基于DRR图像的膀胱径线与体积相关性研究

Investigate the Correlation of Volume and Radial Direction Distance of Bladder for Cervical Cancer in Digitally Reconstructed Radiography

目的研究在数字影像重建(digitally reconstructed radiography,DRR)图像中宫颈癌膀胱径线与膀胱体积的相关性。方法选取2016年8月至2017年6月期间32例进行放射治疗的宫颈癌患者。把放射治疗前的CT定位图像传至雷泰计划系统中勾画出膀胱轮廓并计算出膀胱的体积。同时生成0°机架角度下的DRR图像。在DRR图像中测量膀胱的水平径线长度和垂直径线长度。用SPSS16.0统计软件分析膀胱体积与其水平径线、垂直径线、水平及垂直径线长度的乘积的相关性。结果膀胱体积与其水平径线、垂直径线、水平及垂直径线长度的乘积的相关性分别为0.75、0.83、0.87(P<0.001)。结论在DRR图像中,测量膀胱的水平和垂直径线的乘积与膀胱体积有很强的相关性。可以利用测量的径线的乘积来监测膀胱的充盈程度。

Objective To analyze the correlation of volume and radial direction distance of bladder for cervical cancer in digitally reconstructed radiography（DRR）. Methods 32 cervical cancer patients were enrolled in this study from August 2016 to June 2017.The planning CT images were transferred to treatment planning system of Leitai. All bladders were contoured and calculated the volumes. The distances of level and vertical for bladder were measured in DRR. In SPSS, the correlation of distance and volume were analyzed. Results The correlation coefficients for volume vs level distance, volume vs vertical distance, volume vs the product of level and vertical distance for bladder were 0.75,0.83,0.87（P〈0.001）, respectively. Conclusion In DRR images, the correlation for volume vs the product of level and vertical distance for bladder is high. The the product of level and vertical distance for bladder can evaluate the filling status of bladder.