Treatment for Glaucoma Symptoms
The primary treatment for glaucoma symptoms is lowering intraocular pressure (IOP) through medications, laser therapy, or surgery, with prostaglandin analogs being the first-line medical therapy due to their superior efficacy in reducing IOP by 6-8 mmHg from baseline, excellent tolerability, and once-daily dosing regimen. 1
Understanding Glaucoma
Glaucoma is a chronic, progressive optic neuropathy characterized by:
- Damage to the optic nerve
- Loss of retinal ganglion cells and their axons
- Progressive visual field loss
The main goals of glaucoma management are:
- Control of IOP in the target range
- Maintaining stable optic nerve/retinal nerve fiber layer (RNFL) status
- Preserving stable visual fields 2
Treatment Algorithm
Step 1: Establish Target IOP
- Initial target: 20-25% reduction from baseline IOP 1
- More aggressive targets (>25% reduction) for:
- Severe optic nerve damage
- Rapidly progressing disease
- Additional risk factors (family history, older age, disc hemorrhages) 2
Step 2: First-Line Treatment Options
Medical Therapy
Prostaglandin analogs (first choice):
- Once-daily dosing
- Superior efficacy (6-8 mmHg reduction)
- Excellent tolerability
- Side effects: conjunctival hyperemia, increased iris pigmentation 1
Beta-blockers (alternative first-line or second-line):
- Once or twice daily dosing
- Avoid nighttime dosing (reduces efficacy and may contribute to visual field progression)
- Contraindications: bronchial asthma, COPD, bradycardia, heart block 3
Laser Therapy
- Selective Laser Trabeculoplasty (SLT):
- As effective as medications for first-line therapy
- May be repeatable due to less tissue damage
- Consider as alternative to adding a second medication 1
Step 3: If Target IOP Not Achieved
Add a second medication from a different class:
- Beta-blockers
- Alpha-2 agonists
- Carbonic anhydrase inhibitors
- Consider fixed-combination products to improve adherence 1
Oral carbonic anhydrase inhibitors (e.g., acetazolamide):
- For more aggressive IOP lowering
- Dosage: 250 mg to 1 g per 24 hours in divided doses
- Not recommended to exceed 1 g per 24 hours 4
Surgical options if medical/laser therapy fails:
- Trabeculectomy
- Glaucoma drainage devices
- Minimally invasive glaucoma surgery (MIGS) 1
Special Considerations
Acute Angle-Closure Glaucoma
- Requires immediate intervention:
- Beta-adrenergic antagonists
- Alpha-2 adrenergic agonists
- Carbonic anhydrase inhibitors (oral/IV)
- Hyperosmotic agents
- Followed by definitive treatment with laser peripheral iridotomy 1
- Note: Miotics like pilocarpine may be ineffective when IOP is markedly elevated 1
Glaucoma Suspects
- Monitor for:
- Structural changes in optic disc and retina
- Functional changes of optic nerve via visual field assessment
- IOP changes 2
- Consider treatment if:
- Very high IOP where optic nerve damage is likely
- Additional risk factors present (older age, family history, African ancestry, thin central cornea) 2
Common Pitfalls to Avoid
Inadequate monitoring: Regular assessment of IOP, optic nerve structure, and visual field function is essential 1
Inappropriate beta-blocker use: Using beta-blockers at night reduces efficacy and may contribute to nocturnal hypotension 1
Overtreatment: Not all glaucoma suspects require treatment; in OHTS, more than 90% of patients with ocular hypertension did not progress to glaucoma over 5 years 2
Medication side effects:
Neglecting adherence: Discuss importance of adherence to treatment and regular ophthalmologist visits 5
By following this structured approach to managing glaucoma symptoms, clinicians can effectively reduce IOP, slow disease progression, and preserve patients' vision and quality of life.