Same-day mask-based gamma-knife stereotactic radiosurgery: workflow analysis and impact.

Objective: Over the last 30 years, there has been a steady move towards the use of mask immobilization in SRS. Benefits of masks include the ability to hypofractionate SRS and improved patient comfort. However, there has been criticism that it eliminates the possibility of same-day, "wheels in to wheels out" treatments, as mask fixation is traditionally done on a separate day. This study evaluates the feasibility of doing mask fabrication and SRS treatment on the same day.

Methods: Patients who underwent SRS from September 2020 to June 2021 were reviewed. Leksell Gamma Knife (LGK) console data were processed, and operator reports were analyzed for treatment time, number of pauses, alarms, and pause durations.

Results: A total of 100 patients met the inclusion criteria. 52 patients underwent same-day fabrication and treatment, and 48 patients were treated at least one day following mask fabrication. Same-day patients had more frequent pauses and longer average pause durations than different-day patients. However, there were no significant differences in predicted vs. actual treatment times or the number of treatment alarms between groups.

Conclusion: Mask-based SRS can be done safely and efficiently in a single day, mirroring the approach of frame-based treatments. There is an increased number of pauses in the same-day group; however, it does not result in a significant prolongation of treatment time. The reduction in the number of visits to a GK facility for SRS may impact the overall subjective experience, increasing patient satisfaction.