A patient presents with sudden onset of unilateral eye pain and blurred vision. What should you suspect?

The presentation of sudden onset unilateral eye pain and blurred vision strongly indicates acute angle-closure glaucoma. In this condition, there is a rapid increase in intraocular pressure due to a blockage of the drainage angle of the eye, which can occur suddenly. This blockage leads not only to severe ocular pain and vision changes but may also present with symptoms such as nausea and vomiting. The acute nature of the symptoms and the unilateral presentation are particularly characteristic.

In contrast, spontaneous retinal detachment might lead to similar visual disturbances, but it typically presents with symptoms like flashes of light, floaters, or a shadow over a portion of the visual field, rather than acute pain. Acute optic nerve hypoplasia is a congenital condition typically diagnosed early in life, making it less likely to present in an adult with sudden symptoms. Central retinal arterial occlusion generally manifests with a sudden loss of vision but not necessarily with pronounced pain, making it less likely in this scenario compared to the acute pain seen with angle-closure glaucoma.