CPOA Contact Lens Basics 3

Question 1

Which complication is characterized by blood vessels growing into the normally avascular cornea due to contact lens hypoxia?

Accepted Answer

Corneal neovascularization

Answer

Corneal neovascularization (pannus) occurs when the cornea is oxygen-deprived, stimulating blood vessel ingrowth from the limbus.

Question 2

A rigid gas-permeable (RGP) lens that is too flat will typically:

Accepted Answer

Decentrate inferiorly and show excessive movement

Answer

A flat-fitting RGP lens rides on the apex of the cornea and moves excessively, often decentering inferiorly.

Question 3

What does the term 'orthokeratology' refer to in contact lens practice?

Accepted Answer

Using rigid lenses overnight to temporarily reshape the cornea

Answer

Orthokeratology (ortho-k) uses specially designed rigid lenses worn overnight to temporarily flatten the cornea and reduce myopia.

Question 4

Which contact lens design is most appropriate for a patient with irregular corneal astigmatism due to keratoconus?

Accepted Answer

Rigid gas-permeable lens

Answer

RGP lenses vault over the irregular corneal surface and provide a smooth optical surface via the tear lens, making them the preferred option for keratoconus.

Question 5

Giant papillary conjunctivitis (GPC) associated with contact lens wear most commonly affects which ocular surface?

Accepted Answer

Upper tarsal conjunctiva

Answer

GPC is characterized by large papillae on the upper tarsal (palpebral) conjunctiva, often caused by lens deposits or mechanical irritation.

(CPOA) Certified Paraoptometric Assistant Practice Test

(CPOA) Certified Paraoptometric Assistant Practice Test

CPOA Contact Lens Basics 3