> Table of Contents > Glaucoma, Primary Closed-Angle
Glaucoma, Primary Closed-Angle
H. Anh Hinshaw, MD
David S. Pfoff, MD
image BASICS
DESCRIPTION
  • Primary angle closure suspect (PACS): eye has narrow or occludable anterior chamber angle, but no other abnormalities (1)
  • Primary angle closure (PAC): signs of trabecular meshwork obstruction appear, such as increased intraocular pressure (IOP) or synechiae formation (1)
    • Acute angle closure: sudden block of meshwork by iris (2)
    • Subacute (intermittent) angle closure: periodic acute episodes with normal IOP between (2)
    • Chronic angle closure: most common, refers to an eye with permanent closure of areas of the anterior chamber angle by peripheral anterior synechiae (1)[C]
  • Primary angle closure glaucoma (PACG): glaucomatous optic neuropathy and visual field loss are present (1)[C].
Geriatric Considerations
Increased risk with age and prior history of cataract, hyperopia, and/or uveitis
Pregnancy Considerations
Medications used may cross the placenta and be excreted into breast milk.
EPIDEMIOLOGY
  • Age >40 years
  • Female > male
  • Inuit and Asian > African and European
Prevalence
  • Estimated that over 23 million (in 2020) and 32 million (in 2040) people worldwide will have PACG with the majority in Asia (3)
  • PACG is not as common in the United States, accounts for 10% of all glaucoma (2).
ETIOLOGY AND PATHOPHYSIOLOGY
  • Iridotrabecular contact (ITC): instigating factor; peripheral iris apposition to the posterior trabecular meshwork (1)
  • ITC causes obstruction of aqueous humor outflow through the trabecular meshwork, which causes elevation in IOP. Prolonged ITC can cause scarring to form, degradation of trabecular meshwork, and loss of vision (1).
  • Most common underlying mechanism of PAC is anterior lens displacement, leading to pupillary block in which aqueous humor egress through the pupil is limited. This causes pressure to build posterior in the peripheral iris, leading to anterior bowing of the iris and closing of the angle (1,2).
  • Other mechanisms include predisposing ocular anatomy, such as plateau iris (2)
Genetics
First-degree relatives have a 1-12% increased risk in whites, 6 times greater risk in Chinese patients with positive family history.
RISK FACTORS
  • Hyperopia
  • Age >40 years
  • Shallow anterior chamber
  • Female gender
  • Family history of angle closure
  • Asian or Inuit descent
  • Short axial length
  • Thick crystalline lens
  • Anterior positioned lens
  • Plateau iris
  • Drugs that can induce angle-closure:
    • Adrenergic agonists (albuterol, phenylephrine), anticholinergics (oxybutynin, atropine, botulinum toxin A), antihistamines, antidepressants including selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs), cholinergic agents, sulfa-based drugs, topiramate, cocaine, ecstasy (4)[A]
GENERAL PREVENTION
  • Routine eye exam with gonioscopy for high-risk populations
  • U.S. Preventive Services Task Force: insufficient evidence to recommend for or against screening adults for open-angle glaucoma (5)[A]
  • Prophylactic laser iridotomy for PACS patients has been found to be effective in preventing PACG.
  • Prophylactic laser iridotomy in contralateral eye of patients that have had unilateral acute PAC has been effective in preventing acute attacks in the contralateral eye (2)[C].
COMMONLY ASSOCIATED CONDITIONS
  • Cataract
  • Hyperopia
  • Microphthalmos
  • Systemic hypertension
image DIAGNOSIS
PHYSICAL EXAM
  • Includes, but is not limited to, the following in the undilated eye (1)[C]
    • Visual acuity
    • Visual field testing and ocular motility
    • Pupil size and reactivity (mid-dilated, minimally reactive)
    • External examination
    • Undilated fundus exam (congestion, cupping, atrophy of optic nerve)
    • Slit-lamp exam (anterior segments)
    • Tonometry (determination of IOP)
    • Gonioscopy (visualization of the angle)
  • Acute (6)[C]
    • Elevated IOP (>21 mm Hg)
    • Corneal microcystic edema (haze)
    • Hyperemic conjunctiva
    • Mid-dilated, nonreactive, or irregular pupil
    • Shallow anterior chamber, often with inflammatory reaction (cell and flare in anterior chamber)
    • Pain with eye movement
    • Closed angle by gonioscopy or anterior segment optical coherence tomography (AS-OCT)
  • Chronic (6)[C]
    • Multiple peripheral anterior synechiae
    • Normal or elevated IOP
    • Increased cup-to-disc ratio or excavation of disc
    • Glaucoma flecks (lens) and iris atrophy (previous acute attacks)
DIFFERENTIAL DIAGNOSIS
  • Acute orbital compartment syndrome
  • Traumatic hyphema
