Evaluation of stability of stereotactic space defined by cone-beam CT for the Leksell Gamma Knife Icon.

In this study, we used an in-house built marker tool to evaluate the stability of the CBCT-based stereotactic space and its agreement with the standard frame-based stereotactic space. We imaged the tool with a CT indicator box using our CT-simulator at the beginning, middle, and end of the study period (6 weeks) for determining the frame-based stereotactic space. The tool was also scanned with the Icon's CBCT on a daily basis throughout the study period, and the CBCT images were used for determining the CBCT-based stereotactic space. The coordinates of each marker were determined in each CT and CBCT scan using the Leksell GammaPlan treatment planning software. The magnitudes of vector difference between the means of each marker in frame-based and CBCT-based stereotactic space ranged from 0.21 to 0.33 mm, indicating good agreement of CBCT-based and frame-based stereotactic space definition. Scanning 4-month later showed good prolonged stability of the CBCT-based stereotactic space definition.
PMID: 28419781 [PubMed - as supplied by publisher]

Source: Journal of Applied Clinical Medical Physics - April 17, 2017 Category: Physics Authors: AlDahlawi I, Prasad D, Podgorsak MB Tags: J Appl Clin Med Phys Source Type: research