Test Overview
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.
The fundus contains a lining of nerve cells (the
retina), which detects images seen by the clear, outer
covering of the eye (cornea). The
fundus also contains blood vessels and the
optic nerve.
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:
- Detect problems or diseases of the eye, such as
retina problems.
- Help diagnose other conditions or diseases that
damage the eye.
- Evaluate symptoms, such as
headaches.
- Detect other problems or diseases, such as head injuries
or brain tumors.
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
Direct ophthalmoscopy
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. See a picture of a
direct ophthalmoscopic exam.
Indirect ophthalmoscopy
This type of eye exam
gives a more complete view of the retina than direct ophthalmoscopy. It is
usually done by an
ophthalmologist.
- 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
Direct ophthalmoscopy
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.
Indirect ophthalmoscopy
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. See the topic Dilated Eye Exam.
Risks
In some people, the dilating or anesthetic
eyedrops can cause:
Call your doctor immediately if you have severe and sudden
eye pain, vision problems (halos may appear around light), or loss of vision
after the exam.
Results
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.
Ophthalmoscopy
| Normal: |
- All of the structures inside the eye
appear normal.
|
| Abnormal: |
- The
retina is detached.
- Swelling of the
optic nerve (papilledema) is found.
- Optic
nerve damage caused by
glaucoma is found.
- Changes in the retina
(such as hard, white deposits beneath the retina called drusen, or broken blood
vessels called hemorrhages) point to
macular degeneration.
- Damaged blood
vessels or bleeding in the back of the eye is seen. This could be caused by
diseases such as high blood pressure or
diabetes.
-
Cataracts
are
found.
|
What Affects the Test
Reasons you may not be able to
have the test or why the results may not be helpful include:
- Inability to remain still during the
exam.
- Eye problems, such as incomplete pupil dilation, cataracts,
or cloudiness of the liquid inside the eyeball.
What To Think About
- Other eye tests may be done routinely along
with ophthalmoscopy, including vision testing and tonometry testing for
glaucoma. For more information, see the topics
Vision Tests and
Tonometry.
- 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. For more
information, see the topic
Eye Angiogram.
References
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.
Credits
|
By
|
Healthwise Staff |
|
Primary Medical Reviewer
|
Kathleen Romito, MD - Family Medicine |
|
Specialist Medical Reviewer
|
Christopher J. Rudnisky, MD, MPH, FRCSC - Ophthalmology |
|
Last Revised
|
January 9, 2013 |