  • Conjunctivitis, episcleritis
  • Corneal abrasion
  • Glaucoma, malignant or neovascular
  • Herpes zoster ophthalmicus
  • Iritis and uveitis
  • Orbital/periorbital infection
  • Vitreous or subconjunctival hemorrhage
  • Tight necktie, causing increased IOP
  • Lens-induced angle closure
DIAGNOSTIC TESTS & INTERPRETATION
Initial Tests (lab, imaging)
Ultrasound (US) biomicroscopy AS-OCT (1)[C]
Diagnostic Procedures/Other
Careful ophthalmic examination, including gonioscopy and tonometry (1)[C]
Test Interpretation
  • Narrow or closed anterior angle
  • Corneal stromal and epithelial edema
  • Endothelial cell loss (guttata)
  • Iris stromal necrosis
  • Anterior subcapsular cataract (glaukomflecken)
  • Optic disc congestion, cupping, excavation
  • Optic nerve atrophy
image TREATMENT
Goals of treatment (1)[C]:
  • Reverse or prevent angle-closure process
  • Control IOP
  • Prevent damage to the optic nerve
GENERAL MEASURES
  • For acute attack: ocular emergency
    • Manage nausea and pain
    • Immediate ophthalmology consultation
    • Goals of therapy through medical and surgical treatment: reduce IOP to <35 mm Hg or by >25% of presenting IOP (7)[B]
MEDICATION
  • During acute attack, therapy can be initiated with 2% pilocarpine, 0.5% timolol maleate, and 1% apraclonidine drops 1 minute apart, and acetazolamide 500 mg PO, glycerin (Osmoglen) (50%) 6 oz PO, and IV mannitol 20% 1.5 to 2g/kg infused over 30 to 60 minutes for a rapid decrease in IOP; after the cornea clears, a peripheral iridotomy is done (8)[C].
  • P.411

  • Additionally, medical therapy to decrease IOP and clear the cornea prior to surgery can also be accomplished using some or all of the following (1,9)[C]:
    • Carbonic anhydrase inhibitors (CAIs):
      • Contraindications/precautions: sulfa allergy, hepatic insufficiency
      • Systemic:
        • Acetazolamide (Diamox): 500 mg IV/PO; may repeat with 250 mg in 4 hours to a maximum of 1 g/day
        • Methazolamide (Neptazane): 50 to 100 mg PO BID-TID
      • Topical:
        • Dorzolamide (Trusopt) 2% eyedrops: 1 drop in affected eye(s) TID
        • Brinzolamide (Azopt) 1% suspension: 1 drop in affected eye(s) TID
    • &bgr;-Blockers:
      • Contraindications/precautions: decompensated heart failure, sinus bradycardia, heart block, severe COPD/asthma
        • Timolol (Timoptic) 0.25-0.5% solution: 1 drop in affected eye(s) BID
        • Timolol (Timolol GFS, Timoptic-XE) 0.25-0.5% gel-forming solution: 1 drop daily
        • Levobunolol (Betagan) 0.5% solution: 1 drop in affected eye(s) 1 to 2 times daily
        • Betaxolol (Betoptic) 0.5% solution: 1 to 2 drops in affected eye(s) BID
        • Carteolol (Ocupress)1% solution: 1 drop in affected eye(s) BID
        • Metipranolol (Optipranolol) 0.3% solution: 1 drop in affected eye(s) BID
    • &agr;2-Agonists: (used as adjunct therapy)
      • Contraindications/precautions: MAO inhibitor therapy
        • Brimonidine (Alphagan P) 0.15%, 0.2% solution: 1 drop in affected eye(s) TID
        • Apraclonidine (Iopidine) 0.5% solution: 1 to 2 drops in affected eye(s) TID
    • Prostaglandin analogs:
      • Precautions: changes to iris, eyelid, and eyelash pigmentation, eyelash growth, irritation, redness; can cause corneal epithelium herpes to recur
        • Latanoprost (Xalatan) 0.005% solution: 1 drop in affected eye(s) daily
        • Travoprost (Travatan Z) 0.004% solution: 1 drop in affected eye(s) daily
        • Bimatoprost (Lumigan) 0.01% solution: 1 drop in affected eye(s) daily
        • Tafluprost (Zioptan) 0.0015% solution: 1 drop in affected eye(s) nightly
        • Unoprostone (Rescula) 0.15% solution: 1 drop in affected eye(s) BID
    • Direct cholinergic agonists:
      • Precautions: may worsen the condition due to anterior rotation of the lens-iris diaphragm, impaired night vision, color vision changes
        • Pilocarpine (Isopto Carpine) (1%, 2%, 4% solution): 1 drop up to 6 times daily to reduce IOP; for acute attack, 1 drop of 1-2% in affected eye(s) every 10 minutes up to 3 doses
    • Cholinesterase inhibitor:
      • Precautions: may worsen the condition due to anterior rotation of the lens-iris diaphragm, impaired night vision
        • Echothiophate iodide (Phospholine Iodide) 0.125% solution: 1 drop BID
      • Combination products:
        • Timolol-Dorzolamide (Cosopt) 0.5%/2% solution: 1 drop in affected eye(s) BID
        • Timolol-Brimonidine (Combigan) 0.5%/0.2% solution: 1 drop in affected eye(s) BID
        • Brinzolamide-Brimonidine (Simbrinza) 1%/0.2% solution: 1 drop in affected eye(s) TID
ADDITIONAL THERAPIES
Keep patient supine.
