Laser surgery uses a very focused beam of light to cut, break down, or destroy tissue. Doctors use laser surgery when medications fail to control vision loss caused by glaucoma. Laser surgery is done more often than conventional surgery for glaucoma. However, repeated laser procedures can lead to scarring.

The major advantages of laser surgery over conventional surgery for glaucoma include:

• Less bleeding.
• Less injury to tissues.
• The ability to do most laser procedures without the person having to be admitted to the hospital.

The most common complication from laser surgery for glaucoma is increased pressure within the eye. The pressure may be normal immediately after laser surgery, but rise sharply within 1 to 4 hours, especially in people with severe glaucoma. Apraclonidine can be used before and after surgery to prevent this complication. Other complications may include:

• A brief period of inflammation of the colored part of the eye (iris).
• Bleeding in the eye.
• Cloudiness of the clear covering (cornea) over the iris. This does not usually last long.
• Blockage of the drainage angle when the cornea and the iris stick together.
• Pain.
• Decreased vision.

Before laser surgery, medication to numb the eye may be applied to the eye directly (topical anesthetic) or injected behind the eyeball (retrobulbar anesthesia). Some people feel a sensation of heat in the eye during laser surgery.

The main disadvantage of laser surgery for glaucoma is that it may not always lower pressure in the eye.