With increasing age, but also after "sealing" retinal holes or retinal surgery, a membrane can form on the retina. This can lead to a folding of the retina, similar to a cloth that is not ironed. This puckering can cause straight lines to be perceived as distorted. These membranes can also lead to a reduction in visual acuity. The diagnosis can be made by ophthalmoscopy and optical coherence tomography. If the symptoms are severely limiting in everyday life, the membrane on the retina can be removed by a surgical procedure. The procedure involves the removal of the vitreous body (vitrectomy) and the "peeling" of the membrane with fine tweezers. Usually, the procedure results in the distorted lines becoming straight again and usually improves visual acuity. Whether or not an intervention makes sense has to be discussed between the specialist and the patient in our Net Speaking Hour. The improvement in the quality of vision after an operation can take several months.