Pterygium: Difference between revisions
No edit summary |
|||
| Line 1: | Line 1: | ||
'''For patient information click [[{{PAGENAME}} (patient information)|here]]''' | |||
{{Editor Help}} | {{Editor Help}} | ||
| Line 6: | Line 8: | ||
ICD9 = {{ICD9|372.4}} | | ICD9 = {{ICD9|372.4}} | | ||
}} | }} | ||
[[Image:Pterygium.jpg|thumb|Pterygium removal surgery]] | [[Image:Pterygium.jpg|thumb|Pterygium removal surgery]] | ||
Revision as of 15:55, 20 January 2010
For patient information click here
Please Take Over This Page and Apply to be Editor-In-Chief for this topic: There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us [1] to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.
Template:DiseaseDisorder infobox
Pterygium usually refers to a benign growth of the conjunctiva. Alternately, it refers to any winglike triangular membrane occurring in the neck, eyelids, knees, elbows, ankles or digits (J Pediatr Orthop B 2004, 13:197-201). An example is popliteal pterygium syndrome, which affects the legs. The term comes from the Greek word pterygion meaning "wing".
When associated with the conjunctiva, a pterygium commonly grows from the nasal side of the sclera. It is associated with, and thought to be caused by ultraviolet-light exposure (e.g. sunlight), low humidity, and dust. The predominance of pterygia on the nasal side is possibly a result of the sun's rays passing laterally through the cornea where it undergoes refraction and becomes focused on the limbic area. Sunlight passes unobstructed from the lateral side of the eye, focusing on the medial limbus after passing through the cornea. On the contralateral side, however, the shadow of the nose medially reduces the intensity of sunlight focused on the lateral/temporal limbus.[1]
Pathology
Pterygium in the conjunctiva is characterized by elastotic degeneration of collagen and fibrovascular proliferation. It has an advancing portion called the head of the pterygium, which is connected to the main body of the pterygium by the neck. Sometimes a line of iron deposition can be seen adjacent to the head of the pterygium called Stocker's line. The location of the line can give an indication of the pattern of growth. As it is a benign growth, it requires no treatment unless it grows to such an extent that it covers the pupil, obstructing vision. Some patients may also choose surgery if the growth becomes too unsightly. The exact cause is unknown, but it is associated with excessive exposure to wind, sun, or sand. Wearing protective sunglasses with side shields and/or wide brimmed hats and using artificial tears throughout the day may help prevent their formation or stop further growth. For surfers and other water-sport athletes, they should wear eye protection that block 100% of the UV rays from the water.
Occasionally it is found as an incidental finding in middle aged patients who spend a lot of time in the sun. Pterygiums are also among younger men and women who surf, wakeboard, and kiteboard due to excessive exposure to UV rays bouncing off of the water. Skiiers and snowboarders protect their eyes on the snow so athletes participating in water sports also need to take heed of the UV rays and protect their eyes.
Treatment
While patients can be symptomatically treated with artificial tears, no reliable medical treatment exists to reduce or even prevent pterygium progression. Definitive treatment is achieved only by surgical removal. Long term follow up is required as pterygium may recur even after complete surgical correction.
See also
External links
- Facts About the Cornea and Corneal Disease The National Eye Institute (NEI)
References
- ↑ Coroneo, MT (November 1993). "Pterygium as an early indicator of ultraviolet insolation: a hypothesis". Br J Ophthalmol. 77 (11): 734–9. PMID 8280691.