Table 1.

Mechanical and dosimetric tests done during commissioning and when the machine undergoes major maintenance

1. Mechanical Checks

1.1 Stability of the dMLC

1.2 Stability of leaf speed

1.3 Sensitivity to treatment interruptions (acceleration and deceleration)

1.4 Evaluation of standard patterns, Varian test (13)

• synchronized segmented stripes

• nonsynchronized segmented stripes

• x wedges

• Y wedges

• pyramids

• complex field A

• complex field B

1.5 Evaluation of fields with multiple carriage position

2. Dosimetric Checks

2.1 Stability of dMLC output sweeping gap test (central axis (CAX) vs. gantry and collimator angles)

2.2 Segmental dose accuracy check

2.3 Determination of average leaf transmission

2.4 Determination of dosimetric leaf separation

2.5 Effects of lateral disequilibrium in dose profile between adjacent leaves