Experimental and Monte Carlo based dosimetric investigation of a novel 3 mm radiosurgery 3 MV beam using the microSilicon detector.
Monte Carlo simulations
microSilicon detector
radiosurgery
small field dosimetry
volume effect
Journal
Journal of applied clinical medical physics
ISSN: 1526-9914
Titre abrégé: J Appl Clin Med Phys
Pays: United States
ID NLM: 101089176
Informations de publication
Date de publication:
19 May 2024
19 May 2024
Historique:
revised:
15
03
2024
received:
05
10
2023
accepted:
15
04
2024
medline:
19
5
2024
pubmed:
19
5
2024
entrez:
19
5
2024
Statut:
aheadofprint
Résumé
The ZAP-X system is a novel gyroscopic radiosurgical system based on a 3 MV linear accelerator and collimator cones with a diameter between 4 and 25 mm. Advances in imaging modalities to detect small and early-stage pathologies allow for an early and less invasive treatment, where a smaller collimator matching the anatomical target could provide better sparing of surrounding healthy tissue. A novel 3 mm collimator cone for the ZAP-X was developed. This study aims to investigate the usability of a commercial diode detector (microSilicon) for the dosimetric characterization of this small collimator cone; and to investigate the underlying small field perturbation effects. Profile measurements in five depths as well as PDD and output ratio measurements were performed with a microSilicon detector and radiochromic EBT3 films. In addition, comprehensive Monte Carlo simulations were performed to validate the measurement observations and to quantify the perturbation effects of the microSilicon detector in these extremely small field conditions. It is shown that the microSilicon detector enables an accurate dosimetric characterization of the 3 mm beam. The profile parameters, such as the FWHM and 20%-80% penumbra width, agree within 0.1 to 0.2 mm between film and detector measurements. The output ratios agree within the measurement uncertainty between microSilicon detector and films, whereas the comparisons of the PDD results show good agreement with the Monte Carlo simulations. The analysis of the perturbation factors of the microSilicon detector reveals a small field correction factor of approximately 3% for the 3 mm circular beam and a correction factor smaller than 1.5% for field diameters above 3 mm. It could be shown that the microSilicon detector is well-suitable for the characterization of the new 3 mm circular beam of the ZAP-X system.
Sections du résumé
BACKGROUND
BACKGROUND
The ZAP-X system is a novel gyroscopic radiosurgical system based on a 3 MV linear accelerator and collimator cones with a diameter between 4 and 25 mm. Advances in imaging modalities to detect small and early-stage pathologies allow for an early and less invasive treatment, where a smaller collimator matching the anatomical target could provide better sparing of surrounding healthy tissue.
PURPOSE
OBJECTIVE
A novel 3 mm collimator cone for the ZAP-X was developed. This study aims to investigate the usability of a commercial diode detector (microSilicon) for the dosimetric characterization of this small collimator cone; and to investigate the underlying small field perturbation effects.
METHODS
METHODS
Profile measurements in five depths as well as PDD and output ratio measurements were performed with a microSilicon detector and radiochromic EBT3 films. In addition, comprehensive Monte Carlo simulations were performed to validate the measurement observations and to quantify the perturbation effects of the microSilicon detector in these extremely small field conditions.
RESULTS
RESULTS
It is shown that the microSilicon detector enables an accurate dosimetric characterization of the 3 mm beam. The profile parameters, such as the FWHM and 20%-80% penumbra width, agree within 0.1 to 0.2 mm between film and detector measurements. The output ratios agree within the measurement uncertainty between microSilicon detector and films, whereas the comparisons of the PDD results show good agreement with the Monte Carlo simulations. The analysis of the perturbation factors of the microSilicon detector reveals a small field correction factor of approximately 3% for the 3 mm circular beam and a correction factor smaller than 1.5% for field diameters above 3 mm.
CONCLUSIONS
CONCLUSIONS
It could be shown that the microSilicon detector is well-suitable for the characterization of the new 3 mm circular beam of the ZAP-X system.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
e14388Informations de copyright
© 2024 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, LLC on behalf of The American Association of Physicists in Medicine.
Références
Friehs GM, Park MC, Goldman MA, Zerris VA, Norén G, Sampath P. Stereotactic radiosurgery for functional disorders. Neurosurgical Focus. 2007;23(6):E2.
Kondziolka D, Perez B, Flickinger JC, Habeck M, Lunsford LD. Gamma knife radiosurgery for trigeminal neuralgia: results and expectations. Arch Neurol. 1998;55(12):1524‐1529.
Erbay SH, Bhadelia RA, O'Callaghan M, et al. Nerve atrophy in severe trigeminal neuralgia: noninvasive confirmation at MR imaging—initial experience. Radiology. 2006;238(2):689‐692.
