Mathematical analysis of gamma index on pretreatment patient-specific quality assurance with octavius 4D rotational phantom for 2d and 3d space

The radiotherapy centers having the license for 2D planar gamma index analysis can retrace the results into 3D planar analysis, which is always a better passing percentage rate, and no such implication of 3D volumetric analysis was found as the passing rate significantly shows a high degree of entropy in results. The effective use of 3D volumetric gamma metric can be appreciable if the CT overlay parameter is used in assessment and qualitatively the quantification can be predicted.