Opthalomology

Question 1

Inner to outer layers of the post. segment of the eye?

Answer 1

• Retina
• Choroid
• Sclera

Question 2

What is astigmistism due to?

Answer 2

Abnormal curvature of the eye -> different refractive power at different axes

Question 3

How is astigmatism corrected?

Answer 3

Cylindrical lens

Question 4

Retinopathy of prematurity is caused by an overgrowth of vessels in the retina linked to increased VEGF
What causes increased VEGF: hypoxia or hyperoxia?

Answer 4

Relative HYPOXIA
- Hyperoxia caused by administration of O2 to the baby causes a cessation of vessel growth and VEGF release
- When O2 is stopped the increased metabolic demands increase and cause a relative HYPOXIA -> stimulating VEGF causing neovascularisation

Question 5

Why are corticosteroids administered to women in preterm labour?
(1) What does this stimulate the realse of in the fetus?
(2) What does then prevent the fetus from developing?

Answer 5

Induces surfactant release thus decreasing the risk of Neonatal respiratory distress syndrome

Question 6

What does scotoma mean?

Answer 6

Visual defect surrounded by a relatively unimpaired field of vision