Changes in each retinal layer and ellipsoid zone recovery after full-thickness macular hole surgery

Abstract

To analyze the changes in each retinal layer and the recovery of the ellipsoid zone (EZ) after full-thickness macular hole (FTMH) surgery. Patients who underwent surgery for FTMH were included. Spectral-domain optical coherence tomography (SD-OCT) was performed preoperatively and postoperatively at 1, 3, 6, 9, and 12 months. A total of 32 eyes were enrolled. Ganglion cell layer, inner plexiform layer, and inner nuclear layer showed significant reductions over time after surgery (P = 0.020, P = 0.001, and P = 0.001, respectively), but were significantly thicker than those of fellow eyes at 12 months postoperatively. The average recovery duration of the external limiting membrane (ELM), outer nuclear layer (ONL), and EZ was 1.5, 2.1, and 6.1 months, respectively. Baseline best-corrected visual acuity (BCVA) (P = 0.003), minimum linear diameter (MLD) (P = 0.025), recovery of EZ (P = 0.008), and IRL thickness (P < 0.001) were significant factors associated with changes in the BCVA. Additionally, axial length (P < 0.001), MLD (P = 0.020), and IRL thickness (P = 0.001) showed significant results associated with EZ recovery. The IRL gradually became thinner after FTMH surgery but was still thicker than that of the fellow eye at 12 months postoperatively. The recovery of ELM and ONL may be a prerequisite for the EZ recovery. The BCVA change was affected by baseline BCVA, MLD, recovery of EZ, and IRL thickness. Additionally, axial length, MLD, and IRL thickness were significantly associated with EZ recovery.

Ellipsoid Zone and External Limiting Membrane-Related Parameters on Spectral Domain-Optical Coherence Tomography and Their Relationships With Visual Prognosis After Successful Macular Hole Surgery

“…BCVA was significantly correlated with axial length and DHI at baseline. Lee et al found that long axial length may impair EZ recovery, resulting in poorer functional visual outcomes (22), which is consistent with our finding of a negative correlation between axial length and BCVA. As no single EZ-related preoperative parameter differed significantly between groups A and B, a larger sample size and measurement of other OCT parameters related to the EZ band are needed in future research investigating the close relationship between the EZ band and photoreceptor function.…”

“…Our study found that the ratio of closed EZ band in Group A was significantly higher than in Group B at 1- and 6-months postoperative visits, showing a positive correlation between EZ band recovery and BCVA, which is consistent with previous studies. In terms of thickness, Lee et al found that BCVA was affected by inner retinal layer thickness, which was in turn significantly associated with EZ recovery ( 22 ). A study by Sevgi et al showed that EZ-RPE thickness at 1-month follow-up in MH patients was significantly correlated with BCVA at 12 months postoperatively ( 23 ).…”

“…Bottoni et al reported that the ELM was the first structure to recover after MH closure ( 9 ). Lee and colleagues demonstrated that ELM and EZ recovery occurred 1.5 and 6.1 months after full-thickness MH, respectively, and all subjects with intact EZ showed intact ELM, indicating that ELM may be a prerequisite for EZ recovery ( 22 ). In our study, the rate of EZ recovery was lower than that of the ELM, and patients with an intact EZ also had an intact ELM, supporting the hypothesis that their recoveries are closely connected.…”

Indistinct retinal outer layers in the walls of the idiopathic full-thickness macular hole - A potential predictive biomarker for surgical outcomes

“…[ 20 ] This is followed by the gradual restoration of EZ with the prerequisite of an intact outer nuclear layer (ONL). [ 21 22 ] ELM is thought to be composed of Muller cells’ terminal processes which surround photoreceptor cells. [ 23 ]…”

Postoperative microstructural re-modelling and functional outcomes in idiopathic full thickness macular hole

“…[ 9 10 ] However, very few studies are available on simultaneous microstructural analysis of all retinal layers and their remodeling influencing structural and functional outcomes. [ 11 ]…”