Optic Nerve of the Human Eye

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Optic Nerve of the Human Eye

• By Sandy McKeever,C.O.T.
• October 2009

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The proper way to evaluate the Optic Nerve.

• 1. Margins Are they distinct and flat or
  elevated?
• 2. Color Is it pink, or a yellowish/pink?
• 3. Cup How to determine the size of the cup.
• 4. Veins and Arteries The veins should be 1/3
  larger than the arteries.

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This is a Direct Ophthalmoscope. The green
button you see is called the rheostat, if pushed
down and to the left, it is on.
Rheostat
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Light aperture
Aperture selection dial
Focusing dial
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Viewing hole
Focus dial display window
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• It is not important that you can precisely
  determine the cup size. It is important to
  determine it the cup is too large and needs a
  consult with the ophthalmologist
• In the picture above note the size of the disc,
  we consider any disc size to be 10 and we
  estimate the cup size within the disc size of 10.
  Looking at the photo above the cup is taking up
  at least ½ of the disc and slightly more than
  that because of its width. Any cup size 5 or
  greater you would want to consider sending the
  patient to an ophthalmologist for Glaucoma
  consultation.
• In addition to that information, you also want to
  make sure that each eye is approximately the same
  cup size. If you find a patient who has one eye
  with a cup size 5 or greater and the other 3 or
  less you would want to consider sending the
  patient to an ophthalmologist for consultation.
  Asymmetric cup sizes are Red Flags.

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Lets start the evaluation from the outside in as
instructed in the earlier slide. 1.Margin
distinct. 2. Color is a yellowish/pink
(normal) 3. The cup size takes up a little less
than ½ of the disc. 4.The veins in deed look at
least 1/3 or more larger than the arteries.
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Looking at the photo to the right it looks out of
focus and blurry. Check your focusing lens dial
on your direct ophthalmoscope. Check your
position away from the patient, you may need to
be closer. Regardless you could still evaluate
the optic nerve. Margins are blurred, but you
can make out the margin. The color is yellow and
pink in areas but certainly not atrophic. Your
cup takes up less than half of your
disc. Arteries are smaller than the veins and the
vein look slightly engorged, but ok.
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In the photo you can certainly see the margin
distantly, finding the cup looks a little
difficult. Evaluate Margin distant Color is
pink-yellowish Cup Looking at the center of the
disc where your veins and arteries are coming
from, just to the left of that you will see a
small area that is slightly lighter in color,
this is your cup and its size is small, nothing
to worry about. Vessels your arteries are
smaller than your veins (normal).
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• In the photo to the right it is a little tricky
  to see if your margin is elevated. One pearl to
  take with you is to always look at all your
  vessels coming from the nerve head. Some vessels
  could appear to be curved and making it appear to
  be two dimensional. Giving the illusion of
  elevation. Notice the vessel at 5 oclock how it
  goes straight across the margin.

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• Evaluate
• Margin distant and not elevated.
• Color is pink
• Cup in taking up more than half the disc and you
  would consider ophthalmology consult for glaucoma
• Vessels arteries are smaller than your veins
  and the veins look slightly engorged.

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As you can tell by now retinal pigment color
comes in many different hues, as well as people.
Evaluate Margin Flat and distant. Color
pink Cup is small and normal Vessels arteries
are smaller than veins
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This is a beautiful picture of the fundus of an
eye. From this picture if you look towards the
right you will see a round, small darken area.
This area is the macula, central vision comes
from this area, also know as the fovea. There
appear to be no abnormalities in or around the
macula. Evaluate Margin flat and
distant Color pink Cup this cup is taking up
most of the disc, much to large, needs further
evaluation Vessels arteries are 1/3 less than
the vein (text book looking).
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In the photo to the right I want to bring your
attention to the area of Hemorrhages at about 9
oclock. Lets evaluate. Evaluation Margin
Indistinct Color pink,yellow,pale,and one spot
red. Cup can not see a cup Vessels Most
arteries appear to be smaller than veins but some
look the same size. This patient needs to be
evaluated by an Ophthalmologist or Neurologist.
This could be a serious condition.
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• Think of this swollen optic nerve as a mushroom.
  (A BAD Mushroom). Notice the elevation the
  vessels have to reach in order to go over the
  margin and into the retina. If you look at your
  vessels at 5, 7,8 and 1 oclock it is obvious how
  elevated this nerve is. Diagnosis Papilledma.
• Evaluate
• Margin ELEVATION, you could stop here and send
  out.
• Color White
• Cup to swollen cant see one.
• Vessels large and engorged.

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• I wanted to show you the illusion of elevation
  and actual elevation of a nerve head. The photo
  from the slide before on the left shows great
  elevation especially looking at your vessels at 5
  and 8 oclock. The vessels in the photo to the
  right looked curved _at_ 1, 3 and 11 oclock giving
  you the illusion of elevation. This is why it is
  so important to look at all the vessels to find
  elevation. So your vessels _at_ 12, 5, 6, 630 9
  and 10 all look straight across the margin.

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Normal red reflex in both eyes
This test is a very good tool for you as a
practitioner, it is quick and easy to perform.
The information you can receive from this test
can easily detect for you possible problems.
Bruckners Test
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• In a dimly illuminated room, face the patient
  from a point about two feet from the patients
  face. Set the aperture dial to the widest
  setting, and select 0 for the focusing power.
  Look through the viewing hole and direct the
  light at a point between the patients eyes.
  Examine the red reflex from each eye, and compare
  the two eyes. If the reflexes are unequal in
  brightness, or if one or both reflexes have black
  spots in them, the patient must be referred for
  an ophthalmologic examination.

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AmblyopiaThe enemy