中华放射医学与防护杂志
中華放射醫學與防護雜誌
중화방사의학여방호잡지
Chinese Journal of Radiological Medicine and Protection
2014年
5期
390-393
,共4页
鼻窦%体层摄影术,X射线计算机%迭代重建%辐射剂量
鼻竇%體層攝影術,X射線計算機%迭代重建%輻射劑量
비두%체층섭영술,X사선계산궤%질대중건%복사제량
Paranasal sinus%Tomography,X-ray computed%Iterative reconstruction%Radiation dose
目的 探讨鼻窦多层CT(MSCT)检查中应用迭代算法(iDose算法)对图像质量及辐射剂量的影响.方法 选取53例鼻窦图像,计算其平均对比噪声比(CNR),以此值为基准选择合适的离体头颅标本作为研究对象.改变扫描参数(kV及有效mAs),分别使用滤波反投影算法(FBP)和迭代算法(iDose等级1～7)重建图像,对图像质量进行主、客观评价,找出可以符合诊断需求的参数组合.结果 冠状位图像的CNR高于水平位图像(t=-6.86,P＜0.05).120 kV、100 mAs/层、iDose5算法与常规扫描参数FBP算法所得图像CNR相当;100 kV、60 mAs/层、iDose4算法所得图像可满足对炎症的诊断,100 kV、80 mAs/层、iDose4算法所得图像可同时满足对炎症和外伤骨折的诊断,有效剂量可分别降低82％和75％.结论 使用iDose算法对鼻窦炎症及骨折的诊断,可以在保证满足诊断要求的前提下降低有效剂量.
目的 探討鼻竇多層CT(MSCT)檢查中應用迭代算法(iDose算法)對圖像質量及輻射劑量的影響.方法 選取53例鼻竇圖像,計算其平均對比譟聲比(CNR),以此值為基準選擇閤適的離體頭顱標本作為研究對象.改變掃描參數(kV及有效mAs),分彆使用濾波反投影算法(FBP)和迭代算法(iDose等級1～7)重建圖像,對圖像質量進行主、客觀評價,找齣可以符閤診斷需求的參數組閤.結果 冠狀位圖像的CNR高于水平位圖像(t=-6.86,P＜0.05).120 kV、100 mAs/層、iDose5算法與常規掃描參數FBP算法所得圖像CNR相噹;100 kV、60 mAs/層、iDose4算法所得圖像可滿足對炎癥的診斷,100 kV、80 mAs/層、iDose4算法所得圖像可同時滿足對炎癥和外傷骨摺的診斷,有效劑量可分彆降低82％和75％.結論 使用iDose算法對鼻竇炎癥及骨摺的診斷,可以在保證滿足診斷要求的前提下降低有效劑量.
목적 탐토비두다층CT(MSCT)검사중응용질대산법(iDose산법)대도상질량급복사제량적영향.방법 선취53례비두도상,계산기평균대비조성비(CNR),이차치위기준선택합괄적리체두로표본작위연구대상.개변소묘삼수(kV급유효mAs),분별사용려파반투영산법(FBP)화질대산법(iDose등급1～7)중건도상,대도상질량진행주、객관평개,조출가이부합진단수구적삼수조합.결과 관상위도상적CNR고우수평위도상(t=-6.86,P＜0.05).120 kV、100 mAs/층、iDose5산법여상규소묘삼수FBP산법소득도상CNR상당;100 kV、60 mAs/층、iDose4산법소득도상가만족대염증적진단,100 kV、80 mAs/층、iDose4산법소득도상가동시만족대염증화외상골절적진단,유효제량가분별강저82％화75％.결론 사용iDose산법대비두염증급골절적진단,가이재보증만족진단요구적전제하강저유효제량.
Objective To study the effect of iterative algorithm (iDose algorithm) on image quality and radiation dose in paranasal sinus MSCT.Methods A proper cadaveric head based on the average CNR (contrast noise ratio) of paranasal sinus images in 53 patients was applied.The cadaveric head was scanned with different parameters of kV and effective mAs.The images were reconstructed with filtered back projection and iterative algorithm (iDose 1-7) respectively.The subjective and objective evaluations were performed for all the images and the optimal parameter combination was found out.Results The CNR of coronal images was slightly higher than that of axial images (t =-6.86,P ＜0.05).The image CNR of protocol (120 kV,100 mAs/slice and iDose5) was close to that of conventional protocol.The protocol of 100 kV,60 mAs/slice and iDose4 offered the images adaptable for diagnosis of inflammation.The protocol of 100 kV,80 mAs/slice and iDose4 offered the images adaptable for diagnosis of inflammation and fracture,and the radiation dose were reduced by 82％ and 75％,respectively.Conclusions Using the iDose algorithm could help to offer diagnostic images for inflammation and fracture and reduce the radiation dose in the paranasal sinus MSCT.
