context: It's a type of eye operation. A doctor removes the vitreous, a jelly-like fluid inside your eye, and replaces it with a saline solution. For you to see, light has to pass through your eye and reach your retina, the bundle of tissue at the back of your eye that senses light. It sends the information to your brain. Various diseases can cause fluid in the vitreous to cloud, fill with blood or debris, harden, or scar. This can keep light from reaching your retina properly and cause vision trouble. Removing and replacing the fluid may solve or improve the problem. Sometimes the retina pulls away from the tissue around it. Your doctor could do a vitrectomy to make it easier to get to your retina and repair it. It can also give your doctor access to your macula, which lies at the center of your retina and provides sharp central vision. A hole in it can result in blurry vision. With the vitreous fluid gone, it's easier to fix. Some other problems vitrectomy can treat include: Damaged blood vessels in your retina Infections inside your eye Serious eye injuries Wrinkles in your retina (macular pucker) Your doctor may also suggest the procedure to treat specific problems after cataract surgery. Your ophthalmologist (an eye specialist) can tell you if there are specific things you need to do to prepare. You can ask: Will I need to stay overnight in a hospital, or will I go home the day of the surgery? Do I need to stop taking certain medications beforehand? Should I avoid food and drinks before surgery, and if so, how long before? What are my anesthesia options? How long do you expect the surgery to take? It's likely the doctor will look again at your eye before surgery using special tools and a light. They may need to dilate your eyes. They might want to do an ultrasound on your eye to look more closely at your retina. A vitrectomy can take anywhere from one to several hours, depending on what condition you're treating. It may be just one in a series of procedures to repair a problem. You'll have the option to stay awake and use numbing drops or shots in your eye. Or you might get general anesthesia -- medicine that helps you go to sleep during surgery. To do the procedure, your doctor will: Make a cut in the outer layer of your eye Cut through the white part of your eye, called the sclera Remove the vitreous fluid with a needle Remove any scar tissue or debris in your eye Once the fluid is gone, your doctor will make any other repairs your eye needs. They might have to inject a gas bubble into your eye to keep your retina in place. The bubble will go away slowly on its own. Before they're done, the doctor will fill your eye with saline. They may use silicone oil instead. If so, you'll need an operation later to get it out. You might get stitches to close up the cuts in your eye, but most people don't need them. Your doctor will put antibiotic ointment on your eye and cover it with a patch. Plan to have someone take you home after your surgery. Once you get there, you may need to hold your head in a certain position to help keep the gas bubble in your eye in the correct place to support your retina. Your eye will be red and sore, and your vision won't be great until the gas is gone. Don't fly above 2,000 feet until the gas bubble has dissolved fully. The increased air pressure could cause problems in your eye, including vision loss. The doctor will give you antibiotic drops to help prevent an infection in your eye. If your eye feels sore, you can take over-the-counter pain relievers. Your doctor will want to check your eye after the surgery. This follow up might happen as soon as the day after the procedure. Vitrectomy surgeries are typically successful. It's rare to have a complication. Your outcome will depend on the condition of your eye and the work that needs to be done to repair it. Still, every surgery comes with risks and possible complications. After a vitrectomy, there is a chance you might get: Cataracts Raised pressure inside the eye More bleeding in your vitreous Retinal detachment Infection Problems moving your eyes Damage to your eye's lens Call your doctor right away if: Your vision starts to go away You have severe pain, swelling, or redness around your eye You have discharge from your eye You see floaters or flashes of light These can be signs of more serious problems that your doctor needs to check and treat.