Open-face immobilisation masks for brain and head and neck radiotherapy where surface guidance can check the position

What changes. A closed thermoplastic mask covers the face and is fixed to the couch. An open-face mask leaves the eyes, nose and mouth uncovered; because the radiographers can no longer use the mask alone to confirm the position, a surface camera watches the exposed face during treatment.

The randomised evidence. In a single-centre self-controlled trial, 30 people having fractionated brain radiotherapy had both masks made and switched halfway through treatment. Mean discomfort on a 10-point scale was 0.5 with the open mask against 3.3 with the closed one (p below 0.0001), anxiety and pain were also lower, 27 of 29 preferred the open mask, and movement during treatment did not differ. In a randomised trial of 106 people with head and neck cancer, open-face masks with foam support gave set-up errors no different from closed masks in most directions, with the trial also measuring comfort, anxiety and depression. A 2024 scoping review of 19 studies, most published since 2020, found sub-millimetre reproducibility with open masks and surface guidance.

Limits. Most evidence is in brain treatment, where the target moves little; head and neck radiotherapy, where the neck and jaw move and the mask often extends to the shoulders, has less. Open masks depend on surface guidance being available. Adoption is not measured.