Factors Associated With Persistent Subfoveal Fluid and Complete Macular Hole Closure in the PIONEER Study

PURPOSE. To investigate preoperative and intraoperative factors associated with persistent subfoveal fluid in surgically closed macular holes (MHs). METHODS. This was a prospective consecutive case series of eyes undergoing surgical repair for full-thickness MH in the PIONEER study, a prospective intraoperative optical coherence tomography (OCT) multisurgeon single-center study. Thirty-seven eyes (36 patients) with surgically closed MH were studied. Quantitative OCT analysis was performed including intraoperative MH area, volume, ellipsoid zone to retinal pigment epithelium (EZ-RPE) height, extent of subretinal hyporeflectivity (SRHR), and the amount of postoperative subfoveal fluid. RESULTS. Persistent subfoveal fluid was identified in 58% of eyes at 2 weeks following surgery. The mean time to two-line improvement in visual acuity was greater in eyes with persistent subfoveal fluid (P = 0.03). Final visual acuity did not correlate with the initial presence of fluid. Two intraoperative factors following internal limiting membrane (ILM) peeling were associated with the formation of persistent subfoveal fluid: EZ-RPE height and SRHR width (P < 0.01). These were both negatively correlated with amount of postoperative subfoveal fluid (P = 0.028 and 0.04, respectively). CONCLUSIONS. Persistent subfoveal fluid following MH surgery is a common finding that appears to delay visual recovery but not effect final visual outcome. The incidence of persistent subfoveal fluid appears to be related to intraoperative alterations after ILM peeling in the outer retinal architecture (e.g., increased EZ-RPE height and SRHR width). This finding suggests a novel mechanism for facilitating MH closure through ILM peeling (e.g., altering photoreceptor/RPE adherence and increasing retinal mobility that allows for complete hole closure).