What is the recommended treatment plan for a patient diagnosed with glaucoma?

Treatment Plan for Glaucoma

For patients with confirmed primary open-angle glaucoma (POAG), initiate IOP-lowering therapy immediately with a target reduction of at least 25% from baseline IOP, using either topical prostaglandin analogs or beta-blockers as first-line monotherapy, with laser trabeculoplasty as an alternative primary option. 1, 2

Initial Assessment and Risk Stratification

Before initiating treatment, complete the following diagnostic workup:

• IOP measurement with multiple readings at different times of day to establish baseline 2
• Central corneal thickness (CCT) measurement—patients with IOP ≥26 mmHg and CCT ≤555 μm have a 36% risk of progression versus 2% risk for those with IOP <24 mmHg and CCT >588 μm 1
• Optic nerve head (ONH) examination with stereoscopic photography for baseline documentation 1, 2
• Optical coherence tomography (OCT) of ONH, RNFL, and macular ganglion cell complex 1, 2
• Visual field testing using standard automated perimetry (24-2 or 30-2 pattern) 1, 2
• Gonioscopy to confirm open angles and exclude secondary causes 2

Treatment Initiation

Target IOP Setting

Set initial target IOP at 25% or lower than baseline pretreatment IOP, as this reduction has been proven to slow POAG progression 1, 2. Adjust target downward for:

• More severe optic nerve damage at presentation 1
• Rapid progression documented on serial testing 1
• High-risk features including disc hemorrhages, thin CCT, or family history 1
• Presence of beta zone peripapillary atrophy (requires 20-25% reduction minimum) 3

First-Line Pharmacotherapy

Begin with topical prostaglandin analog monotherapy (latanoprost, bimatoprost, travoprost, or tafluprost) as these provide the most robust IOP reduction with once-daily dosing 4, 5. Alternative first-line option is a topical beta-blocker (timolol 0.5%) if prostaglandins are contraindicated 4, 5, 6.

For chronic open-angle glaucoma specifically, acetazolamide 250 mg to 1 g per 24 hours in divided doses can be used as adjunctive therapy, though doses exceeding 1 g per 24 hours do not produce increased effect 7.

Laser Trabeculoplasty as Primary Therapy

Consider selective laser trabeculoplasty (SLT) or argon laser trabeculoplasty as primary treatment when medication adherence, cost, convenience, side effects, or risks are concerns 1, 5. This is particularly appropriate for patients who struggle with drop administration 1.

Monitoring Protocol

Initial Phase (First 2 Years)

• Follow-up every 3-6 months until stability is demonstrated 2, 3
• Perform three visual field tests per year during the first 2 years to detect rapid progression 3
• Each visit must include:
  • Visual acuity measurement 1, 2
  • Slit-lamp biomicroscopy 1, 2
  • IOP measurement 1, 2
  • Periodic ONH and RNFL evaluation 1, 2
  • Assessment for disc hemorrhages via photography 3

Maintenance Phase (After Stability Established)

• Follow-up every 6-12 months once IOP is stable and no progression is documented 8
• Continue monitoring IOP control, medication adherence, adverse effects, and optic nerve/visual field status 8

Treatment Escalation Algorithm

When to Intensify Therapy

Adjust therapy downward (lower target IOP) immediately if: 1, 3

• Progressive optic disc, imaging, or visual field changes occur despite achieving initial target IOP
• Target IOP is not achieved with current regimen
• Patient shows intolerance or non-adherence to current medications

Escalation Options

1. Add second topical agent from different class:

   • Alpha-2 agonists (brimonidine) as second-line 4, 5
   • Topical carbonic anhydrase inhibitors (dorzolamide, brinzolamide) as second-line 4, 5
   • Fixed combination medications (e.g., bimatoprost/timolol) for refractory cases 9

2. Consider laser trabeculoplasty if not already performed 1

3. Refer for incisional surgery (trabeculectomy, tube shunt, or cyclodestruction) when medical and laser therapy fail 5, 10

Critical Pitfalls to Avoid

• Do not delay treatment in patients with confirmed optic nerve deterioration, RNFL loss, or visual field changes—these patients have progressed from "suspect" to POAG and require immediate therapy 1
• Do not use brimonidine in nursing mothers due to risk of infant apnea 8
• Do not assume normal IOP excludes glaucoma—normal-tension glaucoma exists and still requires IOP reduction 5, 6
• Do not rely on IOP measurement alone for monitoring—both structural imaging and visual field testing are essential as some patients show visual field loss without corresponding structural changes and vice versa 3
• Do not increase acetazolamide beyond 1 g per 24 hours as higher doses do not produce increased effect 7

Patient Education and Adherence

Educate patients that glaucoma is chronic and asymptomatic early, requiring lifelong treatment and monitoring 1, 2. Many patients struggle with drop administration—consider demonstrating technique and involving caregivers 1. Discuss that glaucoma significantly impacts quality of life including employment, driving, reading, and risk of falls 1, 2.