creation date: 2026-06-16 19:25
tags: Pathologies
Open-Angle Glaucoma
Background
Definitions
Open-angle glaucoma is a type of glaucoma characterized by a progressive optic nerve damage.
Glaucomas are optic neuropathies that involves the atrophy of the optic nerve head and is associated with increased intraocular pressure.
Risk Factors
Risk factors for open-angle glaucoma are:
- Age (>40)
- Black or White race (in contrast, angle-closure glaucoma is more common in East Asian populations)
- Family history
- Diabetes
- Hypertension
- Elevated intraocular pressure (IOP)
Pathogenesis
In normal physiology, aqueous humour is produced by the ciliary body, flows through the pupil, and exits the eye through the anterior chamber angle. The balance of fluid production and drainage determines intraocular pressure (IOP).
Primary open-angle glaucoma is the most common type, in which increased resistance to drainage in the trabecular meshwork, the IOP gradually increases. Elevated IOP damages the optic nerve and causes progressive visual loss.
Secondary open-angle glaucoma is much less common but can have various causes.
- Uveitis
- Trauma
- Glucocorticoid therapy
Clinical Presentation
Signs & Symptoms
Many individuals with open-angle glaucoma are asymptomatic or rarely symptomatic and thus only incidentally detected during ophthalmic examination.
Progression of vision loss occurs over a median of 70 years (mean of 25 years; small subset of rapid progression):
- Visual field loss (may not even be noticeable to patient to point of 10-20 degrees)
- Central visual loss
IOP may be elevated but not all patients with elevated IOP will develop glaucoma.
History & Physical Exam
Diagnosis
Criteria
Diagnosis is made through an ophthalmic examination with:
- Characteristic nerve damage on fundus exam
- Visual field testing
- IOP measurement (note, presence of elevated IOP is supportive but not necessary)
Work-up
Screening
Screening by an ophthalmologist or optometrist is indicated for patients with:
- Abnormal cupping on fundoscopy
- Risk factors (eg. age >40)
- Elevated IOP
Differential
Red Flags / Complications
If left untreated, glaucoma can result in irreversible visual field loss and ultimately vision loss.
Management
Management of secondary open-angle glaucoma should include treatment of etiology.
The goal of therapy is to lower IOP. This may be through:
- Pharmacologic options
- Laser therapy (trabeculoplasty)
- Surgery (trabeculectomy)
Pharmacotherapy options include:
- Prostaglandins (preferred)
- Beta blockers