[Evaluation of Radiochromic Gel Dosimeter and Optical CT]

Three-dimensional (3D) radiation dosimeter has received growing interest with the implementation of highly conformal radiotherapy treatments. Optical Computed tomography (CT) scanners have been developed for 3D quantitative measurement of optical attenuation. Malachite green and Leuco Crystal Violet (LCV) dye radiochromic gels were recently developed as radiation dosimeters in combination with optical CT scanners. Malachite green and LCV are colorless dyes and they become green or violet after irradiation, respectively. The dyes mixed with gelatin and surfactant became hardened and can be used as a 3D gel dosimeter. The radiochromic gels dosimeter with optical CT scanners provides many of desired features such as: low cost, easy to fabricate, low toxicity and fast readout. In this article, the fundamental characteristics of radiochromic gel dosimeter with optical CT scanners are reviewed.