An intracavitary cone system for electron beam therapy using a Therac 20 linear accelerator

Area of Science:

• Medical Physics
• Radiation Oncology

Background:

• The Therac 20 linear accelerator produces electron and photon beams.
• Standard collimators are unsuitable for intracavitary treatment.
• A need exists for specialized electron beam delivery in confined spaces.

Purpose of the Study:

• To design and evaluate an intracavitary cone system for the Therac 20.
• To enable safe and effective intracavitary electron beam therapy.
• To report dosimetry data for the new system.

Main Methods:

• Designed an intracavitary cone system attaching to existing electron trimmers.
• The system includes a platform with a lead insert.
• Dosimetry measurements were performed for 9, 13, and 17 MeV electron beams with three different cones.

Main Results:

• The intracavitary cone system attaches to the Therac 20 without removing trimmers.
• The system does not require bypassing the interlock system.
• Dosimetry data for various electron energies and cone sizes were obtained.

Conclusions:

• The designed intracavitary cone system is a viable solution for Therac 20 intracavitary treatments.
• This system allows for precise electron beam collimation in clinical settings.
• The dosimetry measurements provide essential data for treatment planning.