Ophthalmoscopy (also called fundoscopy) is a test that allows a doctor to see inside the back of the eye (called the fundus) and other structures using a magnifying instrument (ophthalmoscope) and a light source. It is done as part of an eye exam and may be done as part of a routine physical exam.
There are two types of ophthalmoscopy.
- Direct ophthalmoscopy. Your doctor uses an instrument about the size of a small flashlight with several lenses that can magnify up to about 15 times.
- Indirect ophthalmoscopy. Your doctor uses a small handheld lens and either a slit lamp microscope or a light attached to a headband. Indirect ophthalmoscopy provides a wider view of the inside of the eye and allows a better view of the fundus even if the lens is clouded by cataracts .
Why It Is Done
Ophthalmoscopy is done to:
How To Prepare
No special preparation is needed before having this test.
Your doctor may use eyedrops to widen (dilate) your pupils. This makes it easier to see the back of the eye. The eyedrops take about 15 to 20 minutes to dilate the pupil fully. Your doctor may also use eyedrops to numb the surface of your eyes. Tell your doctor if:
- You or anyone else in your family has glaucoma.
- You are allergic to dilating or anesthetic eyedrops.
You may have trouble focusing your eyes for several hours after the test. You may wish to arrange to have someone drive you home after the test. You also will need to wear sunglasses when you go outside or into a brightly lit room.
Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results may mean. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?).
How It Is Done
This type of exam can be done with or without eyedrops.
- Your eyes may be dilated and you will be seated in a darkened room and asked to stare straight ahead at some distant spot in the room.
- Looking through the ophthalmoscope, your doctor will move very close to your face and shine a bright light into one of your eyes. Each eye is examined separately.
- Try to hold your eyes steady without blinking.
This exam takes a few minutes.
- Your eyes will be dilated and you may be asked to sit upright with your head on a chin rest in a darkened room.
- Your doctor will hold your eye open, shine a very bright light into it, and examine it through a special lens.
- Your doctor may ask you to look in different directions and may apply pressure to your eyeball through the skin of your eyelids with a small, blunt instrument to help bring the edges of your fundus into view.
This exam takes a few minutes.
How It Feels
During direct ophthalmoscopy, you may hear a clicking sound as the instrument is adjusted to focus on different structures in the eye. The light is sometimes very intense, and you may see spots for a short time following the exam. Some people report seeing light spots or branching images. These are actually the outlines of the blood vessels of the retina.
With indirect ophthalmoscopy, the light is much more intense and may be somewhat uncomfortable. Pressure applied to your eyeball with the blunt instrument also may be uncomfortable. After-images are common with this test. If the test is painful, let the doctor know.
When dilating eyedrops are used
Dilating drops may make your eyes sting and cause a medicine taste in your mouth. You will have trouble focusing your eyes for up to 12 hours after your eyes have been dilated. Your distance vision usually is not affected as much as your near vision, though your eyes may be very sensitive to light. Do not drive for several hours after your eyes have been dilated. Wearing sunglasses may make you more comfortable until the effect of the drops wears off. To learn more, see the topic Dilated Eye Exam.
In some people, the dilating or anesthetic eyedrops can cause:
- Brief episodes of nausea, vomiting, dry mouth, flushing, and dizziness.
- An allergic reaction.
- A sudden increase in pressure inside the eyeball (closed-angle glaucoma).
Ophthalmoscopy is a test that allows a doctor to see inside the back of the eye (called the fundus) and other structures using a magnifying instrument (ophthalmoscope) and a light source.
What Affects the Test
Reasons you may not be able to have the test or why the results may not be helpful include:
What To Think About
- Other eye tests may be done routinely along with ophthalmoscopy, including vision testing and tonometry testing for glaucoma.
- Indirect ophthalmoscopy is a more difficult procedure and requires greater skill and more specialized equipment than direct ophthalmoscopy, so it is generally done by ophthalmologists and optometrists.
- Indirect ophthalmoscopy has several advantages over direct ophthalmoscopy:
- It allows better visualization of the inside of the eye when a cataract is present.
- It provides a three-dimensional (3-D) view of the back of the eye, allowing a more detailed view of certain eye conditions (such as growths, optic nerve swelling, or retinal detachment).
- It allows a wider view of the back of the eye.
- If your doctor suspects a problem with the blood vessels in your eye, a test called eye angiography may be done. This test uses fluorescein dye and a camera to photograph blood vessels in the eye. To learn more, see the topic Eye Angiogram.
Other Works Consulted
Chang DF (2011). Ophthalmologic examinations. In P Riordan-Eva, ET Cunningham, eds., Vaughan and Asbury's General Ophthalmology, 18th ed., pp. 27-57. New York: McGraw-Hill.
Primary Medical ReviewerKathleen Romito, MD - Family Medicine
Specialist Medical ReviewerChristopher J. Rudnisky, MD, MPH, FRCSC - Ophthalmology
Current as ofSeptember 9, 2014