中华放射学杂志
中華放射學雜誌
중화방사학잡지
Chinese Journal of Radiology
2010年
7期
731-734
,共4页
杨瑞%代立梅%李剑颖%王凤艳%杜国权
楊瑞%代立梅%李劍穎%王鳳豔%杜國權
양서%대립매%리검영%왕봉염%두국권
眼眶%辐射剂量%体层摄影术,X线计算机
眼眶%輻射劑量%體層攝影術,X線計算機
안광%복사제량%체층섭영술,X선계산궤
Orbit%Radiation dosage%Tomography,X-ray computed
目的 探讨眼眶部外伤检查时MSCT扫描的最适低剂量.方法 选择30例眶壁骨折患者的横轴面骨折层面影像,通过图像空间添加噪声软件模拟出30、70、100、140、170、200 mA 6种低剂量影像,根据影像质量及骨折等显示情况进行评价,找出满足诊断需求的最适球管电流量后进行临床应用.同时记录容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP)、有效剂量(ED).影像质量按影像层次、噪声、解剖结构及能否满足诊断要求的显示情况而采用好、较好、一般、差、很差的5级制评价.等级资料使用秩和检验进行统计分析,计数资料采用X2检验.结果 在使用常规剂量300 mA扫描条件时30例眼眶外伤患者图像中显示眶骨骨折30例、眶内气肿19例、眼肌损伤12例、眶内异物1例.在低剂最模拟图像中,不同剂量的图像质量差异有统计学意义(X2=102.009,P=0.000).当剂量降低至70 mA时上述所有临床征象仍可清晰显示和准确诊断,但图像质量评价为好1例、较好8例、一般21例,无差及很差.当模拟剂量管电流降低至100 mA时,图像质量评价为好9例、较好17例、一般4例,无差及很差;且同常规剂量差异无统计学意义(P>0.05).临床实际应用100 mA管电流检查20例眼眶外伤患者,所得图像质量为好5例、较好13例、一般2例,无差及很差.CTDIvol、DLP、ED分别为20.84 mGy、125.04 mGy·cm、0.29 mSv.与常规剂量(300 mA)CTDIvol、DLP、ED分别为62.53 mGy、375.18 mGy·cm、0.86 mSv,比较管电流100 mA进行扫描时,ED下降了70%.结论 眼眶部外伤进行MSCT扫描时,管电流为100 mA所得图像即可满足临床诊断要求,又可明显降低对患者的辐射剂量.
目的 探討眼眶部外傷檢查時MSCT掃描的最適低劑量.方法 選擇30例眶壁骨摺患者的橫軸麵骨摺層麵影像,通過圖像空間添加譟聲軟件模擬齣30、70、100、140、170、200 mA 6種低劑量影像,根據影像質量及骨摺等顯示情況進行評價,找齣滿足診斷需求的最適毬管電流量後進行臨床應用.同時記錄容積CT劑量指數(CTDIvol)、劑量長度乘積(DLP)、有效劑量(ED).影像質量按影像層次、譟聲、解剖結構及能否滿足診斷要求的顯示情況而採用好、較好、一般、差、很差的5級製評價.等級資料使用秩和檢驗進行統計分析,計數資料採用X2檢驗.結果 在使用常規劑量300 mA掃描條件時30例眼眶外傷患者圖像中顯示眶骨骨摺30例、眶內氣腫19例、眼肌損傷12例、眶內異物1例.在低劑最模擬圖像中,不同劑量的圖像質量差異有統計學意義(X2=102.009,P=0.000).噹劑量降低至70 mA時上述所有臨床徵象仍可清晰顯示和準確診斷,但圖像質量評價為好1例、較好8例、一般21例,無差及很差.噹模擬劑量管電流降低至100 mA時,圖像質量評價為好9例、較好17例、一般4例,無差及很差;且同常規劑量差異無統計學意義(P>0.05).臨床實際應用100 mA管電流檢查20例眼眶外傷患者,所得圖像質量為好5例、較好13例、一般2例,無差及很差.CTDIvol、DLP、ED分彆為20.84 mGy、125.04 mGy·cm、0.29 mSv.與常規劑量(300 mA)CTDIvol、DLP、ED分彆為62.53 mGy、375.18 mGy·cm、0.86 mSv,比較管電流100 mA進行掃描時,ED下降瞭70%.結論 眼眶部外傷進行MSCT掃描時,管電流為100 mA所得圖像即可滿足臨床診斷要求,又可明顯降低對患者的輻射劑量.
