What are the potential causes and treatments for sudden onset right eye pain with a pressure sensation?

Differential Diagnosis for Acute Right Eye Pain with Pressure Sensation

Acute angle-closure glaucoma is the most critical diagnosis to rule out immediately, as this represents an ophthalmic emergency that can cause irreversible blindness within hours if untreated. 1, 2

Immediate Life/Sight-Threatening Causes

Acute Angle-Closure Crisis (AACC)

• Classic presentation: Sudden onset severe eye pain with pressure sensation, blurred vision, halos around lights, mid-dilated fixed pupil, corneal edema, markedly elevated intraocular pressure (IOP often >40 mmHg), and potentially nausea/vomiting 3, 2
• Risk factors to assess: Hyperopia, age >50, female gender, Asian ethnicity, shallow anterior chamber, family history of angle-closure 2
• Critical examination: Measure IOP immediately, assess pupil reactivity, check for corneal edema with slit lamp, and perform gonioscopy to visualize angle closure 1, 2
• Urgent action required: If IOP is elevated with narrow/closed angles, initiate immediate medical therapy with topical beta-blockers, alpha-2 agonists, carbonic anhydrase inhibitors, and oral/IV hyperosmotic agents, followed by emergent laser peripheral iridotomy (LPI) once IOP controlled 3, 2

Intermittent Angle Closure (Subacute)

• Presentation: Transient episodes of eye pain/pressure with blurred vision and halos that resolve spontaneously, often bilateral 1
• Warning sign: These represent prodromal episodes before acute crisis—untreated fellow eyes have ~50% risk of acute attack within 5 years 1
• Management: Requires urgent (not emergent) ophthalmology referral for gonioscopy and prophylactic LPI in both eyes 1

Retinal/Ophthalmic Artery Occlusion

• Presentation: Sudden painless vision loss is typical, but eye pain can occur with associated ischemia 3
• Critical action: If vision loss present, refer immediately to stroke center—20-24% have concurrent cerebral infarction, and stroke risk is highest in first 7 days 3

Other Important Causes

Corneal Pathology

• Corneal abrasion/ulcer: Sharp pain, foreign body sensation, photophobia, visible epithelial defect on fluorescein staining
• Keratitis: Pain, redness, discharge, decreased vision

Anterior Uveitis/Iritis

• Presentation: Dull aching pain, photophobia, circumlimbal injection, cells/flare in anterior chamber
• Differentiation from AACC: Pupil typically small (not mid-dilated), IOP normal or low (not elevated)

Scleritis/Episcleritis

• Scleritis: Deep boring pain worse at night, violaceous hue, may radiate to face
• Episcleritis: Milder discomfort, sectoral redness, benign course

Optic Neuritis

• Presentation: Pain with eye movement, decreased vision, relative afferent pupillary defect, normal anterior segment

Referred Pain

• Sinusitis: Periorbital pressure, worse with bending forward, nasal congestion
• Migraine: Unilateral headache, photophobia, may have visual aura
• Trigeminal neuralgia: Sharp lancinating pain in V1 distribution

Critical Decision Algorithm

Step 1: Measure IOP and assess pupil

• If IOP >21 mmHg with mid-dilated pupil → Assume AACC until proven otherwise, initiate emergency treatment 3, 2

Step 2: Assess vision and cornea

• If sudden vision loss → Consider retinal artery occlusion, refer to stroke center 3
• If corneal edema with high IOP → AACC 2
• If corneal defect with normal IOP → Corneal pathology

Step 3: Examine anterior chamber

• If shallow chamber with narrow angles → High risk for angle closure, urgent ophthalmology referral 1
• If cells/flare present → Anterior uveitis

Step 4: Check for red flags

• Pain with eye movement + vision loss → Optic neuritis
• Deep violaceous injection → Scleritis
• History of transient episodes with halos → Intermittent angle closure requiring urgent prophylactic treatment 1

Critical Pitfalls to Avoid

• Never dilate the pupil in a patient with suspected narrow angles or intermittent angle closure symptoms until after LPI is performed—dilation can precipitate acute crisis 1
• Do not dismiss transient symptoms as benign; intermittent episodes are warning signs before potentially blinding acute attacks 1
• Do not delay treatment waiting for ophthalmology consultation if AACC suspected—18% of untreated eyes become blind within 4-10 years 3, 2
• Remember the fellow eye: After treating one eye with angle closure, the fellow eye requires prophylactic treatment as acute attacks can occur within days 1