Advanced Cornea Quiz

Q1. Why can corneal edema reduce visual acuity?

• Edema increases lens accommodation
• Edema closes the optic canal
• Edema increases the number of retinal rods
• Hydration disrupts the ordered stromal arrangement needed for transparency

Q2. Why can significant corneal endothelial cell loss lead to persistent edema?

• Reduced endothelial pump capacity allows excessive stromal hydration
• The iris stops producing aqueous humor
• Bowman layer becomes vascularized immediately
• The corneal epithelium begins producing vitreous humor

Q3. Why can a superficial corneal epithelial abrasion heal relatively quickly?

• The epithelium can regenerate through cell migration and proliferation
• Bowman layer rapidly regenerates after every injury
• Endothelial cells form a new epithelium
• Stromal collagen is replaced within minutes

Q4. Why can injury extending into Bowman layer or the anterior stroma produce lasting optical effects?

• The optic nerve replaces damaged collagen
• Deeper healing can produce scar tissue that disrupts transparency
• The retina migrates into the injured cornea
• The lens permanently enters the corneal defect

Q5. Why can the cornea often be transplanted without direct vascular anastomosis?

• The optic nerve supplies nutrients directly to the graft
• The cornea has a large central artery that reconnects spontaneously
• The cornea is normally avascular and receives nutrients largely by diffusion
• The graft receives nutrition only from the vitreous body

Q6. How does the cornea contribute more refractive power than the lens under normal conditions?

• The cornea contains photoreceptors that bend light
• The cornea changes shape during accommodation more than the lens
• The cornea focuses light by active muscular contraction
• The air-cornea interface creates a large refractive-index change

Q7. Why can prolonged contact lens wear with inadequate oxygen transmission affect corneal physiology?

• It blocks the central retinal artery
• It can reduce atmospheric oxygen diffusion to the avascular cornea
• It prevents aqueous humor formation
• It paralyzes the ciliary muscle

Q8. Why does damage to the ophthalmic division of the trigeminal nerve increase risk of corneal injury?

• CN V1 normally produces aqueous humor
• CN V1 directly controls the lens shape
• Loss of corneal sensation reduces protective detection and reflex responses
• CN V1 supplies retinal photoreceptors

Q9. Which anatomical relationship is most important when considering the cornea as the anterior wall of the anterior chamber?

• Its posterior surface faces aqueous humor and its periphery contributes to the iridocorneal angle
• Its posterior surface is attached directly to the retina
• Its anterior surface directly contacts the lens
• Its center contains the scleral venous sinus

Q10. Which statement best integrates corneal structure and function?

• It is a posterior ocular membrane that produces vitreous humor
• Its layered, avascular architecture combines protection, transparency, sensation, and refraction
• It is a vascular neural layer specialized for phototransduction
• It is a smooth muscle structure that controls pupil diameter