SURGERY/OTHER PROCEDURES
  • Acute (1)[C],(6)[B]
    • Laser peripheral iridotomy is preferred surgical treatment, but surgical iridectomy can be used if laser is not available.
  • Subacute and chronic (1,5,10)[B]
    • Laser iridectomy for pupillary block
    • Goniosynechialysis to separate synechiae
    • Phacoemulsification to remove cataract
INPATIENT CONSIDERATIONS
Admission Criteria/Initial Stabilization
  • Patient requires metabolic ± electrolyte and volume status monitoring (with osmotic agents).
  • Facilitate close ophthalmology monitoring.
image ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
Schedule an immediate ophthalmologic follow-up.
Patient Monitoring
  • Postsurgical follow-up
  • Evaluation of the contralateral eye
  • Routine monitoring after acute attack per ophthalmologist recommendations
PATIENT EDUCATION
  • Advise patient to seek emergency medical attention if experiencing a change in visual acuity, blurred vision, eye pain, or headache.
  • If narrow angles, but no peripheral iridotomy performed: Avoid decongestants, motion sickness medications, adrenergic agents, antipsychotics, antidepressants, and anticholinergic agents.
  • Correct eyedrop administration technique, including the following:
    • Remove contact lenses before administration and wait 15 minutes before reinserting.
    • Allow at least 5 minutes between administration of multiple ophthalmic products.
  • Patients with significant visual impairment should be referred to vision rehab and social services.
  • Patient education materials:
    • Glaucoma Research Foundation: http://www.glaucoma.org
    • National Eye Institute: http://www.nei.nih.gov
PROGNOSIS
  • With timely treatment, most patients do not have permanent vision loss.
  • Prognosis depends on ethnicity, underlying eye disease, and time-to-treatment.
REFERENCES
1. American Academy of Ophthalmology. Primary Angle Closure Preferred Practice Pattern. San Francisco, CA: American Academy of Ophthalmology; 2010. http://www.aao.org.
2. Patel K, Patel S. Angle-closure glaucoma. Dis Mon. 2014;60(6):254-262.
3. Tham YC, Li X, Wong TY, et al. Global prevalence of glaucoma and projections of glaucoma burden through 2040: a systematic review and meta-analysis. Ophthalmology. 2014;121(11): 2081-2090.
4. Subak-Sharpe I, Low S, Nolan W, et al. Pharmacological and environmental factors in primary angle-closure glaucoma. Br Med Bull. 2010;93: 125-143.
5. Moyer VA. Screening for glaucoma: U.S. Preventive Services Task Force Recommendation Statement. Ann Intern Med. 2013;159(7): 484-489.
6. Saw SM, Gazzard G, Friedman DS. Interventions for angle-closure glaucoma: an evidence-based update. Ophthalmology. 2003;110(10): 1869-1878.
7. Choong YF, Irfan S, Menage MJ. Acute angle closure glaucoma: an evaluation of a protocol for acute treatment. Eye (Lond). 1999;13(Pt 5): 613-616.
8. Pokhrel PK, Loftus SA. Ocular emergencies. Am Fam Physician. 2007;76(6):829-836.
9. Kolko M. Present and new treatment strategies in the management of glaucoma. Open Ophthalmol J. 2015;9:89-100.
10. Qing G, Wang N, Mu D. Efficacy of goniosynechialysis for advanced chronic angle-closure glaucoma. Clin Ophthalmol. 2012;6:1723-1729.
See Also
&NA;
Glaucoma, Primary Open-Angle
Codes
&NA;
ICD10
  • H40.20X0 Unsp primary angle-closure glaucoma, stage unspecified
  • H40.219 Acute angle-closure glaucoma, unspecified eye
  • H40.2290 Chronic angle-closure glaucoma, unsp eye, stage unspecified
Clinical Pearls
&NA;
  • Examiner can determine if patient is hyperopic by observing the magnification of the patient's face through his or her glasses (myopic lenses minify).
  • A careful history may reveal similar episodes of angle closure that resolved spontaneously.
  • Miotics, such as pilocarpine, can be effective during mild attacks, but in the setting of high IOP (due to iris sphincter ischemia), other agents such as CAIs, prostaglandin analogs, &agr;2-agonists, and &bgr;-blockers are necessary.