The radiation therapist’s role in real-time EPI interpretation and decision-making

Purpose

To determine whether radiation therapists (RTT) can correctly identify field placement errors and recommend appropriate isocentre moves using electronic portal imaging.

Methods

A systematic review of the literature was made using the keywords: “radiation therapy OR radiotherapy AND electronic portal imaging”; radiation therapist OR radiographer OR radiologic technologist AND electronic portal imaging”; “electronic portal imaging”; “verification AND electronic portal imaging”; “verification AND radiation therapist”; “verification films”; “image approval”; “radiation therapist AND role expansion”; and “radiation therapist experience”.

Results

Eighteen relevant articles were found. These were collated into three topic areas: 1) current practice, 2) ability to assess EPIs, and 3) experience/education needed. It is common practice for RTTs to review EPIs in Canada, Australia and New Zealand. Education is carried out in the clinic. Concordance between RTTs and radiation oncologists (ROs) in error detection and iso-move decisions was between 90.1% and 97.3%. RTT inter-observer variability was 0.7–1.4 mm and intra-observer variability was 0.4–0.7 mm.

Conclusions

RTTs provide acceptable alternatives to ROs for rapid review of EPIs, enabling prompt corrections to be made with the patient on the treatment couch. It is recommended that RTTs take on this role, using an internal accrediting program and ongoing continual professional education.