The retina is a layer of light-sensing cells lining the back of your eye. As light rays enter your eye, the retina converts the rays into signals, which are sent through the optic nerve to your brain where they are recognized as images. The macula is the central portion of the retina responsible for clear, detailed vision which is needed for activities such as reading and driving.
A macular hole is a small break in the macula, located in the center of the eye’s light-sensitive tissue called the retina. A macular hole can cause blurred and distorted central vision.
Most of the eye’s interior is filled with vitreous, a gel-like substance which lies in front of the macula and helps maintain your eyes round shape. As you age, the vitreous gel shrinks and pulls away from the macula, usually with no negative effect on your sight. In some cases, however, the vitreous gel adheres to the macula and is unable to pull away. As a result, the macular tissue stretches. After several weeks or months the macula tears, forming a hole. Less common causes of macular holes include injury or long-term swelling of the macula.
Macular holes often begin gradually. In the early stages of hole formation, your central vision becomes blurred and distorted. If the hole progresses, a blind spot develops in your central vision and impairs the ability to see at both distant and close range. It is important to note that if the macula is damaged, you will not lose your vision entirely. You will still have peripheral, or side vision.
Your ophthalmologist will diagnose a macular hole by looking inside your eye with special instruments. Your ophthalmologist may use a test called Optical Coherence Tomography, or OCT, to scan and examine your retina. OCT uses light waves to reveal specific layers of the retina.
Vitrectomy surgery is the most effective treatment to repair a macular hole and possibly improve vision. The vitreous gel is removed to prevent it from pulling on the retina and replaced with a bubble containing a mixture of air and gas. The bubble acts as a temporary bandage that holds the edge of the macular hole in place while it heals. Surgery is performed under local anesthesia and often on an out-patient basis. You must maintain a constant face-down position for 1 to 2 weeks to keep the gas bubble in contact with the macula.
The position allows the bubble to press against the macula and gradually be reabsorbed by the eye, sealing the hole.
How successful is this surgery?
Maintaining a face-down position is crucial to the success of the surgery. Because this can be difficult for some people, it is important to discuss this with your doctor before surgery. Your doctor can advise you on how to use various pieces of equipment to make this easier for you. You can expect some discomfort after surgery. You will need to wear an eye patch for a short time. You will be prescribed eye drops and be advised when to resume normal activity. DO NOT FLY IN AN AIRPLANE OR TRAVEL AT HIGH ALTITUDES UNTIL THE GAS BUBBLE HAS DISSOLVED. A rapid increase in altitude can cause a dangerous rise in eye pressure. Vision improvement varies from patient to patient. The outcome for vision may depend on the size of the hole and how long it was present before surgery. Vision does not return all the way to normal.
What are the risks of macular hole surgery?
Some of the risks of vitrectomy include: infection of the eye, bleeding of the eye, retinal detachment, high pressure in the eye, poor vision, and accelerated cataract formation. It is important that you discuss the potential risks and benefits of this procedure with your ophthalmologist before making a decision regarding treatment.