Dosimetric characterization of CyberKnife? robotic SRS using MOSFET-based "MOskin" detector

Aim: This study assesses the implementation of MOSkin detectors for the SRS dosimetry of the CyberKnife & REG; system.Method: The performance of the MOSkin detectors was evaluated by using Iris collimators on water-equivalent phantoms in the CyberKnife & REG; system. The dosimetric evaluation included measurements of the tissue-phantom ratio (TPR), output factor, and off-axis ratio. The results of the MOSkin sensors were compared with those of PTW 60016 and EDGE diodes.Results: The TPR measurements obtained by the MOSkin devices exhibited conformity lower than 2.9% compared with the results of the PTW60016 diodes across the field sizes considered. The output factor was consistent to within 2.8% of that of the EDGE detectors, following adjustment based on the appropriate field correction factors. The off-axis ratio of the MOSkin detectors corresponded to that of the EDGE diodes, with an FWHM of 4.3% and a penumbra narrower than 0.22 mm.Conclusion: MOSkin sensors are strong contenders for Cyberknife & REG; quality assurance of both machines and patients, as they are capable of reproducing measurements obtained by commercial sensors with an acceptable degree of precision.