CAJ | 학술논문

目的评价低剂量CT检查诊断肋骨骨折的可行性及图像质量.方法 25例胸部外伤行CT检查的患者,采用64层螺旋CT自动曝光控制技术,于吸气末屏气对整个胸廓以噪声指数(NI)11、21进行2次扫描,2次扫描的其他参数均保持一致.记录每次扫描的平均管电流、CT容积剂量指数(CTDIvol)和有效剂量(ED).由2名放射诊断医师埘每次扫描所见的肋骨骨折按Ⅰ、Ⅱ、Ⅲ度进行统计,以Wilcoxon配对符号秩和检验比较其差异;以5分制对图像诊断的接受率及主观噪声进行评价.采用Kappa-致性检验评价2名医师评定结果的一致性.结果 NI为11时,平均CTDIvol、ED分别为(13.88±5.17)mGy、(8.14 4-3.21)mSv;NI为21时,分别为(3.91±1.57)mGy、(2.31±0.97)mSv.NI为21的辐射剂量较NI为11者下降了72%.NI为11的平均管电流为(195.88±69.33)mAs、NI为21的平均管电流为(54.56±21.54)mAs.NI为21时扫描能检出NI为11时扫描所发现的全部Ⅱ度、Ⅲ度骨折及绝大部分Ⅰ度骨折.NI为11时骨窗的图像诊断接受率评分及主观噪声评分2名医师分别为(4.9±0.2)、(4.6±0.5)分;NI为21时平均为(3.5±0.5)、(3.3±0.5)分.2名医师对肋骨骨折的检出、图像诊断接受率及主观噪声的评定结果 Kappa值分别为0.876、0.820和0.792(P值均<0.01).结论 NI为21的低剂量CT扫描能满足临床对肋骨骨折诊断的要求.
목적 평개저제량CT검사진단륵골골절적가행성급도상질량.방법 25례흉부외상행CT검사적환자,채용64층라선CT자동폭광공제기술,우흡기말병기대정개흉곽이조성지수(NI)11、21진행2차소묘,2차소묘적기타삼수균보지일치.기록매차소묘적평균관전류、CT용적제량지수(CTDIvol)화유효제량(ED).유2명방사진단의사시매차소묘소견적륵골골절안Ⅰ、Ⅱ、Ⅲ도진행통계,이Wilcoxon배대부호질화검험비교기차이;이5분제대도상진단적접수솔급주관조성진행평개.채용Kappa-치성검험평개2명의사평정결과 적일치성.결과 NI위11시,평균CTDIvol、ED분별위(13.88±5.17)mGy、(8.14 4-3.21)mSv;NI위21시,분별위(3.91±1.57)mGy、(2.31±0.97)mSv.NI위21적복사제량교NI위11자하강료72%.NI위11적평균관전류위(195.88±69.33)mAs、NI위21적평균관전류위(54.56±21.54)mAs.NI위21시소묘능검출NI위11시소묘소발현적전부Ⅱ도、Ⅲ도골절급절대부분Ⅰ도골절.NI위11시골창적도상진단접수솔평분급주관조성평분2명의사분별위(4.9±0.2)、(4.6±0.5)분;NI위21시평균위(3.5±0.5)、(3.3±0.5)분.2명의사대륵골골절적검출、도상진단접수솔급주관조성적평정결과 Kappa치분별위0.876、0.820화0.792(P치균<0.01).결론 NI위21적저제량CT소묘능만족림상대륵골골절진단적요구.
Objective To evaluate images quality and diagnostic feasibility of low-dose CT in patients with traumatic rib fractures.Methods Twenty-five patients presented with thoracic iniury were underwent 64-slice spiral CT scanning in inspiration breath-hold technique.Two scan protocols were performed.In one scan protocol noise index(NI)is 11,and in another NI is 21,but the other scan parameters were no difference.The mean value of tube current,the volume CT dose index(CTDIvol),and effective dose(ED)were recorded.Image quality was scored by 2 experienced radiologists using the 5-points scale.The numbers and degrees of rib fractures were recorded.The data were tested by using the Wilcoxon signed rank sum test.The differences of the inter-observer were determined by Kappa statistics.Results The mean CTDIvol and ED in scan protocol with NI of 11 were(13.88±5.17)mGy and(8.14±3.21)mSv,and that with NI of 21 were(3.91±1.57)mGy and(2.31±0.97)mSv.Compared the scan with NI of 11.there was 72%intrinsie dose reduction in the scan with NI of 21.The mean value of tube current in scan with NI of 11 and 21 were(195.88±69.33)mAs and(54.56±21.54)mAs.AIl patients with 11 and Ⅲ degree and most patients with I degree rib fractures that identified by the scan with NT of 11 were detected by the scan with NI of 21.There were no statistical difference between two scaus with the Wilcoxon signed rank sum test.The diagnostic acceptability and image noise score in the scan with NI of 11 were 4.9±0.2 and 4.6±0.5.and that with NI=21 were 3.5±0.5 and 3.3±0.5.There was prefect concordante in the inter-observers in diagnostic acceptability on finding of rib fractures.diagnostic acceptability and image noise(Kappa=0.876,0.820,0.792,P<0.01)between two scan protocols.Conclusion Rib fractures can be diagnosed by the low-dose CT using the scan protocol with NI of 21.