What is the initial approach to a patient presenting with eye pain?

Initial Approach to Eye Pain

The initial approach to a patient with eye pain should include a thorough ocular surface and tear parameter examination to evaluate for nociceptive sources of pain, including aqueous tear deficiency, tear film instability, inflammation, and epithelial erosions. 1

Diagnostic Evaluation

History Taking

• Assess the duration, character, and severity of pain (burning, stinging, aching) 1
• Determine if symptoms are unilateral or bilateral 1
• Evaluate for associated symptoms such as photophobia, wind hyperalgesia, or sensitivity to light 1
• Document recent history of ocular surgeries, infections, trauma, or chronic ocular surface abnormalities 1
• Inquire about systemic conditions that may contribute to eye pain (migraine, fibromyalgia) 1
• Assess for red flag symptoms such as worsening visual acuity, severe pain, or light sensitivity that may indicate urgent conditions 1

Physical Examination

• Measure visual acuity as a baseline assessment 1
• Perform external examination for regional lymphadenopathy, particularly preauricular nodes 1
• Conduct slit-lamp biomicroscopy to evaluate the conjunctiva, eyelids, sclera, cornea, pupil, anterior chamber, and anterior uvea 1
• Assess for signs of ocular surface disorders such as:
  • Conjunctival injection or follicles 1
  • Corneal epithelial defects or erosions 1
  • Tear film abnormalities 1
  • Signs of inflammation 1

Diagnostic Tests

First-Line Tests

• Fluorescein staining to evaluate corneal epithelial integrity and tear break-up time 1
  • Apply fluorescein strip moistened with sterile nonpreserved saline to the inferior tarsal conjunctiva 1
  • Examine with cobalt blue filter to assess for epithelial defects and tear film stability 1
• Anesthetic challenge test for suspected neuropathic ocular pain 1
  • If pain improves after anesthetic drop instillation, this suggests a nociceptive or peripheral neuropathic component 1
  • If pain persists, this suggests a central or nonocular cause 1

Additional Tests Based on Initial Findings

• Tonometry to measure intraocular pressure if glaucoma is suspected 1
• Pupillary assessment to rule out neurological causes 2
• Ocular surface questionnaires such as Neuropathic Pain Symptom Inventory (NPSI)-Eye or Ocular Pain Assessment Survey (OPAS) for suspected neuropathic pain 1

Differential Diagnosis and Management Approach

Urgent Conditions Requiring Immediate Referral

• Acute angle-closure glaucoma: Presents with severe eye pain, headache, nausea/vomiting, decreased vision, and elevated intraocular pressure 1, 3
• Optic neuritis: Presents with eye pain that worsens with eye movement, decreased vision, and possible afferent pupillary defect 2, 3
• Retinal or ophthalmic artery occlusion: Requires urgent referral to a stroke center within 24 hours due to high risk of concurrent cerebrovascular accident 1
• Orbital cellulitis: Presents with eye pain, proptosis, limited eye movement, and eyelid swelling 3

Common Non-Urgent Causes

• Dry eye syndrome: Manage with ocular lubricants and treatment of underlying inflammation 1
• Conjunctivitis: Treatment depends on etiology (viral, bacterial, allergic) 1
• Corneal abrasion: Treat with topical antibiotics and pain management 3
• Neuropathic ocular pain: Consider topical nerve regenerative therapies for peripheral pain or oral neuromodulators for central pain 1

Management Algorithm

1. Assess for red flags requiring emergency referral:

   • Severe pain with decreased vision 1, 3
   • Pain with eye redness and elevated intraocular pressure 1
   • Pain with proptosis or limited eye movement 3
   • Pain with sudden vision loss 1

2. If no red flags, proceed with basic evaluation:

   • Fluorescein staining to assess corneal integrity 1
   • Tear film evaluation 1
   • Assessment of conjunctiva and eyelids 1

3. For suspected neuropathic pain:

   • Perform anesthetic challenge test 1
   • Consider questionnaires to assess neuropathic qualities 1
   • Evaluate for symptoms that outweigh clinical signs 1

4. For persistent pain without clear etiology:

   • Consider neuroimaging to rule out orbital or neurological causes 4
   • Evaluate for referred pain from other structures 5
   • Consider consultation with neurology if migraine is suspected 6

Common Pitfalls and Caveats

• Neuropathic ocular pain is often misdiagnosed as symptoms may outweigh clinical signs 1
• Unilateral eye symptoms are very unlikely to be related to systemic conditions and should prompt evaluation for local pathology 1, 5
• Eye pain may be the first sign of an ophthalmologic emergency, so thorough evaluation is essential 3
• Patients with eye pain may present to either neurology or ophthalmology clinics, and management often requires collaboration between specialties 6
• Avoid using fluorescein-anesthetic combination drops for tear break-up time assessment as the anesthetic may affect test results 1