Duration of face down positioning following full-thickness macular hole repair: A protocol for a randomized pilot study.

Objective: Full-thickness macular holes (FTMH) are defects in the fovea involving all neural retinal layers. They reduce patients' visual acuity (VA) and impact their quality of life. FTMHs are repaired with pars plana vitrectomy (PPV) with intraocular gas tamponade and post-operative face-down positioning (FDP). There is no consensus regarding the ideal positioning requirements following FTMH repair and there lacks clear guidelines on the topic. While analysis of global practice patterns indicates that between 5-7 days is the most common duration suggested by surgeons, there is significant heterogeneity in surgeon preferences. There is, however, biological plausibility to support minimal or even no FDP following surgery and given the disabling nature of FDP for patients, there is a need to better assess key patient outcomes with different FDP durations. As such, this prospective randomized controlled pilot trial will compare 3-days of FDP to 7-days of FDP following PPV for FTMH.

Methods: This single-centered, parallel-group randomized controlled pilot trial will randomize patients 1:1 following PPV to 3 days or 7 days of FDP. This investigation has been approved by the local ethics board (HiREB # 16100) and has been registered on clinicaltrials.gov (NCT06000111). The primary objective will be focused on assessing the feasibility of a larger trial; this will be determined through an assessment of the recruitment rate, retention rate, completion rate and recruitment time. The secondary outcomes involve assessment of the following patient-important outcomes a) macular hole closure rate, b) best-recorded VA, c) a general quality of life measure and vision-specific quality of life measure, d) patient compliance and e) complication rates. Outcomes will be evaluated at 3 months following surgery.

Discussion: The results of this pilot study will determine the feasibility of a larger-scale trial that will answer a patient important question with clinical equipoise.