Differential Diagnosis for Right Corner Eye Pain and Redness

• Single most likely diagnosis
  • Dry eye syndrome: This condition is a common cause of eye pain and redness, especially in the corners of the eyes, without any discharge or known abrasion cause. It occurs due to insufficient lubrication of the eyes.
• Other Likely diagnoses
  • Blepharitis: Inflammation of the eyelids can cause pain and redness, particularly at the corners of the eyes. It's often associated with a gritty sensation and can be caused by bacterial or demodex mite infestations.
  • Conjunctivitis (viral or allergic): Although the question mentions no discharge, mild cases can present with minimal or no discharge. Viral conjunctivitis often starts in one eye and can cause significant discomfort and redness.
  • Trichiasis or entropion: Misdirected eyelashes or an inward-turning eyelid can cause chronic irritation and pain, especially if the lashes rub against the cornea.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Acute angle-closure glaucoma: This is an ocular emergency that can present with severe eye pain, redness, and vision changes. Although it typically involves more than just the corner of the eye, it's crucial to consider due to its potential for permanent vision loss.
  • Scleritis or episcleritis: Inflammation of the sclera or episclera can cause severe pain, redness, and tenderness to the touch. These conditions can be associated with systemic diseases and require prompt treatment.
• Rare diagnoses
  • Phlyctenular keratoconjunctivitis: An allergic type of conjunctivitis that can cause nodules on the conjunctiva or cornea, leading to pain and redness, often in children.
  • Foreign body sensation without a visible foreign body: Sometimes, a small foreign body can lodge in the eye and not be visible, causing chronic irritation and pain, especially if it's located under the eyelid.