What is a vitrectomy?
Vitrectomy means “removal of the vitreous”. The vitreous is a clear gel that fills the back portion of the eye. Sometimes, a vitrectomy is limited to removal of the vitreous, but usually, the removal of the vitreous is just the first step in the procedure. Other maneuvers are often performed, such as peeling material from the surface of the retina or laser treatment.
How is a vitrectomy performed?
The procedure is done in an operating room, usually under local anesthesia with sedation. The patient is temporarily put to sleep with sedatives administered by vein, and a numbing injection is placed around the eye. The patient is then kept in a “twilight” state — relaxed but sometimes semiconscious. Rarely, general anesthesia is used, putting the patient asleep for the entire procedure with the use of a breathing tube placed in the windpipe.
A small blade is used to place three cannulas in the sclera, in a part of the eye called the pars plana. This is the origin of the full name for this procedure, “pars plana vitrectomy”. The cannulas are like tiny sleeves through which instruments can be placed into the vitreous cavity.
One of the three cannulas is used for the infusion line, which consists of sterile plastic tubing that connects the eye to a bottle of a saline-like solution called infusion fluid. The purpose of the infusion line is to keep the eye “inflated” while the vitreous is removed. Without the infusion line, the eye would shrink up like a deflated balloon with removal of the vitreous.
The other two cannulas are used for instruments. One of the instruments is like a tiny flashlight that allows the surgeon to see inside the eye. The other instrument depends on the type of work being done. At the beginning of the operation, a vitreous cutter (a specialized instrument for removing vitreous) is used. After the vitreous is removed, the vitreous cutter is exchanged for whatever instruments are needed to perform the desired tasks. Sometimes, “chandeliers” — light sources that are placed in the eye through separate tiny holes in the sclera — are used, allowing the surgeon to use both hands at once without having to hold a light source.
The surgeon looks into the eye through a microscope, using specialized lenses that provide an excellent view that allows for delicate maneuvers such as peeling membranes from the retinal surface.
After the procedure is finished, the cannulas are removed. The tiny openings in the sclera are usually self-sealing. Occasionally, the scleral openings leak slightly and need to be closed with suture. These stitches usually cause mild discomfort for several days after surgery, as if there were a bit of sand in the eye. As they dissolve, the discomfort resolves.
A patch is placed over the eye following the operation. The following morning, the patch is removed, the eye is examined, and the patient is placed on eye drops. The eye drops are intended to reduce inflammation, prevent infection, and maximize comfort as the eye heals. They are usually continued for several weeks after surgery.
How much pain should be expected after surgery?
Especially with the advent of sutureless surgery, there is usually no significant pain after a vitrectomy. The eye is sometimes scratchy for a few days after surgery. Rarely, there can be more significant pain, in which case we can prescribe strong pain medication.
How should you expect the vision to recover after surgery?
The visual recovery following vitrectomy surgery is much different from recovery after procedures like cataract surgery. On the first day after surgery, the vision is typically quite blurry, especially if a gas bubble is placed in the eye. Although most of the visual recovery usually happens within a few weeks of surgery, the vision often does not reach its maximum improvement until several weeks or even months after surgery.
What about postoperative positioning?
Sometimes, the eye is filled with a gas bubble or silicone oil (a clear liquid similar in consistency to syrup) at the end of surgery. In that case, the patient will usually be instructed to maintain a certain position for the majority of the waking hours and to sleep in a certain position. Depending on the reason for surgery and the procedure performed, these requirements might last for several days or as long two weeks. Maintaining a specific position 100% of the time is not realistic, but it is important to adhere to the instructions as closely as possible to achieve an optimal result. Usually, it is fine to eat three meals a day (lasting about 30 minutes) in a normal position and to take brief breaks from time to time. Otherwise, it is advisable to spend as much time as possible in the desired position.