CAJ | 학술논문

目的探讨腰椎数字X线摄影的后处理参数对影像质量的影响,从而在保证影像质量的同时降低有效辐射剂量.方法通过调节Philips DR系统工作站提供的后处理参数,对CDRAD2.0体模成像,在医用显示器上评价腰椎体模影像质量.运用析因实验设计,通过ANOVA方法总结出细节对比度增强(DCE)、噪声补偿(NC)、反锐化掩膜(UM)、反锐化掩膜核(UMK)等后处理参数的优化方案.根据Solidose剂量仪测量出的体模表面入射剂量(ESD),对方案的优化效果进行体模验证.结果通过析因实验显示,临床所用的管电压为70 kVp时,对影像质量影响较大的是DCE、UM和UMK(F值分别为91.45、373.79、429.88,P值均＜0.05).随着UM的增加(由0到5),图像质量因子(IQF)增加(约20个单位),而DCE和UMK增加导致IQF降低(分别约10和21个单位).增加管电压,IQF提高(如同样参数的设置下,管电压分别为63、85 kVp,IQF提高了14个单位),影像质量差异有统计学意义(t=5.31,P＜0.05).结论合理使用后处理参数的优化方案,可以在保证图像质量的前提下,通过增加管电压大大降低对患者的有效辐射剂量.
목적 탐토요추수자X선섭영적후처리삼수대영상질량적영향,종이재보증영상질량적동시강저유효복사제량.방법 통과조절Philips DR계통공작참제공적후처리삼수,대CDRAD2.0체모성상,재의용현시기상평개요추체모영상질량.운용석인실험설계,통과ANOVA방법총결출세절대비도증강(DCE)、조성보상(NC)、반예화엄막(UM)、반예화엄막핵(UMK)등후처리삼수적우화방안.근거Solidose제량의측량출적체모표면입사제량(ESD),대방안적우화효과진행체모험증.결과 통과석인실험현시,림상소용적관전압위70 kVp시,대영상질량영향교대적시DCE、UM화UMK(F치분별위91.45、373.79、429.88,P치균＜0.05).수착UM적증가(유0도5),도상질량인자(IQF)증가(약20개단위),이DCE화UMK증가도치IQF강저(분별약10화21개단위).증가관전압,IQF제고(여동양삼수적설치하,관전압분별위63、85 kVp,IQF제고료14개단위),영상질량차이유통계학의의(t=5.31,P＜0.05).결론합리사용후처리삼수적우화방안,가이재보증도상질량적전제하,통과증가관전압대대강저대환자적유효복사제량.
Objective To reduce the effective dose and maintain the image quality by adjusting the image processing parameters in the lumbar spine examinations.Methods This study investigated the influence of image processing parameters on image quality of Philips DR system by evaluating image quality of CDRAD 2.0 phantom.The parameters include detail contrast enhancement,noise compensation,unsharp masking and unsharp masking kernel.The entrance surface dose of phantom was measured by solidose meter.A synthetical parameters optimization project was proposed by analyzing the results of the investigation.This project was also testified by phantoms.Results Important effects were the main effects of DCE,unsharp masking and kernel at the clinically used tube potential of 70 kVp( F =91.45,373.79,429.88,P ＜ 0.05).These effects indicated an increase of the 1QF about 20 units with increasing unsharp masking,while an increase of DCE and kernel led to decrease of IQF about 10 and 21 units.When the tube potential was increased to 85 kV,keeping the settings of the process parameters unchanged,the IQF increased.The results showed statically significant difference ( t =5.31,P ＜ 0.05 ).Conclusion It is possible to lower the effective dose to the patient by the use of a higher tube potential and maintain a good image quality,and it will have little influence on clinic diagnosis through the most optimal setting of the process parameters.