SU-E-T-516: Dosimetric Validation of AcurosXB Algorithm in Comparison with AAA & CCC Algorithms for VMAT Technique

Area of Science:

• Medical Physics
• Radiation Oncology
• Computational Dosimetry

Background:

• Volumetric Modulated Arc Therapy (VMAT) requires accurate dose calculation algorithms for effective cancer treatment.
• Standard algorithms like Anisotropic Analytic Algorithm (AAA) and Collapsed Cone Convolution (CCC) are widely used but have limitations.
• The AcurosXB algorithm, a grid-based Boltzmann solver, offers potential for improved accuracy and speed.

Purpose of the Study:

• To dosimetrically validate the AcurosXB dose calculation algorithm for VMAT.
• To compare AcurosXB performance against the established AAA and CCC algorithms.
• To assess the accuracy and efficiency of AcurosXB in diverse clinical scenarios.

Main Methods:

• Five clinical VMAT cases each for Brain, Head&Neck, Thoracic, and Pelvic sites, plus SBRT, were analyzed.
• Dose predictions were performed using AcurosXB, AAA, and CCC algorithms.
• Measured doses in a multicube phantom with an iMatrixx-2D detector array served as the reference for comparison.
• Gamma analysis (3mm/3% and 2mm/2% criteria) was conducted to evaluate dose agreement.

Main Results:

• AcurosXB demonstrated strong agreement with AAA and CCC, with mean correlation coefficients around 0.998.
• Mean area gamma values for AcurosXB were 98.08% (3mm/3%) and 92.36% (2mm/2%), indicating high spatial accuracy.
• Mean average gamma values for AcurosXB were 0.28 (3mm/3%) and 0.42 (2mm/2%), signifying excellent dose agreement.

Conclusions:

• The AcurosXB algorithm provides dosimetrically accurate dose predictions for VMAT across various clinical sites.
• AcurosXB shows comparable and favorable agreement with AAA and CCC algorithms.
• AcurosXB is a valid, accurate, and efficient alternative for VMAT dose calculations in busy clinical settings.