A vitrectomy is a procedure to improve sight by removing the cloudy, gel-like substance (vitreous humor), and sometimes blood, from the center of the eye. When the vitreous is removed, the eye regains its transparency, allowing light to travel to the retina and restore vision.

In a healthy eye, the vitreous is a clear, gel-like substance that fills the center of the eye and helps give it form and shape. However, problems that affect the back of the eye may require the vitreous to be surgically removed. Retinopathy is the most common cause of vitreous disorders in people with diabetes.

Vitrectomy is performed by making incisions in the sclera (the tough, white fibrous tissue covering the eye) and cutting or suctioning out the vitreous gel. Once this is completed, the surgeon may complete one or more of the following:

• Seal off leaky blood vessels using a laser procedure known as endophotocoagulation
  
  
• Remove scar tissue from the retina
  
  
• Flatten areas where the retina has detached from the eye wall
  
  
• Repair tears or holes in the retina or macula (the central area of the retina responsible for sharp vision)

Vitrectomy can restore vision in some patients, according to the U.S. Centers for Disease Control and Prevention (CDC).

A vitrectomy is a surgical procedure to remove the vitreous (the gel at the center of the eye) when blood and buildup of scar tissue, or detachment of the retina, impair a patient’s vision. Removing this blockage restores transparency and allows light to travel to the retina. In many cases, this can significantly improve vision.

Blood and scar tissue are removed by making incisions in the sclera (the tough, white fibrous tissue covering the eye), then cutting and suctioning out the vitreous gel, which makes up about two-thirds of the eye’s volume.

Once the surgery occurs, a substance, usually a balanced salt solution, is inserted into the eye to replace the vitreous gel. This helps maintain the eye’s shape and restores normal pressure to the eye. As the eye heals over time it secretes aqueous and nutritive fluids, helping to replace the vitreous.

Vitrectomies are performed to:

• Clear the eye of blood and debris
• Remove scar tissue
• Alleviate strain on the retina 

The procedure is often necessary when symptoms related to these disorders become severe enough to obscure light as it passes through the vitreous to the retina. This blockage creates blurred vision for many patients. In some cases, the patient’s vision may be completely obscured.

Objects and substances that may be responsible for this blockage include:

• Blood
• Inflammatory cells
• Debris
• Scar tissue

The vitreous also may be removed when it pulls the retina from its normal position. This is known as a detached retina, and it can lead to permanent blindness if left untreated.

In people with diabetes, an eye disorder called diabetic retinopathy is the most common source of problems with the vitreous. This disease causes an abnormal growth of blood vessels in the retina. These vessels are weak and tend to hemorrhage blood into the vitreous. This blood and scar tissue combine to block the passage of light into the retina, which causes vision to become impaired or completely lost.  

Other conditions that affect the vitreous and can lead to a vitrectomy include:

• Macular hole. 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.
  
  
• Preretinal membrane fibrosis (macular pucker). Scar tissue that has formed on the macula and obscures vision.
  
  
• Bleeding inside the eye (vitreous hemorrhage).
  
  
• Injury or infection.
  
  
• Certain problems related to previous eye surgery.

The success of vitrectomy varies. The earlier the surgery is performed for retinal detachments, the more likely it is to be successful. When the goal is to remove blood from the eye, the prognosis is excellent. However, vitrectomies performed to reattach a detached retina are successful only about half the time, according to the American Diabetes Association. In some patients with recent traction retinal detachment or vitreous hemorrhage, the procedure can restore vision, according to the U.S. Centers for Disease Control and Prevention (CDC).

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.

After the surgery, the eye will be patched. Patients must keep this patch on until removed on the first postoperative day in the ophthalmologist’s office. Anesthesia used during the vitrectomy numbs the eyelids, keeping them from blinking. Patients will usually use antibiotic and anti-inflammatory eye drops after surgery as directed by the physician.

Postoperative swelling on the outside of the eye and around the eyelids often causes discomfort for several days after the surgery. Itchiness and the occasional sharp pain are normal. A physician may suggest an ice compress to reduce soreness. Medication is available to reduce itchiness.

Redness will gradually diminish over time. Some patients may experience slight bleeding or bruising outside of the eye and/or eyelids. This also should diminish over time.

Other post-operative advice for patients includes:

• Wear the plastic eye shield to protect the eye when sleeping for the first week after surgery. Patients should also wear the shield when showering during the first week after surgery.
  
  
• Avoid strenuous activity while the eye heals for up to 10 weeks, including bending, stooping and lifting objects heavier than 5 pounds. All activity should be approved by the physician after surgery.
  
  
• Wear sunglasses after surgery. Patients may be sensitive to light for some time after surgery.

Many patients will begin to notice an improvement in their vision about one week after surgery. However, the time frame may vary from patient to patient.  It takes at least 10 weeks for the eye to fully recover after a vitrectomy.

For some patients with severe visual impairment, improvement may be significant enough to allow them to begin reading or driving again. For others, improvement will be more modest.

Vitrectomy increases the formation of cataracts. Patients should consult with a physician about this risk before deciding whether or not vitrectomy is an appropriate treatment for them.

When vitrectomy is performed to reattach a retina, complications may include:

• Retinal tear
• Recurring retinal detachment
• Cataract
• Infection

Another potential complication associated with vitrectomy is fluid buildup in the clear tissue at the front of the eye (corneal edema).

All of these complications have the potential to temporarily or permanently impair vision. Clinical trials are investigating medication that may prevent or slow the progression of cataracts after vitrectomy.

Preparing questions in advance can help patients have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions about vitrectomy:

1. Is vitrectomy recommended for me because of diabetic retinopathy or another condition?
   
   
2. Do I have any alternatives to vitrectomy? If so, what are the advantages and disadvantages of vitrectomy compared to other procedures?
   
   
3. Who will perform my vitrectomy? What is this doctor’s experience and track record with the surgery?
   
   
4. Is my vitrectomy expected to be an uncomplicated or a complex procedure?
   
   
5. Do I need vitrectomy in one eye or both eyes? If both, how long will I wait before undergoing the second procedure?
   
   
6. What are the expected benefits and possible risks of my vitrectomy? What are my chances that cataracts will form or worsen?
   
   
7. When and where will my surgery take place?
   
   
8. Will it be an outpatient procedure or will it require overnight hospitalization?
   
   
9. What type of anesthesia will be used on me?
   
   
10. How long will my surgery last?
    
    
11. Will I experience pain afterward? If so, what type of medication or other treatment will I receive?
    
    
12. What hygiene measures and other steps should I follow after the surgery? What activity restrictions might I have to observe?
    
    
13. How long will my recovery take?
    
    
14. If problems develop, how soon or late might I experience them?