FIGURE 1.

Measured and TPS‐calculated PDDs for the (a) 10 × 1 cm² and (b) 10 × 2 cm² field sizes. Measured and calculated crossline (orthogonal to direction of couch motion) profiles for (c) 10×1 cm² and (d) 10 × 2 cm² fields. Measured and calculated inline (parallel to direction of couch motion) profiles for (e) 10 × 1 cm² and (f) 10 × 2 cm² fields. All measurements and calculations were performed in a homogeneous water phantom at an SSD of 85 cm. Measurements were performed with the Sun Nuclear Edge diode in the IBA Blue Phantom Helix water tank. Gamma criteria of 1%/1 mm were used to compute the Gamma index