During all retina surgeries, the vitreous body (jelly-like substance inside the eye) is removed first, to provide easy access to the retina. The vitreous body is particularly important in regard to embryology but then becomes more and more fluid during the course of life and no longer has any noteworthy function. Removing the vitreous body is also referred to as vitrectomy.
During retina surgery, extremely narrow instruments and lighting components are inserted into the eye through openings only 0.6mm in size.
Note that in many cases, an absorbable gas is injected into the vitreous cavity, to further support the eye during the days/weeks following surgery. This gas is absorbed by the body over days and weeks.
During the first few days following the procedure, the patient is not allowed to be in places, where the altitude exceeds 1,000 meters because this would lead to the gas expanding and a raising of intraocular pressure.