Fig. 2
From: Impact of beam configuration on VMAT plan quality for Pinnacle3Auto-Planning for head and neck cases
Comparison of plan quality with the COV method. Plan quality was evaluated and COV ratios for comparison #1–3 are shown. Plan quality of V2C15 is superior if the first COV ratio is below 1 (open circles) and the second COV ratio is greater than 1 (filled circles). a COV ratios for comparison #1: single arc (V1C15) and double arc (V2C15) for 20 patients. b COV ratios for two single arcs with collimator rotation (2V1C15) and double arc (V2C15) for 20 patients. c COV ratios for full (V2C15) and partial arcs (V2C15_Part) for 10 patients with unilateral target volumes