Inner limiting membrane (ILM) removal has become a standard procedure in idiopathic epiretinal membrane (iERM) peeling over the last 15 years but some entities still respond poorly to surgery, like pseudo-lamellar holes, either in their final visual acuity or metamorphopsia reports. Herein, we propose to investigate the importance of gas injection as a tamponade in every instance of iERM peeling and examine the effect on final visual acuity and oedema by OCT findings.


This study is a four-year prospective/retrospective study including 61 patients that were operated for ILM peeling under slit lamp microscopic control. Patients were either assigned in group 1 (addition of gas at the end of surgery, n=30) or group 2 (no gas, n=31). When gas was injected, patients were asked to respect a prone positioning during 10’/hour for the first 7 days. BCVA was measured in decimals preoperatively and at 12 months after surgery with OCT reports, and then converted in LogMAR. Inclusion criteria were best-corrected visual acuity (BCVA) between 0.5 and 0.2 (LogMAR) with an idiopathic epiretinal membrane (no history of diabetes, retinal vein occlusion, retinal detachment, …). In a next step, iERM were subdivided in different entities based on OCT findings to examine the importance of gas on surgical results.

Effectiveness / Safety:

Preoperative BCVA was comparable between groups (group 1= 0.403 +/- 0.132, group 2= 0.416 +/- 0.103 in LogMAR, p=0.599). Final BCVA was measured at one year and revealed an increased recovery with gas. Especially, anatomic results demonstrated by OCT findings are better after gas injection in some iERM entities.