Loading....
Coupon Accepted Successfully!

Ophthalmology

Open Flashcards

Eyelid

Question
14 out of 17
 

Pterygium is characterized by? (AIIMS May 2009)



A Excessive collagen degeneration of the subconjunctival tissue

B Acute inflammatory reaction of the subconjunctival tissue

C Pseudo vascularization of conjunctiva

D Conjunctival tumor

Ans. A Excessive collagen degeneration of the subconjunctival tissue

(Ref. Basak’s ophathalmology 2nd ed. pg. 106)

Pterygium

1. Pterygium in the conjunctiva is characterized by elastotic degeneration of collagen and fibrovascular proliferation.

1. Ultraviolet-light exposure (e.g. sunlight),

2. low humidity, and dust.

3. 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.

Eyelid Flashcard List

17 flashcards
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
11)
12)
13)
14)
15)
16)
17)