The procedure is done under local anesthetic as an outpatient in much the same way modern cataract surgery is performed. After the placement of the local anesthetic the patient is positioned under a large microscope. Three tiny wounds are made in the front, white part of the eye a few millimeters away from the colored part of the eye. During the procedure, the eye is maintained in its normal shape by the infusion of fluid. The surgeon views the process using an operating microscope and looking down through the dilated pupil. Light is provided in the eye by a fiber-optic light pipe. Instruments are introduced with which the vitreous gel is removed. Sometimes there is a very subtle, but important layer of vitreous material still lying on the macula which is removed by special techniques. If a person has had cataract surgery, removal of the posterior lens capsule is also performed to prevent needing another procedure in the future that may produce new floaters. The instruments are then removed from the eye, and the tiny wounds usually self-seal but sometimes are sewn closed. The patient wears a patch and shield over the eye for the first 24 hours. The amount of discomfort experienced following the surgery is usually quite minimal. Most vitrectomies for floaters require less than an hour of actual operating time but may involve several hours overall for registration and anesthesia.
The visual results of such surgery are very satisfying with complete resolution of symptoms in over 93% of eyes. For those who still have some symptoms remaining, they are usually very mild. Repeat surgery, if needed, relieves residual floaters.
Vitrectomy provides a definitive cure to floaters, although the surgery is not without risk, albeit quite minimal. If the patient hasn’t had cataract surgery yet, there is a high likelihood that in the next several years a cataract will develop in the operated eye. Such cataracts are removed in the same way as ordinary cataracts as an outpatient under local anesthetic. All the other risks are much less frequent. There is a published 1-2% risk of a retinal detachment developing following surgery for floaters. More than 90% of these detachments are fixable, but require further surgery for the repair. There is a 1 in 10,000 risk of a devastating intraocular infection. There are also lesser risks of transient glaucoma, vitreous and retinal hemorrhage, and macular edema. Modern 25-gauge instrumentation and techniques have helped to greatly reduce the risks of these surgical complications.