Premacular membrane
A variety of retinal problems can develop as a result of abnormal oscillatory movements involving the vitreous, the viscid gel which fills the eye. With age, the gel separates, ever so slightly, from the retinal surface, and the intervening space is occupied by a clear, serous-like fluid. Usually, that process creates few, if any, symptoms, other than some floaters of mild severity.
Occasionally, a delicate membrane will develop in the surface of the macular retina as the vitreous separates from the retina (See photograph below) Sites of persistent vitreous attachment can cause distortion of and swelling within the macula. Vitrectomy can become necessary to remove the attachment to the retina and, as a result, regain better function of the macula.