A slit lamp, which is a specialized magnifying microscope, is used to examine structures of the eye (such as the cornea, iris, vitreous, and retina). The slit lamp is used to examine, treat (with a laser) and photograph (with a camera) the eye. The lens of the eye is normally clear. For this purpose, many doctors use a “slit lamp”.
It is a special microscope and light that allow the doctor to see the eyes in 3D, both inside and out. They will use it together with an ophthalmoscope to look at the back of the eye. The eye doctor may use a microscope called a slit lamp to examine the front of the eye. The microscope focuses a narrow, intense line of light on the eye.
The slit lamp provides an enlarged 3D view of the eye and allows the doctor to detect any minor abnormalities. Used with special lenses placed close to the eye, the slit lamp also provides detailed views of the back of the eye. The slit lamp test is designed for the eyes to tell a story that may indicate the presence of many types of eye diseases and possible vision problems. The slit lamp test is one of the most common procedures in a complete eye exam because it tells the ophthalmologist a lot about the state of eye health and can be used to detect indicators of a wide variety of diseases and conditions, such as cataracts, glaucoma, diabetic and related macular eye disease with age degeneration, including blood disorders and certain types of cancer.
Once you are in the ophthalmologist's exam chair, he or she will place a slit lamp in front of you and ask you to rest your forehead and chin on the supports. Slit lamp tests magnify what is happening on the surface of the eye, on the front, on the inside of the eye and on the important retina at the back of the eye. A slit lamp exam helps the eye doctor see the entire physical structure of the eye from the inside. In addition, when the slit lamp is attached to a special magnifying lens, the doctor will be able to see the retina and optic nerve located at the back of the eye.
During the exam, the doctor will look through the microscope and adjust the light of the slit lamp to see certain parts of the eyes. A slit lamp exam is relatively quick and, to a large extent, painless, although your eye may be full of tears or water and you'll have to resist the urge to blink frequently.