Posterior lenticonus is best described as an outpouching of which structure?

• A. Posterior lens capsule
• B. Anterior lens capsule
• C. Vitreous face
• D. Retinal pigment epithelium

Answer: (A)

Posterior lenticonus is a congenital bulge of the back surface of the lens, where the posterior lens capsule protrudes into the vitreous as a cone-shaped outpouching. This means the structure involved is the posterior lens capsule—the outpouching originates from the lens’s posterior boundary. The other structures listed aren’t the site of this outpouching: the anterior lens capsule is the front surface of the lens, the vitreous face is the boundary of the vitreous body, and the retinal pigment epithelium is part of the retina.