Treatment of Vision Disturbances Due to Corneal Irregularities by Trans-epithelial Optical Phototherapeutic Keratectomy (TE-oPTK)

Inclusion Criteria: * Patient presents with topographic irregularly irregular astigmatism and associated quality of vision issues, where TE-PTK would be a more effective treatment than topography-guided ablation or other therapeutic treatment options. Medically suitable for corneal laser refractive surgery. * Calculated residual stromal thickness ≥250 µm. * Subjects should be 21 years of age or older. * Contact lens wearers must stop wearing their contact lenses one week per decade of wear before baseline measurements in case of hard contact lenses and one week before baseline measurements in case of soft contact lenses. * Patient will be able to understand the patient information and willing to sign an informed consent. * Patient will be willing to comply with all follow-up visits and the respective examinations. Exclusion Criteria: * Patient not being able to tolerate local or topical anesthesia * Autoimmune diseases * Sicca syndrome, dry eye * Herpes viral (herpes simplex) infections * Herpes zoster * Diabetes * Pregnant or nursing women (or who are planning pregnancy during the study) * Patients with a weight of \> 135 kg * Any residual, recurrent or acute ocular disease or abnormality of the eye, e.g. * Cataract * Suspected glaucoma or an intraocular pressure \> 21 mm of Hg * Corneal disease * Corneal thinning disorder, e.g. keratoconus, * Pellucid marginal corneal degeneration * Dystrophy of the basal membrane * Corneal oedema * Exudative macular degeneration * Inf…