Epiretinal membrane (ERM) is a pathological phenomenon requiring surgery when vision is altered.

ERM surgery requires ERM peeling, then active internal limiting membrane (ILM) peeling if it is not spontaneously peeled with ERM. Initiation of peeling is very delicate and can lead to micro scotoma when realized with microscopic forceps. The Sweeper is a microscopic tool with a soft silicon tip covered with diamond dust which allows peeling initiation without retina prehension. It may reduce retinal trauma and visual sequelae.

Purpose of our study is to evaluate use of sweeper during 20 ERM surgeries. The investigator will compare microperimetry before surgery versus those after 1 month (M1) and 3 months (M3), and measure difference of number and depths of micro scotoma.

The investigator will note: number of forceps uses if sweeper is inefficient and all areas of sweeper use to correlate them with micro scotoma.

The investigator will evaluate visual and optical coherence tomography improvement after surgery.

Epiretinal membrane (ERM) is a pathological phenomenon that leads to visual loss, visual distortions, central scotoma, and diplopia. No medical treatment is yet available.

ERM surgery requires separation of normal retina and epiretinal membrane. After epiretinal peeling, if internal limiting membrane (ILM) is not spontaneously peeled with ERM, surgeon peels ILM from retina (also named active peeling). Initiation of peeling is very accurate and delicate. Either microscopic forceps or sweeper are used to initiate peeling. Sweeper is a microscopic tool with a soft silicon tip covered with diamond dust which allows peeling initiation without retina prehension. It may reduce retinal trauma and visual sequelae.

ILM active peeling reduces recurrence of ERM and rate of repeat surgery. No visual acuity loss has been found. But 2 studies show increase of micro scotoma at micro-perimetry after active ILM peeling with forceps.

Purpose of our study is to evaluate use of sweeper during 20 ERM surgeries. The investigator will compare microperimetry before surgery versus those after 1 month (M1) and 3 months (M3), and measure difference of number and depths of micro scotoma.

The investigator will note: number of forceps uses if sweeper is inefficient, all areas of sweeper use to correlate them with micro scotoma.

The investigator will evaluate visual and optical coherence tomography improvement after surgery.

Our study doesn't include any intervention while surgeries would be realized with or without study participation. Examinations are non-invasive, usual, and done during usual medical visit without additional visit.

Inclusion Criteria:

• consent,
• adult patient,
• Epiretinal membrane

Exclusion Criteria:

• perimetry impossible

The population concerned corresponds to the major patients consulting in the ophthalmology department at the Nantes University Hospital and presenting an epiretinal membrane and an operative indication.

Patients will be included at the epiretinal membrane surgery programming consultation. No inclusion will be made as part of the emergency.