This document may be copied for your personal use. One additional copy may be reproduced for archive or to share. The publication must be copied in its entirety and include the copyright notice. Any use or sale for profit is strictly prohibited.
PLEASE READ THIS: The information contained herein is not intended
as a substitute for medical advice and care from qualified, licensed
health care
providers. The reader should regularly consult a physician in matters
relating
to his or her health and particularly with respect to any symptoms that
may
require diagnosis or medical attention. The information is presented
here to
educate and inform and to guide you to an understanding of cause,
prevention as
well as treatment.
---------------------------------------------------------------------
By E. Lawrence Bickford, O.D.
There are two conditions which are often referred to as "the callous on the eye". At first glance, they appear similar, consisting of a raised, often yellowish or yellow-white patch, occasionally with irritated blood vessels, next to the cornea on the "white of the eye".
A very common lesion occurring from damage to the conjunctiva, the thin membrane which lines the sclera ("white of the eye") and the inside of the eyelids. It is often referred to as a "fatty degeneration" of the tissue. The fine, nearly transparent collagen fibers degenerate and are replaced by thicker, yellowish, more durable fibers and sometimes calcium crystals. This causes the elevated, yellow and sometimes glistening whitish area located next to the cornea. Basically, a callous! Often, there are no symptoms and the patient merely complains of the cosmetic concern.
If the area is significantly raised or has a lot of calcium crystals, the conjunctiva becomes further irritated as the eyelid crosses the area. Additionally, dry eye conditions cause even more lid-conjunctiva sensitivity and more symptoms, often resulting in increased yellowing and the appearance of irritated blood vessels.
It is believed that the primary cause of Pinguecula is exposure. We consider exposure to toxic vapors, salt water spray, exposure to the sun (ultraviolet radiation,) and damage to the conjunctiva from insufficient moisture and lubrication (tears) to be the primary causes. Sometimes, the causative factor can be related to computer use, or other intensive near vision activities. We tend to blink less when concentrating on near vision tasks which may contribute to poor tear exchange and dry eye. Pinguecula can appear after only a brief exposure to damaging chemicals or irritation. The tissue damage increases with continued exposure. It might take only a day or two to notice a new Pinguecula but weeks to resolve it.
Treatment
Treatment is to remove the source(s) of irritation and to provide
moisture,
lubrication and nutritional support so that the conjunctiva can heal.
The use of "artificial tears" drops can be helpful. (Products that are
preservative-free or that have "disappearing preservatives" are
best.) Nutritional support, such as antioxidants (vitamins C and
E and carotenoids) and omega 3 and 6 fats (flaxseed and borage oils,
for example) can be effective. Often the
condition can be reversed, if not too far advanced. Rapid response and
intervention in the process results in less tissue damage and more
rapid
healing. Long standing Pinguecula are more difficult to resolve and may
not
respond as well to treatment. (See "what's new" below.)
In many ways, Pterigium have similar causes and symptoms to Pinguecula. But unlike the more simple Pinguecula, this condition is sometimes progressive and does involve the cornea, sometimes causing irreparable scarring and permanent damage. If allowed to continue to grow out onto the cornea, it can affect vision. This is seldom the case today where medical care is available as there is treatment to arrest the growth of the Pterigium.
It is believed that there is an underlying pathological cause to Pterigium. Unlike Pinguecula, the lesion develops a blood supply, is attached to the underlying structures, and grows new tissue which invades the adjacent cornea.
Treatment:
Again, prevention is the best method of treatment. Cosmetic concerns and surface irritation are primary patient complaints. Pterigium are less likely than Pinguecula to resolve with simple self treatment and medical intervention is sometimes necessary.
What's New:New medical treatments for dry eye have recently become available.
which include temporary, removable and permanent puncta plugs (to keep
whatever tears produced from draining out) and topical and systemic
medications, including Restasis. Many "dry eye" drops are now available
without potentially irritating preservatives and in longer-lasting gel
form. Restasis, a cyclosporin medicine, was approved for dry eye
treatment relating primarily to rheumatoid/autoimmune disorders, in
early 2003. Puncta plugs have been around for a while, but the latest
generation are "new and improved".