Description

• Acute-angle closure (the term glaucoma is added when glaucomatous optic neuropathy is present):
  • At least 2 of the following symptoms: Ocular pain, nausea/vomiting, intermittent blurred vision with halos, plus
  • At least 3 of the following signs: Intraocular pressure (IOP) >21 mm Hg, conjunctival injection, corneal epithelial edema, mid-dilated nonreactive pupil, shallower chamber in the presence of occlusion
• Primary-angle closure (the term glaucoma is added when glaucomatous optic neuropathy is present):
  • Occludable drainage angle plus signs that the peripheral iris has obstructed the trabecular meshwork (e.g., elevated IOP, lens opacities)
• Chronic angle-closure glaucoma: Refers to an eye with permanent closure of areas of the anterior chamber angle by peripheral anterior synechiae

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

• Leading cause of blindness is glaucoma of this type
• Age >40
• Female > Male
• Inuit and Asian > African and European
• Most common form of glaucoma worldwide, but only 10% of glaucoma in the US

Prevalence
Acute-angle closure glaucoma occurs in 1 in 1,000 Caucasians; 1 in 100 Asians; 2–4 in 100 Eskimos (lifetime)

Risk Factors

• Hyperopia
• Age >40
• Shallow anterior chamber
• Female gender
• Family history of angle closure
• Asian or Inuit descent
• Pseudoexfoliation
• Short axial length
• Thick crystalline lens
• Medications that may induce angle-closure glaucoma:
  • ACE inhibitors (rare), adrenergic agonists (albuterol), anticholinergics, antihistamines, antidepressants including SSRIs and TCAs, cholinergic agents (pilocarpine), noncatecholamine adrenergic agonists, sulfa-based drugs, topiramate,warfarin (rare)

Genetics
Polygenic inheritance: 1st-degree relatives have a 2–5% lifetime risk.

General Prevention

• Routine eye exam with gonioscopy for high-risk populations
• US Preventive Services Task Force: Insufficient evidence to recommend for or against screening adults for glaucoma

Pathophysiology

• Peripheral iris apposition to the trabecular meshwork obstructs the outflow of aqueous humor through the trabecular meshwork, which causes elevation in IOP.
• The underlying mechanism is anterior lens displacement or other anatomic abnormality, leading to pupillary block in which aqueous humor egress through the pupil is limited. This causes pressure to build posterior to the iris, leading to anterior iris displacement.

Etiology

Predisposing ocular anatomy

Commonly Associated Conditions

• Cataract
• Hyperopia
• Microphthalmos
• Systemic hypertension