acute angle-closure glaucoma

Introduction

An uncommon form of glaucoma considered an ocular emergency.

Etiology

• iridocorneal angle crowding
• pupillary block
• neovascularization
• inflammation of a membrane closing the iridocorneal angle
• mechanical closure of the iridocorneal angle secondary to anterior displacement of the lens-iris diaphragm
  • cataracts
• precipitating factors
  • labor of pregnancy (rare)
  • sneezing
  • ocular laser therapy
  • ocular surgery
  • ocular injury
  • pharmacologic agents
    • mydriatics
    • sympathomimetics
    • antihistamines
      • chlorpheniramine with highest risk
    • neurologic agents & psychotropic agents
      • sumatriptan, topiramate, & duloxetine with highest risk
    • acetylcysteine with high risk
    • others: (lower risk)
      • amitriptyline, escitalopram, nortriptyline
      • alprazolam, diazepam, buspirone
      • aminophylline, pseudoephedrine
      • lactulose, metoclopramide, dimenhydrinate
      • solifenacin
      • naproxen, ibuprofen, orphenadrine
      • levofloxacin, ofloxacin, clarithromycin
      • prednisolone, methylprednisolone
      • ammonium chloride
    • table of 61 drugs
• risk factors
  • hyperopia: smaller eyes with narrower angles

Epidemiology

• more common with hyperopia (far-sightedness)
• more common in women
• more common in Alaskan natives

Pathology

• blockage of the anterior chamber angle structure by the peripheral iris, thus preventing aqueous humor outflow
• the iris may come into contact with the lens & block outflow of aqueous humor
• elevated intraocular pressure
  • blurry vision & hazy cornea
  • damage to the optic nerve

Clinical manifestations

• acute onset
• severe eye pain
• blurred vision (may be triggered by low light)
• injected conjunctiva (erythema)
• complaints of colored halos around lights
• nausea/vomiting
• frontal headache
• red eye, conjunctival hyperemia
• semidilated pupil(s), minimally reactive to light or unreactive to light
• increased intraocular pressure, 55 mm Hg (case report)
• corneal edema, hazy cornea
• shallow anterior chamber
• closed iridocorneal angle in the involved eye
• blindness within a few hours to days if not diagnosed & treated immediately
• eye may feel firm & tender to palpation
• no erythema or edema of eyelids or surrounding eye structures

* image

Diagnostic procedures

• ophthalmoscopy
  • may be normal
  • optic disk cupping if chronic
  • hazy cornea without fluorescein staining

Differential diagnosis

• orbital cellulitis
  • erythema &/or edema of eyelids & surrounding structures
  • no frontal headache
  • no halos around lights
• uveitis: red eye, photophobia
• scleritis:
  • painful red eye, photophobia, edema of sclera
  • dilation of episcleral blood vessels
• corneal abrasion: red eye,clear cornea, eye foreign body sensation
• corneal ulcer: eye foreign body sensation, red eye, corneal opacity
• giant cell arteritis: no eye pain
• bacterial keratitis:
  • contact lenses users
  • eye pain, redness, foreign body sensation
  • no halos around lights, nausea/vomiting, or periorbital headache

Management

• rapidly relieve increased intraocular pressure
• referral to ophthalmology
  • pilocarpine 2%, 2 drops in affected eye
  • send to ophthalmology
• laser therapy - peripheral iridectomy
• surgery: iridotomy within hour of symptom onset
• pharmacologic agents
  • miotics
  • mannitol
• 50% incidence of acute angle-closure in the other eye within 5 years, thus long-term treatment is indicated

More general terms

• secondary glaucoma

More specific terms

• plateau iris syndrome

Additional terms

• glaucomatocyclitic crisis (Posner-Schlossman Syndrome)
• increased intraocular pressure (IOP)