Laser surgeries have become important in the treatment of different eye problems and diseases.
During the laser surgery, the eye is numbed so that there is little or no pain. The eye doctor then holds a special lens to the eye. The laser beam is aimed into the eye, and there is a bright light, like a camera flash.
Laser surgery is still surgery, and can carry some risks. Some people experience a short-term increase in their intraocular pressure (IOP) soon after surgery. In others who require YAG CP (Cyclophoto-Coagulation) surgery, there is a risk of the IOP dropping too low to maintain the eye’s normal metabolism and shape. The use of anti-glaucoma medication before and after surgery can help to reduce this risk.
Laser Peripheral Iridotomy (LPI)
For the treatment of narrow angles and narrow-angle glaucoma.
Narrow-angle glaucoma occurs when the angle between the iris and the cornea in the eye is too small. This causes the iris to block fluid drainage, increasing inner eye pressure. LPI makes a small hole in the iris, allowing it to fall back from the fluid channel and helping the fluid drain.
Argon Laser Trabeculoplasty (ALT)
For the treatment of primary open angle glaucoma (POAG).
The laser beam opens the fluid channels of the eye, helping the drainage system work better. In many cases, medication will still be needed.
Usually, half the fluid channels are treated first. If necessary, the other fluid channels can be treated in a separate session another time. This method prevents over-correction and lowers the risk of increased pressure following surgery.
Argon laser trabeculoplasty has successfully lowered eye pressure in up to 75% of patients treated.
Selective Laser Trabeculoplasty (SLT)
For the treatment of primary open angle glaucoma (POAG).
SLT uses a combination of frequencies that allow the laser to work at very low levels. It treats specific cells “selectively,” leaving untreated portions of the trabecular meshwork intact. For this reason, it is believed that SLT, unlike other types of laser surgery, may be safely repeated many times.
Neodymium: YAG laser cyclophotocoagulation (YAG CP)
An alternative to filtering microsurgery that is typically used later in the treatment algorithm. This surgery destroys part of the ciliary body, the part of the eye that produces intraocular fluid. The procedure may need to be repeated in order to permanently control glaucoma.
There is a slight stinging sensation associated with LPI and ALT. In YAG CP laser surgery, a local anesthetic is used to numb the eye. Once the eye has been numbed, there should be little or no pain and discomfort.
Glaucoma laser surgeries help to lower the intraocular pressure (IOP) in the eye. The length of time the IOP remains lower depends on the type of laser surgery, the type of glaucoma, age, race, and many other factors. Some people may need the surgery repeated to better control the pressure IOP.
In most cases, medications are still necessary to control and maintain eye pressure. However, surgery may lessen the amount of medication needed.
In general, patients can resume normal daily activities the next day after laser surgery.
The procedure is usually performed in an eye doctor’s office or eye clinic. Before the surgery, your eye will be numbed with medicine. Your eye may be a bit irritated and your vision slightly blurry after the surgery. You should arrange a ride home after your surgery.
There is a small risk of developing cataracts after some types of laser surgery for glaucoma. However, the potential benefits of the surgery usually outweigh any risks.
There is a common myth that lasers can be used to remove cataracts; this is not the case except in experimental studies. After a cataract has been taken out with conventional cutting surgery, there often remains an outer membrane lens capsule. This membrane can slowly thicken and cloud vision, just as the cataract did. Laser surgery can open this membrane, helping to clear vision without an operation. This laser procedure is called a capsulotomy.
It is important to discuss all of your questions or concerns about laser surgery with your eye doctor.
The information about Glaucoma Surgery on our website has been provided by the Glaucoma Research Foundation.
My eye doctor wants to perform a laser iridotomy on my eye because I have narrow angles. I don’t have glaucoma, so why do I need to have this procedure done?
Dr. Stamper: Narrow angles may be a precursor to angle closure glaucoma, the kind of glaucoma that can have a sudden, painful onset or a slow unrelenting downhill course.
The best time to prevent the damage that angle closure glaucoma can cause is to treat it with a laser iridotomy before the actual disease sets in. This is preventative medicine at its best.
Although not everyone with narrow angles actually develops glaucoma, careful evaluation of the angle structure can identify who is at greatest risk. The angle structure is determined by an examination called gonioscopy which is performed with a special contact lens called a gonioprism.
It sounds as if your doctor is trying to save you from the risk of acute angle closure glaucoma. A more detailed discussion of this condition and laser iridotomy can be found in the Glaucoma Research Foundation’s excellent booklet, Understanding and Living With Glaucoma
Robert L. Stamper, MD is a Director of Glaucoma Service at University of California, San Francisco, and a member of the Glaucoma Research Foundation Board of Directors.
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