(2) Color blind or color deficient. The term "color blind" is really less
accurate than "color deficient." A person who cannot distinguish between certain colors
is not completely lacking in color perception. Instead, he sees those colors differently
than the individual with normal color perception. About eight percent of the men in the
United States cannot distinguish between red and green. Four percent of the women in
the United States have the same difficulty. It is very rare to find someone who cannot
distinguish between blue and yellow or who has trouble identifying the color violet.
d. Check Visual Field. The visual field refers to the entire area which the
person can see without changing his gaze. A visual field test determines whether the
retina, optic nerve, and the optic pathways are functioning properly. Conduct this test to
determine the perimeters of the patient's field of vision:
(1) Seat yourself in front of the patient with your face directly in front of and
on the same level as the patient's face. (The distance between you and the patient
should be about two feet.)
Have the patient cover one eye without pressing on it.
Ask the patient to focus on your nose.
(4) Move a pencil or other small object in from the side at 15 degree
intervals and ask the patient to signal when he sees the object. (A person with normal
vision can see a moving object about ninety degrees to the side.) This method will pick
up only large visual field defects.
Repeat the test with the other eye.
e. Check Position and Alignment of the Eyes. Look at the eyes to see if they
are positioned and aligned normally.
f. Check the Eyebrows. Look at the eyebrows. Examine for:
Quantity of hairs in the eyebrows.
Distribution of hairs in the eyebrows.
Scaliness of the skin under the eyebrows.
g. Examine the Eyelids. Look for:
Swellings or edema.
Lesions on the eyelids.