Analyzation of Clinical Proton Therapy Beams

Mentor 1

Sarah Patch

Location

Union Wisconsin Room

Start Date

28-4-2017 1:30 PM

End Date

28-4-2017 4:00 PM

Description

Particle therapy deposits less radiation in healthy tissue than conventional radiation because doctors are able to control where the majority of the beam's energy is delivered. Thus, larger doses of radiation can be prescribed. Clinical particle therapy beams can administer ions in various doses and propagate protons to two-thirds the speed of light. The range and straggle of these beams is easily affected by internal structures, so it is imperative they hit their target to avoid unnecessary damage to vital bodily tissues. Experiments requiring use of clinical beams are expensive and difficult to schedule. Therefore, we model and analyze them using SRIM Monte-Carlo software. After we obtained the specifications of various particle therapy beams (Varian, Mevion, and IBA), we ran multiple simulations of 90k hydrogen ions into water and other tissue mimicking materials with known stopping power. For instance, the Varian system accelerates protons to 230MeV with an energy spread of 99.5keV and a Gaussian lateral profile with 3.6mm standard deviation upon entry into the water target. Longitudinal range is 32.56cm and lateral range is 5.23mm. Accelerating these same protons into targets with a tissue mimicking layer yields comparable results with a longitudinal range of 32.45cm and lateral range of 5.14mm. A similar longitudinal range is obtained when a 5.2mm bone layer is inserted between two tissue mimicking layers. Other vendors offer similar beams; all induce thermoacoustic pressure of about 1 Pa/pC (roughly 1 cGy/pC) delivered to the target.

This document is currently not available here.

Share

COinS
 
Apr 28th, 1:30 PM Apr 28th, 4:00 PM

Analyzation of Clinical Proton Therapy Beams

Union Wisconsin Room

Particle therapy deposits less radiation in healthy tissue than conventional radiation because doctors are able to control where the majority of the beam's energy is delivered. Thus, larger doses of radiation can be prescribed. Clinical particle therapy beams can administer ions in various doses and propagate protons to two-thirds the speed of light. The range and straggle of these beams is easily affected by internal structures, so it is imperative they hit their target to avoid unnecessary damage to vital bodily tissues. Experiments requiring use of clinical beams are expensive and difficult to schedule. Therefore, we model and analyze them using SRIM Monte-Carlo software. After we obtained the specifications of various particle therapy beams (Varian, Mevion, and IBA), we ran multiple simulations of 90k hydrogen ions into water and other tissue mimicking materials with known stopping power. For instance, the Varian system accelerates protons to 230MeV with an energy spread of 99.5keV and a Gaussian lateral profile with 3.6mm standard deviation upon entry into the water target. Longitudinal range is 32.56cm and lateral range is 5.23mm. Accelerating these same protons into targets with a tissue mimicking layer yields comparable results with a longitudinal range of 32.45cm and lateral range of 5.14mm. A similar longitudinal range is obtained when a 5.2mm bone layer is inserted between two tissue mimicking layers. Other vendors offer similar beams; all induce thermoacoustic pressure of about 1 Pa/pC (roughly 1 cGy/pC) delivered to the target.