This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Ophthalmology
All are ophthalmological emergencies except ? 
Select and explain. 
A. CRAO, B. CRVO, C. Acute congestive glaucoma, D. Endophthalmitis
B: CRVO
Answer: B: CRVO 
Explanation: Ans. is 'b' i.e., CRVO Ocular emergencies include those conditions that result in acute, severe pain in association with sudden vision loss, or that may lead to vision loss if left untreated; and traumatic conditions that affect globe or adnexa. Comon ophthalmic emergencies are :- Acute congestive glaucoma Ulcerative or traumatic corneal diseases Hyphema Acute blindness Eyelid or conjunctival laceration Anterior lens subluxation Ruptured globe Optic neuritis Endophthalmitis Orbital cellulitis Central retinal aerial occlusion (CRAG) Retinal detachment