Painful Eye

• Eye problems constitute 2% to 3% of all primary care and emergency department visits.
• Common eye conditions causing pain: conjunctivitis, corneal abrasion, hordeolum.
• Serious eye conditions: acute angle-closure glaucoma, orbital cellulitis, herpetic keratitis.
• History should focus on vision changes, foreign body sensation, photophobia, and associated symptoms such as headache.
• Physical examination: visual acuity, conjunctiva, eyelids, sclera, cornea, pupil, anterior chamber, anterior uvea.
• Further examination: fluorescein staining, tonometry.
• Determine if referral to ophthalmology is warranted for emergencies.

History

• Vision loss or changes: Requires immediate ophthalmology referral.
• Foreign body sensation: Suggests corneal process (abrasion, foreign body, keratitis).
• Scratchy, gritty sensation: More likely conjunctivitis.
• Contact lens history: Important for assessing risk of bacterial or Acanthamoeba keratitis.
• Photophobia: Sign of corneal involvement, uveitis, or migraine.
• Headache with eye pain: Possible ophthalmologic/neurologic condition (acute angle-closure glaucoma, scleritis, cluster headaches).
• Systemic disease: Consider in ocular conditions (e.g., scleritis and rheumatologic disease, optic neuritis and multiple sclerosis, recurrent/bilateral uveitis).

Physical Examination

• Equipment: Snellen chart, tonometer, penlight, fluorescein stain, Wood lamp.
• Vision assessment: Snellen chart, kinetic red test, static finger wiggle test.
• Extraocular movement: Pain with movement in conditions like scleritis, optic neuritis, orbital cellulitis, acute angle-closure glaucoma.
• External structures: Inspect for inflammation, erythema, lesions (hordeolum, vesicles in HSV/herpes zoster).
• Conjunctiva: Look for injection, ciliary flush (uveitis, acute angle-closure glaucoma).
• Sclera: Differentiate between scleritis (painful, vision affected) and episcleritis (painless, vision unaffected).
• Cornea: Fluorescein staining for abrasions, herpetic keratitis (dendritic pattern).
• Pupil: Check for anisocoria, photophobia (penlight test), swinging flashlight test (optic neuritis).
• Anterior chamber: Oblique flashlight test for depth, tonometry for intraocular pressure.
• Anterior uvea: Look for hypopyon, use slit lamp for white blood cells/protein flare in anterior chamber.

Anatomic Assessment

External Structures

• Inspection of Eyelids:
  • Look for inflammation, erythema, lesions, or abnormalities.
  • Hordeolum: Tender, inflamed nodule on external or internal eyelid.
  • Upper Lid Eversion: Necessary if corneal abrasion is suspected to check for a foreign body.
  • Orbital Cellulitis: Unilateral erythema, swelling, ptosis, pain with eye movement, decreased visual acuity.
• Inspection for Rashes or Vesicles:
  • HSV Keratitis: Conjunctival or eyelid vesicles.
  • Herpes Zoster Ophthalmicus: Pain and vesicular lesions in a dermatome pattern (forehead, nose, upper eyelid, V1 distribution of the trigeminal nerve).

Conjunctiva

• Structure:
  • Thin mucous membrane covering posterior eyelids (palpebral conjunctiva) and anterior sclera (bulbar conjunctiva).
• Injection Patterns:
  • Diffuse Injection: Disease within conjunctiva itself.
  • Ciliary Flush Sign: Injection radiating outward from the limbus, common in uvea or anterior chamber disease (anterior uveitis, acute angle-closure glaucoma).

Sclera

• Structure:
  • Fibrous, protective coating of the eye, covered anteriorly by the episclera, continuous with the cornea.
• Inflammation:
  • Scleritis: Painful inflammation, can impair vision, bluish discoloration.
  • Episcleritis: Less painful, vision unaffected, sectoral superficial vessel engorgement, blanched with phenylephrine.

Cornea

• Evaluation:
  • Fluorescein staining using a Wood lamp or ophthalmoscope with a cobalt filter.
  • Apply topical anesthetic (e.g., proparacaine 0.5%) if pain precludes evaluation.
• Appearance:
  • Healthy cornea: smooth, shiny, clear.
  • Lesions: yellow in normal light, fluoresce green under cobalt light or Wood lamp.
  • Abrasions: Linear if trauma, round if contact lens use.
  • Herpetic Keratitis: Branching, dendritic appearance.

