How does anterior lens luxation cause glaucoma?

• A. The lens moves forward with the vitreous, acting like a cork in the iridocorneal angle
• B. Increased aqueous production
• C. Rupture of the lens capsule
• D. Iris pressure

Answer: (C)

When the lens sits abnormally in the front of the eye, it can physically block the normal outflow of aqueous humor. The displaced lens often pushes the iris forward and sits against the pupil or fills the iridocorneal angle, creating a pupillary block and narrowing or closing the drainage angle. With the angle blocked, aqueous humor cannot reach the trabecular meshwork, so intraocular pressure rises rapidly, producing acute glaucoma.

The other ideas don’t fit the usual mechanism. Glaucoma here isn’t driven by more aqueous production, and rupture of the lens capsule isn’t the primary cause of the pressure spike (it can lead to inflammation or different complications, but not the immediate outflow obstruction caused by the lens occupying the anterior chamber). Iris pressure alone doesn’t explain how blockage of outflow leads to elevated IOP.