Arman Sarfehnia1,2, Mark Ruschin1,2, Brige Chugh1,2, Collins Yeboah1,2, Nathan Becker1,3, Young-Bin Cho1,3, Young Lee1,2. 1. Department of Radiation Oncology, University of Toronto, 150 College St., Toronto, ON, M5S-3E2, Canada. 2. Department of Medical Physics, Odette Cancer Centre, Sunnybrook Health Sciences Centre, 2075 Bayview Ave., Toronto, ON, M4N-3M5, Canada. 3. Department of Medical Physics, Princess Margaret Cancer Centre, 610 University Ave., Toronto, ON, M5G-2M9, Canada.
Abstract
PURPOSE: This work describes the performance characterization of a cone-beam CT-guided radiosurgery device, the Gamma Knife® Icon™. METHODS: The performance tests have been categorized into: (a) image quality and mechanical integrity; (b) image coregistration fidelity; (c) adaptive treatment delivery quality; (d) high definition motion management performance characterization; (e) software communication performance testing of the integrated cone-beam CT (CBCT) system. RESULTS: All image quality performance characterization satisfied or exceeded manufacturer specifications. The image quality and mechanical stability of the CBCT system over a 3-month period was within tolerance with negligible (<0.1°) detector tilt angle. The CBCT definition of the stereotactic space had a measured average discrepancy of 0.15-0.16 mm in x, y, and z directions. On average, the high definition motion management system performance was within 0.05 mm with a residual offset of 0.15 mm when large displacements in a given direction were taken. The adaptive treatment delivery component as measured with CBCT coregistration of daily setups against reference setup images was accurate to within 0.2°. Comprehensive end-to-end testing showed a total uncertainty of better than 0.2 mm in positioning and 0.4% in dosimetry for treatment of centrally located lesions. CONCLUSIONS: A set of system performance characterization tests spanning all aspects of the Gamma Knife Icon are presented. Overall, the system performance was in line with manufacturer specifications.
PURPOSE: This work describes the performance characterization of a cone-beam CT-guided radiosurgery device, the Gamma Knife® Icon™. METHODS: The performance tests have been categorized into: (a) image quality and mechanical integrity; (b) image coregistration fidelity; (c) adaptive treatment delivery quality; (d) high definition motion management performance characterization; (e) software communication performance testing of the integrated cone-beam CT (CBCT) system. RESULTS: All image quality performance characterization satisfied or exceeded manufacturer specifications. The image quality and mechanical stability of the CBCT system over a 3-month period was within tolerance with negligible (<0.1°) detector tilt angle. The CBCT definition of the stereotactic space had a measured average discrepancy of 0.15-0.16 mm in x, y, and z directions. On average, the high definition motion management system performance was within 0.05 mm with a residual offset of 0.15 mm when large displacements in a given direction were taken. The adaptive treatment delivery component as measured with CBCT coregistration of daily setups against reference setup images was accurate to within 0.2°. Comprehensive end-to-end testing showed a total uncertainty of better than 0.2 mm in positioning and 0.4% in dosimetry for treatment of centrally located lesions. CONCLUSIONS: A set of system performance characterization tests spanning all aspects of the Gamma Knife Icon are presented. Overall, the system performance was in line with manufacturer specifications.
Authors: Nels C Knutson; Brad J Hawkins; Douglas Bollinger; S Murty Goddu; James A Kavanaugh; Lakshmi Santanam; Timothy J Mitchell; Jacqueline E Zoberi; Christina Tsien; Jiayi Huang; Clifford G Robinson; Stephanie M Perkins; Joshua L Dowling; Michael R Chicoine; Keith M Rich; Gavin P Dunn; Sasa Mutic Journal: J Appl Clin Med Phys Date: 2019-05-04 Impact factor: 2.102