Pupil

• Normal Size: 2 to 4 mm, constricts with consensual and direct light.
• Anisocoria: Unequal pupil size, less than 1 mm in up to 20% of population.
• Signs of Conditions:
  • Anterior Uveitis: Anisocoria with eye pain.
  • Acute Angle-Closure Glaucoma: Fixed dilated pupil at 4 to 6 mm.
• Photophobia Test: Using penlight to identify discomfort; negative result makes uveitis and keratitis unlikely.
• Swinging Flashlight Test: Diagnose afferent pupillary defect (Marcus Gunn pupil), indicating optic neuritis.

Anterior Chamber

• Structure: Between cornea and iris, filled with aqueous humor.
• Oblique Flashlight Test: Approximate depth of anterior chamber angle; shadow over nasal cornea implies a narrow angle.
• Tonometry: Perform if acute angle-closure glaucoma is suspected; pressures >40-50 mm Hg consistent with diagnosis.

Anterior Uvea

• Structure: Comprises iris and ciliary body.
• Inflammation: Considered anterior uveitis.
• Hypopyon: White blood cells in the anterior chamber, visible without magnification.
• Slit Lamp Examination: Necessary for adequate evaluation.
• Symptoms: Achy eye pain, photophobia, blurred vision.
• Signs: White blood cells floating in the aqueous humor, cloudy proteinaceous flare.

Common Conditions and Management

• Conjunctivitis:
  • Bacterial: Erythema, purulent discharge, treat with broad-spectrum antibiotic drops, culture if severe/contact lens user.
  • Viral: Erythema, serous discharge, supportive care (cold compresses, ocular antihistamines, artificial tears).
• Scleritis:
  • Symptoms: Severe, boring pain, associated with rheumatologic disease.
  • Treatment: NSAIDs (ibuprofen, naproxen, indomethacin), ophthalmology referral.
• Keratitis:
  • Bacterial: Red eye, discharge, photophobia, treat with broad-spectrum antibiotic drops, topical fluoroquinolones/aminoglycosides for contact lens users, ophthalmology referral.
  • Parasitic (Acanthamoeba): Severe pain, photophobia, ring-like infiltrate, treat with NSAIDs, discontinue contact lenses, ophthalmology referral, eye scrapings for culture.
• Corneal Abrasion:
  • Diagnosis: Fluorescein staining, linear if trauma, round if contact lens use.
  • Treatment: Topical NSAIDs, add antibiotics for contact lens users, avoid eye patches.
• Acute Angle-Closure Glaucoma:
  • Symptoms: Elevated intraocular pressure, headache, nausea, vomiting.
  • Treatment: Emergent ophthalmology referral, medications to lower intraocular pressure (topical beta blocker, alpha-2 agonist, systemic carbonic anhydrase inhibitor).
• Anterior Uveitis:
  • Symptoms: Photophobia, ciliary flush, white blood cells in anterior chamber.
  • Treatment: Topical steroids/immunosuppressants, ophthalmology referral, work-up for systemic disease if recurrent/bilateral.
• Orbital Cellulitis:
  • Symptoms: Eyelid swelling, pain with movement, decreased visual acuity.
  • Treatment: IV antibiotics (vancomycin + ceftriaxone/cefotaxime/ampicillin-sulbactam/piperacillin-tazobactam), ophthalmology referral, hospital admission.
• Optic Neuritis:
  • Symptoms: Orbital pain with movement, decreased vision, associated with multiple sclerosis.
  • Treatment: High-dose corticosteroids, neurology and ophthalmology referral, MRI for early diagnosis.

Emergent Ophthalmologic Diseases

• Trauma with hyphema or corneal penetration: Urgent ophthalmology evaluation.
• Acute angle-closure glaucoma: Requires prompt treatment to prevent optic nerve atrophy and vision loss.
• Orbital cellulitis: Needs hospital admission, IV antibiotics, ophthalmology consultation.
• Scleritis: Determine posterior structure involvement, manage vision loss accordingly.
• Anterior uveitis: Requires urgent referral to prevent vision impairment.
• Infectious keratitis: Ophthalmologic referral for bacterial, Acanthamoeba, HSV, and herpes zoster ophthalmicus infections.