Prog Med Phys.  2012 Sep;23(3):138-144.

Preliminary Investigations of the Dosimetric Properties of a Normoxic Polymethacrylic Acid Gel Dosimeter Using a Respiration-Motion Simulator

• Park CH
• Cho YR
• Cho KH
• Park JA
• Kim KM
• Kim KB
• Jung HJ
• Ji YH
• Kwon SI

Abstract

Dose distribution throughout the clinical organ range of motion was analyzed using a respiratory-motion simulator that was equipped with a polymer gel dosimeter and EBT2 film. The normoxic polymer gel dosimeter was synthesized from gelatin, MAA, HQ, THPC and HPLC. The gel dosimeter and EBT2 film were irradiated with Co-60 gamma rays that were moved along the x-axis and y-axis in +/-1.5 cm steps at five-second intervals. The field size was 5x5 cm2. The SSD was 80 cm and set to 10 Gy at a depth of 2 cm. The PDD at a depth of 50 mm was 75.2% in the ion chamber, 82.3% in the static state and 86.1% in the dynamic state in the gel dosimeter. The penumbra for the dynamic state target, which was measured using the gel dosimeter, averaged 10.89 mm, this is a 40.5% increase over the penumbra of the static state target of 7.74 mm. In addition, when measuring with gel dosimetry, the value for the penumbra is 36.6% smaller in the static state and 29.4% smaller in the dynamic state compared to measuring with film. The aim of this study was to investigate the dosimetric properties of a normoxic polymethacrylic acid gel dosimeter in static and dynamic states and to evaluate the potentiality as a relative dosimeter for dynamic therapeutic radiation.

Keyword

Polymer gel dosimeter; Film; Moving target; Dose response

MeSH Terms

Chromatography, High Pressure Liquid
Gamma Rays
Gelatin
Organophosphorus Compounds
Polymers
Polymethacrylic Acids
Range of Motion, Articular
Silver Sulfadiazine
Gelatin
Organophosphorus Compounds
Polymers
Polymethacrylic Acids
Silver Sulfadiazine