Healing Mechanisms after Macular Hole Repair Suggests Process of Foveation.

Abstract

To evaluate the long-term healing of the fovea following macular hole surgery in light of the processes known to occur during the maturation of the fovea during childhood, in which there is migration of the inner retinal layers away from and the photoreceptors toward the center of the macula. Consecutive patients with longer than 1 year of follow-up were evaluated with spectral domain optical coherence tomography. The inter-inner nuclear layer distance, which was the separation across the fovea of the midpoints of the inner nuclear layers, and the ONL (outer nuclear layer) to RPE (retinal pigment epithelium) thicknesses were measured. There were 22 eyes of 21 patients, 16 of whom were female; the mean age was 65.6 years. Initially following surgery there was closure of the hole with continuity of the inner and middle layers of the retina across the previous macular hole. Over time, there was a migration of the inner retinal layers away from and movement of the ONL toward the center of the macula. The mean inter-inner nuclear layer distance increased from 352 µm to 549 µm (P=.001) and the ONL-RPE thickness increased from 77 µm to 146 µm (P<.001). The mean logMAR acuity improved 6.5 lines. Healing of a macular hole after surgery appears to recapitulate the development of the macula in childhood. The process of foveation may have evolutionary benefit of optimizing macular function after injury despite the absence of effective replication of the highly specialized, post-mitotic photoreceptors.