Improper positioning leads to patient forearm in beam. Occurred in 7 of 10 treatment fractions..²

Deviation in left arm position causes exposure in armpit area. Seen in 1 of 15 fractions.²

Partial coverage of treatment area with bolus in 7 of 14 treatments imaged.²

Difficult to set-up patient (arm down) leads to unintended dose to contralateral breast.³

Treatment plan included an unintentional open MLC leaf.³

Chin exposure seen during delivery. Corrected mid-treatment by the treating therapist.²