Generation of Digital Reconstruction Radiation Image and Display System Design

Digitally reconstructed radiography (DRR) plays an important role in the treatment planning system (TPS) and many medical imaging applications such as 2D / 3D image registration. DRR generation technology is one of the core technologies of TPS. In this paper, the DRR image is generated by ray projection method based on volume rendering, and the display interface is designed to visualize the results. The medical image data set is resampled by reading the file header information of the medical image data set and the simulated light source projection distance, data set image spacing and pixel size are calculated by establishing the relevant coordinate transformation function and interpolation function. Finally, the DRR image results are displayed on the interface designed by the QT framework. The similarity is measured between the DRR image generated by ray casting method and the DRR image obtained by clinical TPS. The average of root mean square error(RMSE) is 0.25,and the peak signal-to-noise ratio(PSNR) is greater than 30 decibels and the structural similarity image measurement(SSIM) is positive. The results can provide the core technology for the subsequent DRR image display system and 2D / 3D registration. As well, the display interface can normally display the three orthographic views and DRR results of CT sequence images. It can be seen that the DRR image generated by the algorithm used in this paper has the same quality as the DRR image in clinical application, which proves the effectiveness of the algorithm and the good imaging effect.