Macular Hole surgery is a form of keyhole surgery performed under a microscope, using 3 small incisions (1-2mm in size) in the white of the eye for insertion of very fine instruments. Firstly, the vitreous jelly is removed (vitrectomy), and then a very delicate layer (the inner limiting membrane) is sometimes carefully peeled off the surface of the retina around the hole to release the traction forces that keep the hole open. In complex cases, the inner limiting membrane may be used to fill the macular hole and improve closure. The eye is then filled with a temporary gas bubble, which presses against the hole to help it seal. The bubble of gas blocks the vision whilst it is present, but it slowly disappears over a period of about 2-12 weeks.
[British and Eire Association of Vitreoretinal Surgeons – Macular Hole ]