Comparative Analysis of Commercial Independent Dose Calculation Systems for Gamma Knife Stereotactic Radiosurgery

Independent dose calculation is recommended for stereotactic radiosurgery (SRS) quality assurance. This study evaluates the accuracy of three commercial secondary dose calculation software programs-MUCheck, RadCalc, and ClearCalc-against the Elekta Leksell Gamma Plan (LGP) treatment planning system (TPS) for Gamma Knife SRS.

Dose calculations for 133 patients (239 intracranial targets) planned with the LGP TPS using the TMR10 algorithm were retrospectively analyzed with MUCheck, RadCalc, and ClearCalc. Point dose calculations were compared between each software and LGP. Statistical analysis included analysis of variance (ANOVA) and paired t-tests, with clinical tolerance assessed against the American Association of Physicists in Medicine (AAPM) Task Group (TG)-178 recommendations.

Mean differences were 0.34% ± 1.10% (MUCheck), 0.53% ±0.53% (RadCalc), and 0.63% ± 0.16% (ClearCalc). All showed statistically significant differences from LGP but remained within clinical tolerance. Clinical tolerance analysis showed 97.9%, 100%, and 100% of calculations within ±3% for MUCheck, RadCalc, and ClearCalc, respectively. ANOVA revealed significant differences among platforms (F = 10.46, P < 0.001), although all deviations remained clinically acceptable.

All three software platforms provide clinically acceptable independent dose verification for Gamma Knife SRS, with deviations well below AAPM TG-178 recommended tolerance levels. Selection of the appropriate secondary dose calculation platform should be based on institutional workflow integration and specific clinical requirements rather than statistical differences alone.