Dosimetric comparison between cone/Iris-based and InCise MLC-based CyberKnife plans for single and multiple brain metastases.

Dosimetric comparison between cone/Iris-based and InCise MLC-based CyberKnife plans for single and multiple brain metastases. J Appl Clin Med Phys. 2016;17(5):6260 Authors: Jang SY, Lalonde R, Ozhasoglu C, Burton S, Heron D, Huq MS Abstract We performed an evaluation of the CyberKnife InCise MLC by comparing plan qualities for single and multiple brain lesions generated using the first version of InCise MLC, fixed cone, and Iris collimators. We also investigated differences in delivery efficiency among the three collimators. Twenty-four patients with single or multiple brain mets treated previously in our clinic on a CyberKnife M6 using cone/Iris collimators were selected for this study. Treatment plans were generated for all lesions using the InCise MLC. Number of monitor units, delivery time, target coverage, conformity index, and dose falloff were compared between MLC- and clinical cone/Iris-based plans. Statistical analysis was performed using the non-parametric Wilcoxon-Mann-Whitney signed-rank test. The planning accuracy of the MLC-based plans was validated using chamber and film measurements. The InCise MLC-based plans achieved mean dose and target coverage comparable to the cone/Iris-based plans. Although the conformity indices of the MLC-based plans were slightly higher than those of the cone/Iris-based plans, beam delivery time for the MLC-based plans was shorter by 30% ~ 40%. For smaller targets or cases with OARs located ...
Source: Journal of Applied Clinical Medical Physics - Category: Physics Authors: Tags: J Appl Clin Med Phys Source Type: research