Su JH, Thomas FT, Kasoff WS, et al. Thalamus Optimized Multi Atlas Segmentation (THOMAS): fast, fully automated segmentation of thalamic nuclei from structural MRI. Neuroimage. 2019;194:272‐282.
Schneider MB, Walcott B, Adler Jr JR. Neuromodulation via focal radiation: radiomodulation update. Cureus. 2021;13(4):e14700.
Wang X, Chang C, Adler Jr JR, et al. A randomized blinded trial of nucleus accumbens ablation to treat opiate dependence in humans: location correlates with outcome. Cureus. 2012;4(6):e49.
De Salles AA, Melega WP, Laćan G, Steele LJ, Solberg TD. Radiosurgery performed with the aid of a 3‐mm collimator in the subthalamic nucleus and substantia nigra of the vervet monkey. J Neurosurg. 2001;95(6):990‐997.
Weidlich GA, Schneider MB, Adler Jr JR. Self‐shielding analysis of the Zap‐X system. Cureus. 2017;9(12):e1917.
Weidlich GA, Schneider MB, Adler Jr JR. Characterization of a novel revolving radiation collimator. Cureus. 2018;10(2):e2146.
Delbaere A, Younes T, Simon L, Khamphan C, Vieillevigne L. Field output correction factors and electron fluence perturbation of the microSilicon and microSilicon X detectors. Phys Med Biol. 2022;67(8):08NT01.
Francescon P, Kilby W, Noll J, Satariano N, Orlandi C. Small field dosimetry correction factors for circular and MLC shaped fields with the CyberKnife M6 System: evaluation of the PTW 60023 microSilicon detector. Phys Med Biol. 2020;65(1):01NT01.
McGrath AN, Golmakani S, Williams TJ. Determination of correction factors in small MLC‐defined fields for the Razor and microSilicon diode detectors and evaluation of the suitability of the IAEA TRS‐483 protocol for multiple detectors. J Appl Clin Medical Phys. 2022;23(7):e13657.
Schönfeld AB, Poppinga D, Kranzer R, et al. Characterization of the new microSilicon diode detector. Med Phys. 2019;46(9):4257‐4262.
Weber C, Kranzer R, Weidner J, et al. Small field output correction factors of the microSilicon detector and a deeper understanding of their origin by quantifying perturbation factors. Med Phys. 2020;47(7):3165‐3173.
Poppinga D, Delfs B, Meyners J, Harder D, Poppe B, Looe HK. The output factor correction as function of the photon beam field size–direct measurement and calculation from the lateral dose response functions of gas‐filled and solid detectors. Zeitschrift für Medizinische Physik. 2018;28(3):224‐235.
Poppinga D, Schoenfeld AA, Doerner K‐J, Blanck O, Harder D, Poppe B. A new correction method serving to eliminate the parabola effect of flatbed scanners used in radiochromic film dosimetry. Med Phys. 2014;41(2):021707.
Schoenfeld AA, Poppinga D, Harder D, Doerner K‐J, Poppe B. The artefacts of radiochromic film dosimetry with flatbed scanners and their causation by light scattering from radiation‐induced polymers. Phys Med Biol. 2014;59(13):3575.
Massillon‐JL G, Chiu‐Tsao S‐T, Domingo‐Munoz I, Chan MF. Energy dependence of the new Gafchromic EBT3 film: dose response curves for 50 kV, 6 and 15 MV X‐ray beams. Int J Med Phys Clin Eng Radiat Oncol. 2012;1(2):60‐65.
Looe HK, Harder D, Poppe B. Understanding the lateral dose response functions of high‐resolution photon detectors by reverse Monte Carlo and deconvolution analysis. Phys Med Biol. 2015;60(16):6585.
Delfs B, Blum I, Tekin T, et al. The role of the construction and sensitive volume of compact ionization chambers on the magnetic field‐dependent dose response. Med Phys. 2021;48(8):4572‐4585.
Blum I, Tekin T, Delfs B, et al. The dose response of PTW microDiamond and microSilicon in transverse magnetic field under small field conditions. Phys Med Biol. 2021;66(15):155003.
Pinnaduwage DS, Srivastava SP, Yan X, et al. Small‐field beam data acquisition, detector dependency, and film‐based validation for a novel self‐shielded stereotactic radiosurgery system. Med Phys. 2021;48(10):6121‐6136.
Akino Y, Fujiwara M, Okamura K, et al. Characterization of a microSilicon diode detector for small‐field photon beam dosimetry. J Radiat Res (Tokyo). 2020;61(3):410‐418.
Palmans H, Andreo P, Huq MS, Seuntjens J, Christaki KE, Meghzifene A. Dosimetry of smalll static fields used in external photon beam radiotherapy: summary of TRS‐483, the IAEA‐AAPM international Code of Practice for reference and relative dose determination. Med Phys. 2017;45(11):e1123‐e1145.