Simulated gamma knife head frame placement for radiosurgical pre-planning

Area of Science:

• Neurosurgery
• Medical Physics
• Radiosurgery

Background:

• Leksell Gamma Knife (GK) offers precise intracranial lesion targeting.
• Headframe placement is crucial for stereotactic accuracy but can limit treatable volumes due to collisions or mechanical constraints.
• Limitations are often discovered only after initial headframe placement, potentially requiring repeat procedures.

Purpose of the Study:

• To develop and validate a software package for simulated headframe placement and collision checks.
• To minimize the need for multiple headframe placements in Leksell Gamma Knife radiosurgery.
• To assess if optimized headframe positioning can enable single-placement treatment for previously untreatable targets.

Main Methods:

• Development of a software package for pre-treatment simulation of headframe placement and collision detection.
• Validation using an anthropomorphic head phantom to assess prediction accuracy.
• Retrospective review of 25 patient cases with previously untreatable targets using the software.

Main Results:

• The software successfully predicted clinically usable headframe positions in phantom studies.
• In retrospective patient cases, the software identified that 4 out of 25 could have been treated with a single optimized headframe placement.
• The software determined that 24 out of 25 cases could not be treated with any single headframe placement.

Conclusions:

• Simulated headframe placement software can aid in planning Leksell Gamma Knife radiosurgery.
• The tool shows potential for optimizing headframe placement to avoid collisions and mechanical limits.
• While beneficial, the software cannot overcome all limitations preventing single-placement treatment for complex intracranial targets.