• Ophthalmoscope is a test that allows a
health professional to see inside the back
of the eye (called the funds) and other
structures using a magnifying instrument
(ophthalmoscope) and a light source. It is
done as part of an eye examination and
may be done as part of a routine physical
• An instrument used for assessment of
• Posterior eye
• Can also be used for the anterior eye
ophthalmoscope:• Here light source from
the batteries is reflected at
90o using a mirror placed
in the head portion at 45o
angle. The examiner looks
through a hole in the
mirror that is through the
Choosing the appropriate lens:
The structures closer to the ophthalmoscope are best seen using positive
lenses, which are labeled with black letters. The retina comes into focus at the
0 diopter, the cup at 2 red.
Type of 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
examination. 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 health professional know
• In some people, the dilating or anesthetic eyedrops can cause
• Brief episodes of nausea, vomiting, dry mouth, flushing, and
• An allergic reaction
• A sudden increase in pressure inside the eyeball (closed-angle
• Call your health professional immediately if you have severe
and sudden eye pain, vision problems (halos may appear
around light), or loss of vision after the examination
The head of the ophthalmoscope:• The head consists of a
window for viewing the
retina, and one for viewing
the lens numbers and a
wheel for changing them.
Lens numbers are marked in
black (positive) & red
Type of portable Ophthalmoscope:-
STRUCTURE AND OPERATION
diagram of a prior art binocular ophthalmoscope
• Ideally should be examined in a dark room.
• Ask the patient to fix stare at an object.
• Turn on scope and set dial at 0.
• Right with right
• Begin at arms length,should see red reflex.
• Move close until optic disc is visible.
• Turn dial until disc is in focus - +/-
Limitations of direct ophthalmoscopy
• Direct ophthalmoscopy of the anterior eye is a
– Instrument of choice is the slit lamp
– We will cover this later in the year
• Low magnification (2.5x for the anterior eye)
• No stereopsis (3D vision)
• Minimal lighting variability