Megan Pterygium is a benign tumor growth that occurs within the conjunctiva of the eye. It most commonly grows on the nasal side of the sclera. Pterygium is thought to develop based on exposure to ultra-violet light, low humidity, wind, and dust, but the exact cause is unknown. It is known to occur more commonly near the equator, and it is twice as likely to develop in men than in women.1
Etiology:
Kevin Tsai
It is believed that ultra-violet light is a factor in causing the fibrous and vascular changes in the exposed conjunctiva, which gradually grows onto the cornea. If pterygium advances enough to the center of cornea it will obviously threaten vision. This growth is seen mostly in people that have been outdoors for a long time, especially in equator regions (e.g. farmers).2
Signs & Symptoms:
Erin While pterygium may cause no symptoms other than appearance, the following are a few symptoms that may be associated with it:3
Redness and inflammation
Burning
Gritty feeling
Itching
Sensation of a foreign object in the eye
Blurred vision
Diagnostic Procedures:
Spencer Although there are not many diagnostic procedures to confirm for Pterygia, there are a few different things that a physician can assess and check for to help diagnose:4
Visual Acuity Test - This test can measure your ability to see small letters on a chart from about 14-20 feet away.
Slip Lamp Examination - This procedure uses a bright lamp with magnification to examine the eye.
Corneal Topography – This is a computerized test that maps the changes to the curvature of the cornea on the eyeball.
Photo Documentation – A photograph of the eye is taken to record and maintain a track record of the progress in the eye.
Histology:
Pablo Squamous cell carcinoma. Histologically, pterygium development resembles actinic degeneration of the skin5
Lymph node drainage:
Becky
Benign pterygiums typically do not spread to other parts of the body.6
Metastatic spread:
Adam Pterygium is a benign tumor, and does not metastasize to other parts of the body.6
Below is a schematic presentation of the 3 stages of pterygium progression. It is advisable that before ptregium advances to stage three, an excision be performed, otherwise an excision and corneal graft may be required.2
2
Radiation side effects:
Erin Radiation therapy side effects that may be seen (although many are very rare) are the following:8
Ptosis - impaired or dim vision
Symblepharon - adhesion of the eyelid to the eyeball
Cataracts
Endophthalmitis - swelling within the eyeball
Frequently, little to no complications are seen after radiation therapy.8
Prognosis:
Spencer Depending on the condition of Pterygium, the prognosis can differ slightly. Although there is a slight risk of permanent vision loss and blindness, most cases (especially with new age technology) can completely resolve the condition, with better than 85% success rates.9 Most of the time moderate pterygium has no symptoms and therefore doesn’t need to be treated with surgery.
Treatments:
Pablo There are different choices regarding the treatment of Pterygium.
Eye drops may be given to the patient to help with the discomfort produced by such condition. In these cases the patient is usually only monitored by an ophthalmologist.
Surgery is the treatment of choice. Excision combined with conjuctival autograft.
Radiation therapy is used to help prevent any recurrence. Strontium-90 is an isotope used for the treatment of this condition.10
TD 5/5:
Becky v Brain—4500—Necrosis11 v Ear—3000—Otitis v Eye lens—1000—Cataract v Optic chiasma—4500—Blindness v Optic nerve—5000—Blindness v Retina—4500—Blindness
Vonkadich AC. Overview of radiobiology. In: Washington CM, Leaver D, eds. Principles and Practice of Radiation Therapy. 3rd ed. St. Louis, MO: Mosby-Elsevier; 2010: 57-85.
Pterygium is a benign tumor growth that occurs within the conjunctiva of the eye. It most commonly grows on the nasal side of the sclera. Pterygium is thought to develop based on exposure to ultra-violet light, low humidity, wind, and dust, but the exact cause is unknown. It is known to occur more commonly near the equator, and it is twice as likely to develop in men than in women.1
It is believed that ultra-violet light is a factor in causing the fibrous and vascular changes in the exposed conjunctiva, which gradually grows onto the cornea. If pterygium advances enough to the center of cornea it will obviously threaten vision. This growth is seen mostly in people that have been outdoors for a long time, especially in equator regions (e.g. farmers).2
While pterygium may cause no symptoms other than appearance, the following are a few symptoms that may be associated with it:3
Although there are not many diagnostic procedures to confirm for Pterygia, there are a few different things that a physician can assess and check for to help diagnose:4
Squamous cell carcinoma.
Histologically, pterygium development resembles actinic degeneration of the skin5
Benign pterygiums typically do not spread to other parts of the body.6
Pterygium is a benign tumor, and does not metastasize to other parts of the body.6
Grade T1: Atrophic pterygium (episcleral vessels are unobscurred)
Grade T2: Intermediate pterygium (episcleral vessels partially obscured)
Grade T3: Fleshy Pterygium (episcleral vessels totally obscured)7
Below is a schematic presentation of the 3 stages of pterygium progression. It is advisable that before ptregium advances to stage three, an excision be performed, otherwise an excision and corneal graft may be required.2
Radiation therapy side effects that may be seen (although many are very rare) are the following:8
Frequently, little to no complications are seen after radiation therapy.8
Depending on the condition of Pterygium, the prognosis can differ slightly. Although there is a slight risk of permanent vision loss and blindness, most cases (especially with new age technology) can completely resolve the condition, with better than 85% success rates.9 Most of the time moderate pterygium has no symptoms and therefore doesn’t need to be treated with surgery.
There are different choices regarding the treatment of Pterygium.
v Brain—4500—Necrosis11
v Ear—3000—Otitis
v Eye lens—1000—Cataract
v Optic chiasma—4500—Blindness
v Optic nerve—5000—Blindness
v Retina—4500—Blindness