**Question:** In Acute angle closure glaucoma all are seen EXCEPT:

A. Increased intraocular pressure (IOP)
B. Acute worsening of vision due to optic nerve damage
C. Conjunctival hyperemia
D. Corneal edema

**Core Concept:** Acute angle closure glaucoma (AACG) is a life-threatening emergency characterized by rapid elevation of intraocular pressure (IOP) due to the closure of the angle between the cornea and the iris, leading to blockade of aqueous humor outflow. This can cause optic nerve damage and visual impairment.

**Why the Correct Answer is Right:** In AACG, the primary issue is the elevated IOP, which directly damages the optic nerve and leads to visual impairment. Corneal edema and conjunctival hyperemia are secondary complications resulting from the elevated pressure, but they are not the primary cause or feature of the disease. Corneal edema is caused by hypoxia due to elevated IOP, while conjunctival hyperemia is a response to inflammation and increased pressure. None of these symptoms is directly related to the primary cause of AACG, which is the angle closure leading to aqueous humor outflow obstruction.

**Why Each Wrong Option is Incorrect:**

A. Corneal edema and conjunctival hyperemia are secondary complications of AACG, not primary features.
B. The primary feature of AACG is optic nerve damage due to elevated IOP, not worsening vision. Although vision may worsen, worsening vision is not a defining feature of AACG in comparison to its primary cause, elevated IOP.
C. Conjunctival hyperemia is a secondary response to inflammation and increased pressure, not a primary feature of AACG.
D. Corneal edema is caused by hypoxia due to elevated IOP, not a primary feature of AACG. Corneal edema is not directly related to the primary cause of AACG, which is the angle closure causing aqueous humor outflow obstruction.

**Clinical Pearl:** In clinical practice, it is essential to promptly recognize and address AACG to prevent irreversible optic nerve damage and visual loss. A sudden onset of severe eye pain, nausea, vomiting, and photophobia are key clinical features that prompt a suspicion of AACG. If left untreated, it can lead to irreversible optic nerve damage and vision loss, emphasizing the importance of early diagnosis and treatment.