Title: Posturing in Macular Hole Surgery
Funder: Department of Health and Social Care

Abstract: Background: Idiopathic macular holes are an important cause of blindness. They have an annual incidence of 8 per 100,000 individuals [1], and prevalence of 0.2 [2] to 3.3 [3] individuals per 1000 depending on the demographic characteristics of the population studied and occur significantly more frequently in adults aged 75 years or older [2] Macular holes can have a devastating impact on quality of life and independence. Macular holes can be repaired by surgery to release the tractional forces and an injection of a temporary bubble of gas into the eye to promote hole closure. Following surgery, individuals may be advised to maintain a face-down posture for up to 10 days with the aim of increasing the probability of successful hole closure by maintaining contact of the gas bubble with the macular hole, and therefore reducing the need for further surgery. Face-down posturing can be an arduous task, associated with significant adverse effects and its value is unproven. A recent Cochrane review [4] highlighted the need for an appropriately designed, adequately powered randomised controlled clinical trial to determine with confidence the value of advice to posture face-down. Aim: The aim of the proposed research is to determine whether advice to posture face-down following surgery for macular holes is more effective that sitting, and thereby reduces the need for further surgery. Plan of Investigation: This will be a multicentre interventional, comparative randomised control trial comparing advice to posture face-down with advice to posture seated. The results of our pilot RCT [5] has demonstrated the feasibility and the number of subjects required. We will recruit 192 patients having surgery for large macular holes (>400 &micro;m). Eligible candidates will be approached by the clinical team, provided with information about the trial and invited to participate. They will be given time to consider their decision and the opportunity to ask questions. Should they decide to participate they will be asked to sign the consent document on the day of surgery. Patient will formally enter the trial immediately following uncomplicated surgery when the will be randomly allocated (in a 1:1 ratio) to one of the 2 treatment arms: Face-down posturing: Patients will be advised to maintain a face-down position for at least 8 hours a day intermittently while awake (at least 50 minutes in every hour) for 5 days following surgery, or Sitting: Patients will be advised to sit in a reading position for at least 8 hours a day intermittently while awake (at least 50 minutes in every hour) for 5 days following surgery The primary outcome will be successful closure of the macular hole, 3 months following surgery, as determined by masked assessment of optical coherence tomography (OCT) scans. This was the outcome measure used in our pilot [5] and also that of the Cochrane review [4]. No comments have been received to our review suggesting that an alternative should be considered which lends weight to it being the most relevant outcome. Hole closure is directly relevant to patients because it is essential for a favourable impact on sight and determines whether further surgery is required. Secondary Outcomes are further surgery for macular hole; best-corrected visual acuity (BCVA) at 3months; and patient quality of life at 3 months using the National Eye Institute Visual Function Questionnaire (VFQ-25) to investigate the impact of face-down posturing and visual outcome on their health and wellbeing. Benefit to Patients: The trial will benefit patients by providing reliable information on the value of posturing following surgery for large macular holes, thereby enabling them to make an appropriately informed choice about the management of their condition.

Lay abstract: Macular hole is a blinding condition in which a hole develops in the central part of the retina, which is the layer of light-sensitive of nerves in the eye. The condition causes sight loss in approximately 2 in every 1000 individuals and can have a devastating impact on quality of life and independence. The condition is believed to result from pulling on the retina by the vitreous gel that fills the eye; it is treated by surgical removal of the vitreous gel to relieve these forces, and injection of a gas bubble to promote closure of the hole. Following surgery, patients may be advised to maintain a face-down position (with the eyes directed straight down) for up to 10 days with the aim of improving the likelihood of successful hole closure by maintaining contact of the gas bubble with the macular hole. However, face-down posturing can be uncomfortable and we do not know if it is actually required to ensure a successful outcome. The aim of the proposed research is to determine the value of advice to posture face-down following surgery for large macular holes. We will perform a trial to compare the success of surgical repair in 96 people advised to posture face-down for 5 days (8 hours per day) with the outcome in 96 people advised only to sit in a reading position for a similar period. The research team combines the strengths of experienced eye specialists with the expertise of the Pragmatic Clinical Trials Unit, and the active involvement of patients to ensure that the trial addresses their needs. The trial will benefit patients by providing reliable information on the value of posturing following surgery for large macular holes, thereby enabling them to make an appropriately informed choice about the management of their condition.

Research activity codes: 6.4 SURGERY
Health categories: EYE