Frameless Gamma Knife Radiosurgery with Leksell ICON: Initial Experience

Area of Science:

• Neurosurgery
• Radiation Oncology
• Medical Physics

Background:

• Lars Leksell pioneered stereotactic radiosurgery, leading to the development of the Leksell Gamma Knife (LGK).
• The LGK Perfexion model has been widely used, with the sixth-generation LGK ICON now introducing advanced features.
• The ICON model integrates Cone-Beam Computed Tomography (CBCT) for enhanced treatment delivery.

Purpose of the Study:

• To evaluate the feasibility and characteristics of frameless gamma knife surgery using the LGK ICON.
• To assess the accuracy and patient experience with the non-invasive thermoplastic mask fixation system.
• To explore the potential of the ICON's CBCT module and intra-fraction motion management.

Main Methods:

• Utilized the Leksell Gamma Knife ICON system with its Cone-Beam Computed Tomography (CBCT) module.
• Employed frameless treatment protocols with non-invasive thermoplastic mask fixation.
• Monitored patient positioning, dosimetry, radiation delivery times, and intra-fraction motion.

Main Results:

• Successfully conducted frameless gamma knife surgeries in approximately 25% of planned cases.
• Observed specific characteristics of the thermoplastic mask system: simple dosimetry, short delivery times, and cooperative patients.
• Identified challenges related to intra-fraction errors despite the system's sub-millimeter accuracy capabilities.

Conclusions:

• The LGK ICON facilitates frameless stereotactic radiosurgery with promising results, despite challenges with intra-fraction motion.
• The non-invasive approach offers advantages in patient comfort and treatment efficiency.
• Further adoption of this advanced automation is anticipated for broader patient application.