A retinal examination — sometimes called ophthalmoscopy or funduscopy — allows your doctor to evaluate the back of your eye, including your retina, optic disk and the underlying layer of blood vessels that nourish the retina (choroid). Usually before your doctor can see these structures, your pupils must be dilated with eyedrops that keep the pupil from getting smaller when your doctor shines light into the eye.
After administering eyedrops and giving them time to work, your eye doctor may use one or more of these techniques to view the back of your eye:
- Direct examination. Your eye doctor uses an ophthalmoscope to shine a beam of light through your pupil and to see the back of your eye. Sometimes eyedrops aren't necessary to dilate your eyes before this exam.
- Indirect examination (indirect ophthalmoscopy). During this exam, you might lie down, recline in a chair or sit up. Your eye doctor examines the inside of the eye with the aid of a condensing lens and a bright light mounted on his or her forehead — a bit like a miner's lamp. This exam lets your eye doctor see the retina and other structures inside your eye in great detail and in three dimensions.
- Slit-lamp exam. In this exam your doctor shines the beam of a slit lamp through a special lens into your eyes. The slit lamp reveals a more-detailed view of the back of your eye.
The retinal examination usually takes less than 10 minutes, but it may take several hours for the effects of the dilating drops to wear off. Your vision will likely be blurry, and you may have trouble focusing on near objects. If light bothers you, you may need to wear dark glasses (or sunglasses) for a short time. You may be uncomfortable driving with dilated pupils, so make sure you have transportation after your exam. Depending on what you need to see at work, you might need to wear reading glasses or remove glasses that correct for nearsightedness until the effects of the eyedrops wear off.