基于ImageJ的伽马刀质量控制检测技术的应用研究

Applied research of Gamma knife detecting technique based on ImageJ

目的:基于ImageJ图像处理软件,制定一套实用性强、准确可靠的γ刀检测分析方法,以解决γ刀检测中的胶片分析问题。方法:利用ImageJ图像处理软件,并结合宏命令(macro)编写脚本程序,对γ刀检测的胶片图像进行分析,分别实现胶片剂量标定、机械等中心与辐射野等中心的偏差、照射野尺寸、半影宽度等关键参数的分析与计算。结果:胶片剂量标定中,用不同的拟合函数建立胶片的灰度-剂量曲线,对于EBT3胶片,多项式拟合和Devic方法均能取得可接受的拟合结果,相关系数r^(2)>0.99;利用图像处理方法对等中心偏差的结果进行了验证,偏差≤0.05 mm;辐射野尺寸和半影宽度的计算结果与γ刀厂家的分析软件得到的结果具有较好一致性,二者偏差<1 mm。结论:制定的γ刀检测分析方法可为γ刀质量控制检测工作提供技术支撑,提高检测结果的准确性与可靠性。

Objective:To establish a Gamma knife detecting analysis method with strong practicability,accuracy and reliability based on ImageJ image processing software so as to resolve the problem of film analysis in the detection with Gamma knife.Methods:Using ImageJ image processing software,and combining with macro command to compile script program.And the file image with the detection of Gamma knife were further analyzed.And then,the analyses and calculations of calibration of film dosage,the deviation between the isocenter of machine and the isocenter of radiation field,the size of radiation field,penumbra width and other key parameters were respectively realized.Results:In the calibration of film dose,the different fitting functions were used to establish the gray-dose curve of film.For EBT3 film,both polynomial fitting and DEVIC method could obtain acceptable fitting results(correlation coefficient r^(2)>0.99).The deviation results of isocenter were verified by using image processing method,and the deviation was less than and equal to 0.05 mm.There was favorable consistency between the calculated result of the size of radiation field and the penumbra width and the analysis software of Gamma knife manufacturer,and the deviation of the them was less than 1mm.Conclusion:The formulated Gamma knife detection method can provide technique support for the detection work of quality control of Gamma knife,and improve the accuracy and reliability of the detected results.