According to the Free Dictionary, a vitrectomy is: “The surgical removal of the vitreous (transparent gel that fills the eye from the iris to the retina).” The vitreous is then replaced with saline. The saline applies the same pressure that the vitreous does. This prevents the eye from collapsing.

Machine Brief:

OPTION #1: vitrectomy= VIT/REK/TO*EM
OPTION #2: vitrectomy= VIT/REK/TO*IM