Laser Surgery of the Eye
Laser surgery has been one of the great advances in treating eye diseases. In most situations, laser surgery helps prevent further loss of sight, but will not provide great improvement in vision. In a few situations, vision may be restored to normal. Your ophthalmologist will discuss the risks and benefits that laser treatment can offer you.
Laser surgery of the eye has several advantages, including no risk of infection from the laser light, the surgeon has great precision and control, and laser surgery can be performed in an outpatient setting, without an overnight hospital stay.
There are two different ways that lasers are used to treat eye diseases:
Thermal lasers
Light is converted to heat when it reaches the eye. The heat is used to:
- Seal blood vessels (veins and arteries) that are bleeding or leaking fluids
- Destroy abnormal tissue, such as a tumor
- Bond the retina to the back of the eye
- Open the eye's filtration system to treat glaucoma
- Create an opening in the iris for treatment of narrow angle glaucoma
Photodisruptive lasers
Light cuts or sculpts the tissue, similar to a knife. The beam of light is used to:
- Cut thin membranes inside the eye that are blocking vision
Ophthalmic Photography
Ophthalmic photography uses specialized equipment to illuminate and make an image of specific structures in the eye. There are different types of ophthalmic photography, based on the different photographic methods.
Fundus Photography
Also called a fundus camera, a retinal camera allows detailed imaging of the back of the eye. Using fine-grained color slide film, a trained photographer can consistently produce detailed photographs in a short time with minimal patient discomfort.
Fluorescein Angiography
A type of fundus photography in which a fluorescent, mineral-based dye, fluorescein sodium, is injected into the patient's arm, and a series of photographs are captured as the dye moves through the blood vessels in the eye. Eye doctors then diagnose the patient's state of eye disease based on particular fluorescence patterns in the photographs.
A fluorescein angiogram is a valuable tool for assessing blood flow in the eye. It is well tolerated by patients of all ages, but it is an invasive procedure with some side effects. The dye turns the patient's urine bright yellow for several hours, and patients with light complexions may look a little jaundiced for a few hours.
Optical Coherence Tomography (OCT)
Using low-powered lasers, the OCT makes a cross-sectional picture of the retina, allowing your eye doctor to more easily determine the state of a retinal disease.
Slit Lamp Photography
A slit lamp bio-microscope is the primary examination instrument for the front of the eye: the cornea, lens, conjunctiva (whites of the eye), and the iris. Every eye exam room has one. An eye doctor or ophthalmic technician uses a slit lamp to check the overall health of the eye. Slit lamp photography is done to document disease-related changes to these structures.
Visual Field Testing
A visual field test measures how much "side" vision you have, determining if you have lost sight from glaucoma and other conditions. Changes in the visual field help to determine if the sight is getting worse and the glaucoma is progressing.
It is a straightforward test, painless and does not involve eye drops. Your head is kept still and you have to rest your chin on a chin rest. Lights are flashed on, and you press a button whenever you see a light. The lights are bright or dim at different stages of the test. Some of the flashes are purely to check that you are concentrating.
Each eye is tested separately, and you should allow 15 to 45 minutes to have the whole test. You will need to bring any glasses you may wear.