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Initial experience with an electron FLASH research extension (FLEX) for the Clinac system
Kyuhak Oh1, Kyle J Gallagher1, Megan Hyun1
1University of Nebraska Medical Center, Omaha, Nebraska, USA.
Journal of Applied Clinical Medical Physics
|September 22, 2023
Summary
Researchers commissioned a new electron FLASH radiotherapy system for preclinical studies. This system enables ultra-high-dose-rate research, showing reduced impact on normal cells compared to conventional rates.
Area of Science:
- Medical Physics
- Radiation Oncology
- Preclinical Research
Background:
- Ultra-high-dose-rate radiotherapy, known as FLASH, offers potential to improve cancer treatment by widening the therapeutic window.
- The mechanisms of the FLASH effect are not fully understood, and access to specialized equipment is limited.
Purpose of the Study:
- To conduct acceptance and commissioning tests for a novel electron FLASH research system designed for preclinical applications.
- To characterize the dosimetric properties and performance of the new system.
Main Methods:
- A modified linear accelerator (Clinac 23EX) with a FLASH extension (Clinac-FLEX) was used to deliver a 16 MeV electron beam.
- Radiochromic film, optically stimulated luminescent dosimeters, and ionization chambers were employed for characterization.
- Radiation shielding of the existing vault was assessed.
Main Results:
- The Clinac-FLEX system achieved FLASH dose rates exceeding 3.8 Gy/pulse.
- Depth dose curves and beam profiles were analyzed, showing good agreement with conventional modes for smaller field sizes.
- Preliminary studies indicated significantly less impact on normal cell morphology at FLASH dose rates (180 Gy/s) versus conventional rates (18 Gy/s).
Conclusions:
- The Clinac-FLEX system is a viable platform for preclinical FLASH radiotherapy research.
- This system can increase accessibility to ultra-high-dose-rate research capabilities for the scientific community.
Keywords:
FLASH Research Extension (FLEX)cell viabilityconventional dose rate (CONV)dosimetryelectron Ultra-high dose rate (eFLASH)linear acceleratorstress-activated senescenceMore Related Videos
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