As a matter of fact, the most important factor to decide how long it will take after a vitrectomy surgery is the stuff filled in vitreous chamber. Normally, they are gas,silicone oil or saline water. For the first situation, the time is relatively longer because it spend a long period of time for gas in being absorbed, which usually is 1 to 2 moths.For the rest, it takes just 2 weeks or so to recover partial vision. However, no matter what kind of stuff you get, the essential tips is prevent your frail eyes from infection, which can lead to extensive damage. Accordingly, see a doctor to make sure nothing is strange at regular time, and you will see the changes soon.