[Macular pucker surgery with and without delamination of the internal limiting membrane-a prospective randomized...

There is evidence that additional internal limiting membrane (ILM) removal reduces the recurrence rate after pucker surgery with a similar functional outcome. On the other hand, morphological changes of the inner retinal layers after ILM peeling have been described. The aim of this study was to compare the long-term data after vitrectomy with and without ILM delamination in order to uncover possible differences in morphological and functional results.

In a prospective study of 32 patients with idiopathic epiretinal membrane, 16 patients were randomized into each of 2 groups. Both groups underwent pars plana vitrectomy (ppV) with peeling of the epiretinal membrane. In group 1 no forced additional peeling of the ILM was performed and in group 2 the ILM or ILM residues were additionally removed after staining. The investigated parameters were visual acuity, central retinal thickness (CRT) in optical coherence tomography (OCT), metamorphopsia and surgical complications. The time points of the examinations were directly preoperative, after 1, 3 and 6 months and partly 8.4 years postoperatively.

In group 1 (n = 15) the preoperative mean visual acuity improved from 0.54 logMAR to 0.38 logMAR after 6 months postoperatively (n = 13). Of this group 6 patients could be examined in the long-term course and the visual acuity improved further to 0.32 logMAR after 8 years. The CRT decreased from 473 µm preoperatively to 235 µm in the long-term interval. In group 2 (n = 15) the mean visual acuity preoperatively was 0.47 logMAR and improved 6 months postoperatively (n = 13) to 0.38 logMAR and in the long-term examination (n = 5) to 0.1 logMAR. The CRT in this group decreased from 417 µm preoperatively to 278 µm in the long-term interval. In group 1 one recurrence occurred in the follow-up period, in group 2 none.

The study showed that there was no significant difference in visual acuity and CRT between the two groups neither after 6 months nor after 8 years of follow-up. The observed recurrence in the group without ILM delamination underlines the assumption that additional ILM peeling could reduce the recurrence rate.