Gammaknife Versus Vmat Radiosurgery Plan Quality For Many Brain Metastases

Keywords

brain radiosurgery; GammaKnife; metastases; VMAT

Abstract

The purpose of this work was to compare dose distributions between two radiosurgery modalities, single-isocenter volumetric modulated arc therapy (VMAT), and GammaKnife Perfexion (GK), in the treatment of a large number (≥7) of brain metastases. Twelve patients with 103 brain metastases were analyzed. The median number of targets per patient was 8 (range: 7–14). GK plans were compared to noncoplanar VMAT plans using both 6-MV flattening filter-free (FFF) and 10-MV FFF modes. Parameters analyzed included radiation therapy oncology group conformity index (CI), 12, 6, and 3 Gy isodose volumes (V12 Gy, V6 Gy, V3 Gy), mean and maximum hippocampal dose, and maximum skin dose. There were statistically significant differences in CI (2.5 ± 1.6 vs 1.6 ± 0.8 and 1.7 ± 0.9, P < 0.001, P < 0.001), V12 Gy (2.8 ± 6.1 cc vs 3.0 ± 5.2 cc and 3.1 ± 5.4 cc, P = 0.003, P < 0.001), and V3 Gy (323.0 ± 294.8 cc vs, 880.1 ± 369.1 cc and 937.9 ± vs 361.9 cc, P = 0.005, P = 0.001) between GK versus both 6-MV FFF and 10-MV FFF. No significant differences existed for maximum hippocampal or skin doses. In conclusion, highly optimized VMAT produced improved conformity at the expense of a higher V12 Gy and V3 Gy volume when compared with highly optimized GK.

Publication Date

11-1-2018

Publication Title

Journal of Applied Clinical Medical Physics

Volume

19

Issue

6

Number of Pages

159-165

Document Type

Article

Personal Identifier

scopus

DOI Link

https://doi.org/10.1002/acm2.12471

Socpus ID

85054551607 (Scopus)

Source API URL

https://api.elsevier.com/content/abstract/scopus_id/85054551607

This document is currently not available here.

Share

COinS