What is the initial approach to treating central serous chorioretinopathy?

Initial Approach to Treating Central Serous Chorioretinopathy

For acute central serous chorioretinopathy (aCSC) presenting within the first 2-4 months, observation for 4 months is the standard initial approach, unless the patient requires rapid visual recovery for professional reasons, has recurrent episodes, or bilateral disease—in which case immediate half-dose photodynamic therapy (PDT) should be performed. 1, 2

Acute CSC Management Algorithm

First-Time Presentation with Unilateral Disease

Observation is the preferred initial strategy because spontaneous subretinal fluid (SRF) resolution occurs in 70-80% of cases within 3-4 months 3, 4. This approach is justified by the disease's relatively benign natural course and the high rate of spontaneous resolution 3.

• Monitor with OCT every 1-3 months to assess for residual SRF and photoreceptor damage 2
• Continue observation up to 4 months from symptom onset 3, 1
• Do not wait the full 4 months if OCT reveals outer segment atrophy or granular debris in the subretinal space, as these indicate ongoing photoreceptor damage requiring immediate intervention 2

Immediate Treatment Indications (Skip Observation)

Proceed directly to ICGA- and FA-guided half-dose PDT if any of the following are present 1, 2:

• Highly symptomatic patients requiring rapid visual rehabilitation for professional reasons 3, 1
• Recurrent episodes of acute CSC 1, 2
• Bilateral active disease 1
• Evidence of photoreceptor damage on OCT (outer segment atrophy, granular debris) 2

Why Half-Dose PDT Over Observation When Treatment Is Needed

Half-dose PDT achieves faster SRF resolution, more rapid recovery of retinal sensitivity, and significantly lower recurrence rates (25%) compared to spontaneous resolution (51.2%) 1, 5. A randomized trial demonstrated that while 12-month visual outcomes were similar between immediate PDT and 3-month observation, PDT resulted in faster visual recovery and significantly improved metamorphopsia at 3 months 6.

Technical Specifications for PDT

• Use ICGA- and FA-guided targeting of hyperfluorescent areas corresponding to focal leakage and SRF on OCT 1
• Half-dose verteporfin (3 mg/m²) is preferred over half-fluence or half-time protocols 1, 2
• Target the hyperfluorescent areas on ICGA that correspond to the area of focal leakage on FA and SRF on OCT 2

Alternative: Focal Laser Photocoagulation

Argon laser photocoagulation can only be used when focal leakage on FA is located at a safe distance from the fovea (extrafoveal), but this carries significant risks 1:

• Risk of paracentral scotoma 1
• Risk of macular neovascularization (MNV) 1
• Risk of chorioretinal adhesion with secondary cystoid changes 1

Chronic CSC Management (>4-6 Months Duration)

Definition and Diagnostic Criteria

Chronic CSC is defined by 3, 1:

• Persistent SRF on OCT for longer than 4-6 months
• More than 1-2 disc areas of atrophic RPE changes
• One or more focal leakage points on FA
• Hyperfluorescent choroidal abnormalities on ICGA

First-Line Treatment

ICGA- and FA-guided half-dose (or half-fluence) PDT is the first-line treatment for chronic CSC, with large randomized controlled trials demonstrating 21-100% complete SRF resolution rates 1. This represents the strongest evidence-based recommendation for chronic disease 3, 2.

If SRF Persists After Initial PDT

Consider one of the following approaches 3, 1:

1. Re-PDT guided by FA/ICGA
2. High-density micropulse laser treatment (though this shows inferior results compared to half-dose PDT) 1
3. Mineralocorticoid receptor antagonist (eplerenone or spironolactone), though evidence is limited 1, 2
4. Observation if only minimal residual SRF remains 3

Critical Management Considerations

Corticosteroid Use

Always discuss cessation of corticosteroid use if the patient is currently taking any form (systemic, topical, inhaled, or intranasal), as steroid-induced CSC may not resolve without dose reduction or discontinuation 2, 4. Corticosteroid therapy is considered a major risk factor for CSC 4.

Common Pitfalls to Avoid

• Do not delay treatment in patients with evidence of photoreceptor damage on OCT, even if within the 4-month observation window 2
• Do not use full-dose PDT, as half-dose achieves similar efficacy with fewer side effects 1, 2
• Do not use focal argon laser near the fovea, as this carries unacceptable risks of permanent scotoma and neovascularization 1
• Do not rely solely on mineralocorticoid receptor antagonists as first-line therapy for chronic CSC, as recent evidence (VICI trial) has resized their role 7

Monitoring During Observation Period

• Perform OCT every 1-3 months to detect early photoreceptor damage 2
• Watch for outer segment atrophy or granular debris, which mandate immediate treatment 2
• Assess for bilateral involvement, which changes management to immediate PDT 1