Whole Three-Dimensional Dosimetry of Carbon Ion Beams with an MRI-Based Nanocomposite Fricke Gel Dosimeter Using Rapid T1 Mapping Method

Abstract

MRI-based gel dosimeters are attractive systems for the evaluation of complex dose distributions in radiotherapy. In particular, the nanocomposite Fricke gel dosimeter is one among a few dosimeters capable of accurately evaluating the dose distribution of heavy ion beams. In contrast, reduction of the scanning time is a challenging issue for the acquisition of three-dimensional volume data. In this study, we investigated a three-dimensional dose distribution measurement method for heavy ion beams using variable flip angle (VFA), which is expected to significantly reduce the MRI scanning time. Our findings clarified that the whole three-dimensional dose distribution could be evaluated within the conventional imaging time (20 min) and quality of one cross-section.

Gel Dosimetry

“…In the study of Mizukami et al [ 16 ], the authors investigated the whole 3D dosimetry of carbon ion beam gel dosimetry by applying a new rapid MR imaging method. The rapid and accurate measurement of the T 1 relaxation time also remains an important goal in clinical examinations.…”

Preliminary research on the dose response of polymer gel dosimeter with carbon beam irradiation

“…Maeyama et al [2] studied the radiological characteristics of VIP polymer gel under carbon beam irradiation. Mizukami et al [3] studied a nanocomposite Fricke gel dosimeter under carbon ion beams irradiation. Furuta et al [4] compared Monto Carlo simulation and measurement with PAGAT gel in biological samples for carbon ion beam.…”

Study of the Optimal Composition and Storage Conditions of the Fricke–XO–Pluronic F–127 Radiochromic Dosimeter

“…Numerous studies focused on different aspects regarding Fricke 3D dosimetry, including optimization of gel dosimeter’s formulae, stability, reproducibility, and dose response characterizations by using different radiation sources and reducing the diffusion of Fe +3 ions after irradiation [ 9 , 10 , 11 , 12 ].…”