Ophthalmology – MCQ 44 – Effects of contact lens wear.

Contact lens wear is proven to have deleterious effects on the comeal physiology. Which of the following statements is incorrect in connection with contact lens wear?
A. The level of glucose availability in the corneal epithelium is reduced
B. There is a reduction in hemidesmosome density
C. There is increased production of CO2 in the epithelium
D. There is a reduction in glucose utilization by corneal epithelium

Correct answer : A. The level of glucose availability in the corneal epithelium is reduced

Contact lens wear decreases gas exchange across the anterior surface of cornea resulting in hypoxia and hypercapnia. In the hypoxic state there is decrease in glucose utilisation. But there is no decrease in glucose availability as it occurs through the aqueous humour on the posterior surface of cornea. Also, there is decreased epithelial cell adhesion due to decrease in hemidesmosome density.