The potential of an optical surface tracking system in non-coplanar single isocenter treatments of multiple brain metastases.

The potential of an optical surface tracking system in non-coplanar single isocenter treatments of multiple brain metastases.
J Appl Clin Med Phys. 2020 Apr 01;:
Authors: Swinnen ACC, Öllers MC, Loon Ong C, Verhaegen F
Abstract
To evaluate the accuracy of a commercial optical surface tracking (OST) system and to demonstrate how it can be implemented to monitor patient positioning during non-coplanar single isocenter stereotactic treatments of brain metastases. A 3-camera OST system was used (Catalyst HD™, C-RAD) on a TruebeamSTx with a 6DoF couch. The setup accuracy and agreement between the OST system, and CBCT and kV-MV imaging at couch angles 0° and 270°, respectively, were examined. Film measurements at 3 depths in the Rando-Alderson phantom were performed using a single isocenter non-coplanar VMAT plan containing 4 brain lesions. Setup of the phantom was performed with CBCT at couch 0° and subsequently monitored by OST at other couch angles. Setup data for 7 volunteers were collected to evaluate the accuracy and reproducibility of the OST system at couch angles 0°, 45°, 90°, 315°, and 270°. These results were also correlated to the couch rotation offsets obtained by a Winston-Lutz (WL) test. The Rando-Alderson phantom, as well as volunteers, were fixated using open face masks (Orfit). For repeated tests with the Rando-Alderson phantom, deviations between rotational and translational isocenter corrections for CBCT and ...

Source: Journal of Applied Clinical Medical Physics - March 31, 2020 Category: Physics Authors: Swinnen ACC, Öllers MC, Loon Ong C, Verhaegen F Tags: J Appl Clin Med Phys Source Type: research