목적 탐토안광부외상검사시MSCT소묘적최괄저제량.방법 선택30례광벽골절환자적횡축면골절층면영상,통과도상공간첨가조성연건모의출30、70、100、140、170、200 mA 6충저제량영상,근거영상질량급골절등현시정황진행평개,조출만족진단수구적최괄구관전류량후진행림상응용.동시기록용적CT제량지수(CTDIvol)、제량장도승적(DLP)、유효제량(ED).영상질량안영상층차、조성、해부결구급능부만족진단요구적현시정황이채용호、교호、일반、차、흔차적5급제평개.등급자료사용질화검험진행통계분석,계수자료채용X2검험.결과 재사용상규제량300 mA소묘조건시30례안광외상환자도상중현시광골골절30례、광내기종19례、안기손상12례、광내이물1례.재저제최모의도상중,불동제량적도상질량차이유통계학의의(X2=102.009,P=0.000).당제량강저지70 mA시상술소유림상정상잉가청석현시화준학진단,단도상질량평개위호1례、교호8례、일반21례,무차급흔차.당모의제량관전류강저지100 mA시,도상질량평개위호9례、교호17례、일반4례,무차급흔차;차동상규제량차이무통계학의의(P>0.05).림상실제응용100 mA관전류검사20례안광외상환자,소득도상질량위호5례、교호13례、일반2례,무차급흔차.CTDIvol、DLP、ED분별위20.84 mGy、125.04 mGy·cm、0.29 mSv.여상규제량(300 mA)CTDIvol、DLP、ED분별위62.53 mGy、375.18 mGy·cm、0.86 mSv,비교관전류100 mA진행소묘시,ED하강료70%.결론 안광부외상진행MSCT소묘시,관전류위100 mA소득도상즉가만족림상진단요구,우가명현강저대환자적복사제량.
Objective To investigate the most appropriate low radiation dose in multi-slice CT (MSCT) scans for orbital trauma patients. Methods Thirty trauma patients with suspected orbital fractures who underwent helical CT scans with a 64-MSCT using regular dose were selected. Noise was artificially introduced to the axial images using an image space noise addition tool to simulate 6 sets of lower dose scans with tube current of 30, 70, 100, 140, 170 and 200 mA, respectively. The lowest tube current with adequate image quality for confident diagnosis was determined based on the evaluation of the overall image quality and fracture detection on images at different dose levels. The determined lowest tube current was then validated using clinical scans. Radiation dose related parameters CTDIvol, DLP, ED were also recorded.Image quality was evaluated according to its low-density resolution, noise and structure clarity and characterized into 5-grades of excellent, good, fair, worse and worst Rank sum test and X2 test were wsed for statistics. Results In 30 trauma patients with regular dose of 300 mA, there were 30 cases of orbital fracture, 19 cases of intraorbital emphysema, 12 cases of ocular muscle injury and 1 case of intraorbital foreign body. These changes could still be clearly observed and correctly diagnosed when the tube current was reduced to as low as 70 mA. However, the overall image quality was mostly fair. At the simulated dose of 100 mA, the majority of images were characterized as excellent or good, and there was no statistical difference compared with that of regular dose scans (P > 0.05 ) . In the clinical evaluation for 20 orbital trauma patients with the reduced tube current of 100 mA, the majority of images were judged to be excellent (9 cases) or good(17 cases) and fair (4 cases). The radiation dose(0. 29 mSv) was reduced by 70% compared with that of regular tube current of 300 mA(0. 86 mSv). Conclusion The tube current of MSCT may be used as low as 100 mA in orbital trauma patients to reduce radiation dose and keep the image quality diagnosable.
