以上两组图像支气管动脉的CNR、SNR ，由两位有经验的放射科医师采用盲法对图像进行独立评分。支气管动脉CTA质量的主观评分采用配对 t检验，P ＜0．05具有统计学意义；评分一致性采用kappa检验。结果①本研究患者支气管动脉C T A图像在最佳单能量和混合能量组均显示共55支。最佳单能量组优质支气管动脉共46支（84％），平均主观评分：3．63±0．92；混合能量组优质支气管动脉共28支（51％），平均主观评分：2．57±0．90；两者具有明显统计学差异（ t＝13．608，P＜0．001）；两名医师评分结果具有较强一致性（ r ＝0．745， P ＜0．01）。最佳单能量组图像（C N R：35．1±21．23；S N R：45．10±23．32）C N R、S N R均明显优于140kVp混合能量组（CNR ：12．23±9．30；SNR：31．95±17．62）（ t ＝9．865，8．268，P ＜0．001）；②使用低浓度对比剂，患者碘对比剂的碘含量值均低于根据常规对比剂的每公斤体重测量值。结论采用低浓度碘对比剂可以在能谱CT 单能量技术优化条件下获得更多优质的支气管动脉图像，提高了支气管动脉的显示率和清晰度。
목적：탐토능보CT대비제추종지능촉발기술재저농도등삼전대비제모식하지기관동맥성상적가행성。방법수집아원흉부증강환자20례，행능보CT GSI소묘모식하지기관동맥혈관성상（CTA）。경류치침주입전극사순（270mgI/ml），제량1．2ml/kg ，류속4．0 ml/s ，채용대비제추종지능법촉발소묘。수거균전입공작참，통과GSI viewer연건획득혼합능량도상（Quality Check ，QC ，140 kVp ）、최가단능량도상，측정이상량조도상지기관동맥적CNR、SNR ，유량위유경험적방사과의사채용맹법대도상진행독립평분。지기관동맥CTA질량적주관평분채용배대 t검험，P ＜0．05구유통계학의의；평분일치성채용kappa검험。결과①본연구환자지기관동맥C T A도상재최가단능량화혼합능량조균현시공55지。최가단능량조우질지기관동맥공46지（84％），평균주관평분：3．63±0．92；혼합능량조우질지기관동맥공28지（51％），평균주관평분：2．57±0．90；량자구유명현통계학차이（ t＝13．608，P＜0．001）；량명의사평분결과구유교강일치성（ r ＝0．745， P ＜0．01）。최가단능량조도상（C N R：35．1±21．23；S N R：45．10±23．32）C N R、S N R균명현우우140kVp혼합능량조（CNR ：12．23±9．30；SNR：31．95±17．62）（ t ＝9．865，8．268，P ＜0．001）；②사용저농도대비제，환자전대비제적전함량치균저우근거상규대비제적매공근체중측량치。결론채용저농도전대비제가이재능보CT 단능량기술우화조건하획득경다우질적지기관동맥도상，제고료지기관동맥적현시솔화청석도。
Objective To investigate the feasibility of spectral CT imaging in angiography of bronchial artery with low concentration of iodine contrast agent .Methods 20 patients in our hospital consecutively underwent enhanced chest CT scan on GSI mode (Discovery CT750 HD ,GE healthcare) .The injection parameters were 1 .2 ml/kg of injection volume , and 4 .0 ml/s of injection speed with iodixanol (270 mgI/ml) .SmartPrep was used to trigger the scan .The source images were conveyed to AW 4 .5 workstation and optimal keV images were obtained by GSI viewer software .We compared 140 kVp QC images (Quality Check) and the optimal keV images after measuring CT value and SD value ,and calculated CNR and SNR of bronchial artery on each patient .5-point scale was used to compare the image quality by 2 experienced radiolo-gists independent and blinded .Results The mean CT value ,mean CNR and mean SNR of the optimal keV images (HU :269 .22 ± 77 .23 ;CNR:35 .1 ± 21 .23 ;SNR :45 .10 ± 23 .32) were statistically higher than those in QC images (HU :160.53 ± 45 .74 ;CNR:12 .23 ± 9 .30;SNR:31 .95 ± 17 .62) ( t =17 .823 ,9 .865 ,8 .268 ,P <0 .001) .The subjective score in the optimal keV images (3 .63 ± 0 .92) was higher than that of QC images (2 .57 ± 0 .90) ,( t =13 .608 ,P <0.001) .Totally ;55 bronchial arteries were involved in the study .46 (84% ) of them in optimal keV group met the best quality imaging ,but only 28 (51% ) bronchial artery of QC images met .There was a strong correlation between two phy-sicians (kappa=0.745 ,P <0 .01) .Conclusion Low concentration of contrast agent combined with spectral CT imaging gets acceptable image quality in CTA of bronchial artery ,which can reduce contrast agent does in different degrees .