Abstract
Purpose :
To evaluate anatomical differences in recovery of outer retinal layers in eyes treated with two different techniques (ILM peeling vs 360° ILM flap)
Methods :
We enrolled consecutive patients with idiopathic FTMH>450µm who underwent 25G PPV with peeling of ILM(surg.F.B.) or with 360° inverted ILM flap technique(surg.M.C.). Patients with other ocular diseases were excluded. A complete ophthalmologic assessment, including BCVA, slit-lamp biomicroscopy, indirect ophthalmoscopy and SD-OCT(Spectralis, Heidelberg) was performed at baseline, 1, 3, 6 and 12 months after surgery. At OCT, two expert readers evaluated the recovery of ELM, EZ/IZ, ONL and the presence of a visible glial plug at 12 months of follow up. Several Fisher’s test were performed for statistical analysis.
Results :
We retrospectively analyzed 26 patients operated from June2008 to Oct2017. They were split in two groups: the ILM peeling group(n=15) and the ILM flap group(n=11). Patients’ characteristics are shown in table1: no significant differences in age, hole diameter, BCVA at baseline and 12 months were found between the two groups. All holes were closed after first surgery. A glial plug was present in 46,6% and 72,7% of patients operated with the ILM peeling and ILM flap technique, respectively(P=0.24). In the absence of a glial plug(11/26, 42%), ELM was always recovered(100%), while the presence of a plug (15/26, 57%) was associated with a reduced percentage of ELM recovery(66%)(P=0.052). A complete EZ/IZ recovery was easily observed in 9 of 11 patients without glial plug(81%), while it was possible just in 1 of 15 patients(6,6%) with a glial plug(P <0.001). An EZ/IZ recovery was present in 47,6% of cases and only if associated with a complete ELM. In the ILM peeling group, a complete EZ/IZ recovery was observed in 46,7% of cases compared with 27.2% of cases in the ILM flap group(P=0.42). In both groups, the presence of EZ/IZ was associated with a higher final BCVA compared to cases in which the EZ/IZ was not restored, with a mean difference of 0.3(P <0.001).
Conclusions :
PPV with a complete peeling of ILM seems associated with a better recovery of outer retinal layers compared to ILM flap technique. The presence of a glial plug seems to be crucial for a complete restoration of photoreceptors. Other recent works have shown similar findings. The main limit of this study is the little sample size.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.