Application of Wiener Filter Computed Radiography (CR) Technique to Eliminate Noise (Denoising) of Image Quality and Anatomy in Verification Geometric Radiotherapy

Abstract

The success of radiotherapy irradiation is very dependent on geometric verification, as for the geometric verification that is commonly done using Film, Electronic Portal Imaging Device (EPID) and Computed Radiography (CR). However, the main problem is the use of Megavolt energy (MV) on LINAC aircraft can cause compton effects that can cause a decrease in image quality, both spatially (blurring) or point (noise). The application of the denoising wiener filter technique for geometric radiotherapy image verification is carried out to minimize the noise caused by the use of high energy in the LINAC aircraft.This research method is a quasi experimental that aims to improve the quality of anatomical images in the verification of geometric radiotherapy, especially on CR images and compared with EPID as a gold standard. This study uses Phantom CIRS to minimize the effects of radiation and 7 observers of Radiation Oncologists for image evaluation.Significant results of all aspects of anatomic information between before and after the wiener filter technique was performed with a p-value <0.01, and there was no difference in the anatomical information between the EPID and after the wiener filter technique with a p-value> 0.05. The use of CR with wiener filters can be an alternative in verification geometric radiotherapy and is able to offset the gold standard EPID.