Iris bombe occurs is:
**Core Concept**
Iris bombe is a complication that occurs due to the accumulation of aqueous humor in the posterior chamber of the eye, leading to a bulging of the iris. This condition is often associated with angle-closure glaucoma, where the iris is pushed forward, blocking the drainage of aqueous humor.
**Why the Correct Answer is Right**
Iris bombe occurs due to the obstruction of the trabecular meshwork, which is the primary site of aqueous humor drainage in the eye. When the trabecular meshwork is blocked, the aqueous humor accumulates in the posterior chamber, causing the iris to bulge forward. This is often seen in conditions such as neovascular glaucoma, uveitis, or after cataract surgery.
**Why Each Wrong Option is Incorrect**
**Option A:** Iris bombe is not typically associated with open-angle glaucoma, as the trabecular meshwork is not obstructed in this condition.
**Option B:** Iris bombe is not a direct result of cataract formation, although it can occur as a complication of cataract surgery.
**Option C:** Iris bombe is not a characteristic feature of conjunctivitis, which is an inflammation of the conjunctiva.
**Clinical Pearl / High-Yield Fact**
Iris bombe is a sign of increased intraocular pressure, which can lead to optic nerve damage and vision loss if left untreated. It is essential to diagnose and manage angle-closure glaucoma promptly to prevent long-term vision loss.
**Correct Answer: D.**