Vitrectomy is performed under local or general anesthesia depending on the complexity of the surgery. Complex cases are usually done under general anesthesia. The surgeon uses a microscope and special lens to get a clear look at the back of the eye. Then, tiny incisions a few millimeters in length are made on the sclera. This is the tough, white fibrous tissue covering the eye.

A fiber optic light source is inserted through an incision and used to illuminate the inside of the eye, and a microscope is suspended over the eye. An infusion line is inserted into one of the incisions, and a clear salt solution is used to replace the volume of removed tissue. This helps maintain the eye’s shape and provide proper eye pressure during the surgery.

While the patient is under anesthetic, special microsurgical cutters are used to remove scar tissue and vitreous tissue.

There are several other procedures that are often performed in conjunction with a vitrectomy. These include:

• Repair of a detached retina. Vitrectomy is used to remove scar tissue that is pulling the retina away from the wall of the eye. This allows the retina to settle and flatten out.
  
  
• Macular hole surgery. This is a procedure to repair a hole in the macula, the tiny oval area made up of millions of nerve cells located at the center of the retina. The macula is the source of sharp, central vision.
  
  
• Macular membrane peel. A peeling away of the membrane covering the macula that can improve vision acuity.

Other techniques that may be employed during a vitrectomy include:

• Laser sealing of blood vessels. A tiny laser called an endophotocoagulator is sometimes used to seal tiny vessels that are leaking blood inside the eye.
  

  

• Insertion of a gas bubble. A small gas bubble may be placed inside the eye to seal a retinal or macular hole. The gas bubble will eventually be absorbed, and replaced by natural fluids.
  
  
• Silicone oil. After a detached retina has been reattached, silicone oil may be used instead of saline solution to fill the eye and keep the retina in position.  Sometimes, air or gas is substituted for silicone oil.

The time needed to complete a vitrectomy depends on whether other procedures are performed. The overall health of the eye also affects how long the surgery will take. On average, the procedure takes at least two hours to complete.

In some cases, vitrectomy is an outpatient procedure. In other situations, the patient may be kept overnight. If both eyes need the treatment, the second vitrectomy is generally performed several weeks later.