The slit-lamp examination looks at structures that are at the front of the eye. The slit-lamp is a low-power microscope combined with a high-intensity light source that can be focused to shine as a slit beam.

While you are seated in the examining chair, the instrument is placed in front of you and you rest your chin and forehead on a support to keep your head steady. Your eyes are then examined through the biomicroscope. A fine strip of paper that is stained with an orange-colored dye (fluorescein) may be touched to the side of your eye. The dye stains the tear film on the surface of the eye to help with the examination. The dye rinses out of the eye with tears.

After this examination, drops may be placed in your eyes to dilate the pupils. The drops take about 15 to 20 minutes to work. The examination is then repeated, allowing the back of the eye to be examined.

No special preparation is necessary for this test.

Your eyes will be sensitive to light for a few hours after the exam if dilating drops are used.

The test is used to examine the eyelids, the sclera, conjunctiva, iris, lens, and the cornea.

Structures in the eye are found to be normal.

The slit lamp exam may detect many diseases of the eye, including:

• Cataract
• Corneal injury
• Macular degeneration
• Presbyopia
• Retinal detachment
• Retinal vessel occlusion
• Retinitis pigmentosa
• Sjogren syndrome
• uveitis

The dilating drops may cause increased pressure in the eye with nausea and pain. This is very rare, but you should IMMEDIATELY return to your doctor's office if you experience either of these symptoms.