Medical Edge Newspaper Column

A Rare Complication of Eye Surgery

March 5, 2007
Dear Mayo Clinic:
About a year ago, I had cataract surgery on my left eye for glaucoma. This laser operation caused hemorrhaging of a blood vessel and blindness in that eye. Is there a way to remove the blood so I could see again? -- Issaquah, Wash.

Answer:
Laser therapy is commonly administered as an outpatient treatment both for glaucoma and secondary cataracts, which are two separate conditions. The glaucoma procedure, a trabeculoplasty, shrinks part of the trabecular meshwork -- a sieve-like system of spongy tissue. This helps ocular fluid drain more easily from the eye, reducing the high intraocular pressure that damages the optic nerve in untreated glaucoma.

Laser is also used to treat an "aftercataract," which sometimes forms in a replacement plastic lens implant months or years after the initial cataract was removed. The laser beam creates an opening in the clouded area of the implant, allowing clear images to reach the retina.

Cataract surgery does not treat glaucoma, and glaucoma surgery does not remove cataracts, but because both are relatively brief outpatient procedures they are sometimes combined, which was probably done in your case.

The most likely explanation of your problem is that your eye suffered a hemorrhage following the glaucoma surgery. Low eye pressure may have caused a blood vessel to stretch and burst, resulting in a hemorrhage between the retina and the back wall of the eye. Small hemorrhages may have minimal effects, but large hemorrhages result in severe vision loss. Surgery to remove the blood clot is sometimes performed within the first two weeks, though often the blood will resorb spontaneously. Still, many patients have significant visual loss that cannot be repaired.

Another possible reason for your vision loss is that a blood vessel within either the retina or optic nerve became blocked -- a "stroke" of the eye. There is no way to restore the obstructed circulation or recover lost vision; your main goal if this was the cause should be to prevent further strokes. This means undergoing thorough medical evaluations -- including blood pressure measurement, blood tests for cholesterol and triglycerides, and ultrasound tests of the carotid artery and heart (echocardiogram); and possibly taking anticoagulants daily, such as aspirin or warfarin, under your doctor's care.

Severe vision loss following either cataract or glaucoma surgery is an uncommon complication, though this fact may give you little comfort. While it is unlikely that anything can be done to restore the vision in your left eye, you should routinely consult with an ophthalmologist to safeguard your remaining vision.

-- Michael W. Stewart, M.D., Ophthalmology, Mayo Clinic, Jacksonville, Fla.