Investigation of Verification Methods of Field Matching Using Polymer Gel Dosimeter in Proton Therapy

Purpose In our proton beam therapy center, we use imaging plates (IP) for dose verification of field matching in irradiation (called patch-field technique). this study, a polymer gel dosimeter, which can perform three- dimensional distribution measurement, was used as new tool the patch method corresponding to rectangular irradiation. Method The results measurements PAGAT dosimeter irradiate two fields called fields, were created using treatment planning system, evaluated and compared IP plan profiles near boundary fields. Result case no gap between relative 10.1% higher that measured with midpoint overlap hot region), result gels 6.3% than IP. space cold 14.9% difference 14.2% (no gap), -5.0% (hot), 10.5% (cold). Conclusion We found 3-D dosimetric possibility preliminary included several error factors. future, it is necessary develop improved more precise measurements.