Immediate Ophthalmology Referral for Acute Angle-Closure Glaucoma
This patient requires urgent same-day ophthalmology evaluation for suspected acute angle-closure glaucoma (AACG), as the combination of eye pain, decreased vision, and known glaucoma history not on treatment represents a vision-threatening emergency that can cause irreversible blindness within hours to days. 1
Critical Clinical Context
This presentation is highly concerning for acute angle-closure crisis, even without the classic signs of redness or corneal edema:
- Pain with decreased vision in a glaucoma patient off medication for 1 week is an ophthalmologic emergency 1
- AACG can present with variable symptoms; not all patients exhibit conjunctival hyperemia or corneal edema, particularly in subacute or intermittent cases 1
- Untreated AACG causes rapid glaucomatous optic neuropathy with axonal swelling within days, progressing to permanent axonal atrophy by 3 months 1
- 18% of eyes become blind following AACG, with 50% of blindness attributable to glaucoma itself 1
Immediate Actions Required
Urgent Referral Protocol
- Send immediately to emergency ophthalmology or nearest stroke-ready hospital with ophthalmology services 1
- Time is critical: retinal nerve fiber layer damage begins within the first few days of elevated intraocular pressure 1
- Do not delay for imaging or additional testing in primary care 1
Key Diagnostic Features to Communicate
The ophthalmologist will need to assess:
- Intraocular pressure measurement (tonometry) - may be markedly elevated (>40-50 mmHg) in AACG 1
- Gonioscopy - to evaluate anterior chamber angle closure with iridotrabecular contact 1
- Pupil examination - may show mid-dilated, poorly reactive, or oval pupil in affected eye 1
- Slit-lamp examination - assess for shallow anterior chamber, corneal edema, and conjunctival injection 1
- Optic nerve assessment - evaluate for glaucomatous cupping and nerve fiber layer damage 1
Differential Considerations
While AACG is the primary concern, the ophthalmologist must also evaluate for:
- Primary open-angle glaucoma progression - uncontrolled IOP from medication discontinuation can cause subacute symptoms 1
- Intermittent angle closure - patients may experience episodes of blurred vision, halos, and pain that resolve spontaneously 1
- Secondary glaucoma - from other ocular conditions 1
The absence of redness does not exclude angle-closure disease, as subacute or chronic presentations may lack prominent conjunctival hyperemia 1
Risk Factors Present
This patient has multiple high-risk features:
- Known glaucoma history - fellow eye at increased risk for acute angle closure (88-89% risk in untreated phakic eyes) 1
- Currently off medication - uncontrolled IOP accelerates optic nerve damage 1
- One week symptom duration - sufficient time for significant irreversible damage 1
Expected Ophthalmologic Management
Once evaluated, treatment typically includes:
- Immediate IOP reduction with topical beta-blockers (timolol), alpha-agonists (apraclonidine), and topical/systemic carbonic anhydrase inhibitors (acetazolamide 250-500mg) 2, 3
- Laser peripheral iridotomy - definitive treatment to prevent recurrent angle closure 1
- Prophylactic treatment of fellow eye - to prevent bilateral blindness 1
- Consideration of lens extraction if angle remains closed or in chronic cases 1
Critical Pitfalls to Avoid
- Do not assume absence of redness excludes serious pathology - subacute angle closure can present with minimal external signs 1
- Do not delay referral for "observation" - every hour of untreated elevated IOP increases risk of permanent vision loss 1
- Do not restart previous glaucoma medications without ophthalmology evaluation - acute angle closure requires different management than chronic open-angle glaucoma 1
- Do not use anticholinergic or adrenergic medications that could precipitate further angle closure 1
Prognosis Without Treatment
The natural history of untreated AACG is severe: