By
Jonathan Yoken, MD
WHAT
IS THE RETINA?
The retina
is a thin layer of tissue which lines the inside of the eye. Like
the film in a camera, the retina senses the light which enters
the eye, and translates the images into electrical signals which
are then telegraphed to the brain (via the optic nerve). The retina
is one of the most delicate and complex organs of our bodies,
and currently it cannot be replenished or transplanted if it is
damaged.
What is
the macula?
The macula is a specific area of the retina. It is at the center
of the visual field-when looking directly at an object, you are
seeing it with the macula, while the rest of the retina is involved
with peripheral vision. Although it represents only a small fraction
of the total size of the retina-about the size of the capital
letter "O" on this page-the macula is crucial for visually
demanding tasks like reading, driving a car, and color vision.
Diseases of the macula may interfere with "detail vision",
making these activities more difficult. Macular problems can also
cause images to appear distorted, or may cause an area of cloudiness
or darkness to form at the center of the visual field. Fortunately,
many diseases which affect the tiny macula may spare the rest
of the retina, thereby preserving peripheral vision. Therefore,
diseases such as Age Related Macular Degeneration rarely result
in complete loss of sight.
