End-To-End Procedure For IORT in Brain Metastases and Film Dosimetry

Area of Science:

• Medical Physics
• Radiation Oncology

Background:

• Intraoperative radiotherapy (IORT) offers precise radiation delivery during surgery.
• Quality assurance is crucial for ensuring the safety and efficacy of IORT treatments.

Purpose of the Study:

• To conduct an end-to-end test of the clinical brain IORT process using cadaver heads.
• To evaluate the dosimetric and geometric accuracy of the simulated tumor removal and irradiation procedure.

Main Methods:

• Low-energy X-ray intraoperative radiotherapy (IORT) was employed for irradiation.
• Absorbed doses were measured using radiochromic films and calculated via treatment planning system after computed tomography.
• Simulated tumor removal and irradiation were performed on cadaver heads.

Main Results:

• Maximum absorbed doses in organs at risk (OAR) were within tolerance limits.
• Verified absorbed doses in the target showed deviations of less than 1% compared to planned doses.

Conclusions:

• The tested procedure serves as a reproducible quality assurance tool for clinical brain IORT.
• Continuous assessment of dosimetric and geometric accuracy is achievable with this method.
• Measured absorbed doses in both target and OAR are optimal for brain IORT treatments.