Linearity and image uniformity of the Vista~(TM) optical cone beam scanner

摘要

This report is an initial evaluation of the Vista~(TM) optical cone beam scanner (Modus Medical Devices, London Canada). Results from this first research model will assist is identifying improvements required to make a system for accurate clinical 3D gel dosimetry. The initial test involves scanning coloured transparent solutions and comparing optical CT attenuation coefficients with independent measurements of the solutions obtained with an absorption spectrometer. For such transparent solutions, optical attenuation is due primarily to absorption. Quantitative agreement must be established with these low scatter systems prior to evaluating densitometric and dosimetric performance with highly scattering gel materials.