基于调制传递函数的硬性内窥镜成像质量对比研究  

Study of Image Quality Comparison Based on the MTF Method Between Different Medical Rigid Endoscopes in an In Vitro Model

作　　者：王云龙[1,2] 姬军[1,2] 蒋昌松[3] 黄增跃[1,2] 

机构地区：[1]南方医科大学生物医学工程学院,广州510515 [2]解放军第三0五医院医学工程科,北京100017 [3]北京大学第三医院医学工程科,北京100191

出　　处：《生物医学工程学杂志》2015年第2期357-362,共6页Journal of Biomedical Engineering

基　　金：军事医学计量科研专项资助(2011-JL2-027);解放军第305医院科研基金资助项目(12YA2)

摘　　要：利用调制传递函数(MTF)对比三支Olympus硬性膀胱内窥镜成像质量。实验过程首先用三支不同型号膀胱镜(OLYMPUS视场角12°的膀胱尿道镜、OLYMPUS Germany A22003A和OLYMPUS A2013A)在不同光源强度下分别采集不同空间频率标靶的光栅图像,然后利用MTF在MALAB软件中处理采集图像得到膀胱镜在不同亮度下、不同空间频率中的MTF值,所得数据进行数学统计及成像质量对比分析。观察统计数据可知,三支内窥镜的MTF值均小于1;同一内窥镜在某一亮度下随着空间频率的增加MTF值逐步减小接近0;亮度增强的过程中同一内窥镜在同一空间频率下的MTF值有缓慢增加趋势;三支内窥镜MTF值完全不同,某些情况下MTF值相差较大,最大差值可以达到0.7。分析对比实验数据可得出结论,三支内窥镜成像质量不同。3号镜反差高而分辨率低;1号镜相反,分辨率高而反差低;2号镜的反差和分辨率都较高,成像质量最好。This study was aimed to use the method of modulation transfer function（MTF）to compare image quality among three different Olympus medical rigid cystoscopes in an in vitro model.During the experimental processes,we firstly used three different types of cystoscopes（i.e.OLYMPUS cystourethroscopy with FOV of 12°,OLYMPUS Germany A22003 Aand OLYMPUS A2013A）to collect raster images at different brightness with industrial camera and computer from the resolution target which is with different spatial frequency,and then we processed the collected images using MALAB software with the optical transfer function MTF to obtain the values of MTF at different brightness and different spatial frequency.We then did data mathematical statistics and compared imaging quality.The statistical data showed that all three MTF values were smaller than 1.MTF values with the spatial frequency gradually increasing would decrease approaching 0at the same brightness.When the brightness enhanced in the same process at the same spatial frequency,MTF values showed a slowly increasing trend.The three endoscopes＇ MTF values were completely different.In some cases the MTF values had a large difference,and the maximum difference could reach 0.7.Conclusion can be derived from analysis of experimental data that three Olympus medical rigid cystoscopes have completely different imaging quality abilities.The No.3endoscope OLYMPUS A2013 Ahas low resolution but high contrast.The No.1endoscope OLYMPUS cystourethroscopy with FOV of 12°,on the contrary,had high resolution and lower contrast.The No.2endoscope OLYMPUS Germany A22003 Ahad high contrast and high resolution,and its image quality was the best.

关 键 词：调制传递函数 成像质量 空间频率 光栅图像 

分 类 号：TH776[机械工程—仪器科学与技术] TP391.41[机械工程—精密仪器及机械]