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.

Pathophysiology of outer retinal corrugations: Imaging dataset and mechanical models.

This article presents high-resolution swept-source optical coherence tomography (SS-OCT) imaging data used to elaborate a mechanical model that elucidates the formation of outer retinal corrugations (ORCs) in rhegmatogenous retinal detachments (RRD). The imaging data shared in the repository and presented in this article is related to the research paper entitled "Outer Retinal Corrugations in Rhegmatogenous Retinal Detachment: The Retinal Pigment Epithelium-Photoreceptor Dysregulation Theory" (Muni et al., AJO, 2022). The dataset consists of 69 baseline cross-sectional SS-OCT scans from 66 patients that were assessed for the presence of ORCs and analyzed considering the clinical features of each case. From the 66 cases, we selected SS-OCT images of 4 RRD patients with visible ORCs and no cystoid macular edema (CME) to validate the mechanical model. We modelled the retina as a composite material consisting of the outer retinal layer (photoreceptor layer) and the inner retinal layer (the part of the retina that excludes the photoreceptor layer) with thicknesses T o and T i and elastic modulus E o and E i , respectively. The thickness of the outer and inner retinal layers and the relative increase in the length of the outer retinal layer (γ) were measured from the SS-OCT images. Measurements from the SS-OCT images of patients with RRD demonstrated a 30% increase (γ=0.3) in the length of the outer retinal layer and a 400% increase in the thickness of the outer retinal layer (To). Using the mathematical model, Eo/Ei ranged between 0.05 to 0.5 to result in ORCs with a similar frequency to those observed in the SS-OCT scans.