Irradiation of small structures through the intact skull

Area of Science:

• Medical Physics
• Radiation Oncology
• Neurosurgery

Background:

• Developing precise radiation delivery techniques is crucial for functional radiation surgery.
• Routine clinical application requires high physical and mechanical reproducibility in treatment procedures.

Purpose of the Study:

• To discuss the physical conditions for producing minute, disc-shaped lesions using narrow beam irradiation.
• To investigate various radiation types for their suitability in routine clinical functional radiation surgery.
• To identify the optimal radiation source and design a specialized treatment apparatus.

Main Methods:

• Investigated the use of high energy electrons, supervoltage roentgen radiation, gamma emitting nuclides, and fast neutrons.
• Evaluated radiation types based on physical properties, radiobiological factors, and practical clinical considerations.
• Designed and constructed a treatment apparatus utilizing 179 Cobalt-60 sources.

Main Results:

• Cobalt-60 gamma radiation was identified as the radiation of choice.
• The chosen radiation offers a favorable balance of physical, biological, and practical attributes.
• A specialized apparatus was successfully constructed for delivering targeted radiation.

Conclusions:

• Cobalt-60 gamma radiation is suitable for producing precise lesions in functional radiation surgery.
• The developed treatment apparatus facilitates reproducible and clinically applicable radiation procedures.
• This approach supports the routine clinical use of narrow beam irradiation for targeted treatments.