Spectral-domain Optical Coherence Tomography of the Eye

Inclusion Criteria: * Age 21 and older * Normal eyes or * Eyes with corneal disease: Subjects that have any of the following conditions 1. Corneal dystrophy or degeneration 2. Corneal scarring 3. Corneal ulcer 4. Corneal injury 5. Keratoconus 6. Patients who had undergone corneal surgery 7. Patients with other corneal disease or - Eyes with retinal disease: Subjects that have any of the following conditions: 1. Diabetic macular edema 2. Cystoid macular edema 3. Age related macular degeneration 4. Retinal vascular disorders (e.g. retinal artery occlusion) 5. Epiretinal membrane 6. Choroidal nevus 7. Macular hole 8. Patients who had undergone retinal surgery 9. Patients with other retinal disease or * Eyes with glaucoma * Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant. AND \- Written informed consent prior to recruitment Exclusion Criteria: Any of the following will exclude a subject from the study: * Patients who are not able to cooperate or with insufficient ability to fixate (tremor, nystagmus) * Pregnancy (pregnancy test will be taken in women of reproductive age before enrolment into the trial)