Epiretinal membranes (ERM) are disorders leading to vision loss and metamorphopsia. Vitrectomy with membrane peeling has developed to be the gold-standard in treatment of ERM. ERM can be well visualized with spectral domain optical coherence tomography (SD-OCT).

The aim of the study is to examine ERM and internal limiting membranes (ILM) exzised during routine macular surgery with fourier transformed infrared spectroscopy (FTIR) and compare results to optic coherence tomography (OCT) findings.

Purpose of the present study is to analyse components of ERM and ILM, giving hints for the origin of cells producing ERM. In contrast to electron microscopy, FTIR spectroscopy does not need any chemical fixation of the membranes and therefore structure of components of ERM and ILM are not changed by fixation.

In total, 20 eyes with idiopathic ERM, 10 eyes with lamellar macular hole, 10 eyes with full thickness macular hole and 10 eyes with diabetic ERM will be examined. To our knowledge there are no previous reports about FTIR spectroscopy of ERM and ILM, therefore the study will be performed as an exploratory pilot study.

Inclusion Criteria:

• Idiopathic ERM, lamellar macular holes, full thickness macular holes, diabetic ERM and the indication for surgery (visual symptoms)
• Age 21 and older
• written informed consent for surgery and participation in the study prior to surgery

Exclusion Criteria: - Macular edema due to other reasons than ERM

• Hereditary macular disorders
• In case of pregnancy (pregnancy test will be taken preoperatively in women of reproductive age)

no masking