Treatment of Central Serous Chorioretinopathy
For acute CSC presenting within the first 4 months, observation is the standard approach unless the patient requires rapid visual recovery for professional reasons, has recurrent episodes, or bilateral disease—in which case ICGA- and FA-guided half-dose photodynamic therapy should be performed immediately. 1, 2
Acute Central Serous Chorioretinopathy (aCSC)
Initial Management Strategy
Observation for 4 months is recommended for first-time acute cases with a single focal leak and minimal RPE changes (less than 1-disc area), given the high rate of spontaneous subretinal fluid resolution during this timeframe. 1, 2
OCT imaging is critical for diagnosis and monitoring, as subretinal fluid can be too shallow to detect on slit-lamp biomicroscopy, and residual fluid can cause photoreceptor and RPE atrophy leading to vision loss over years. 1
Indications for Immediate Treatment (No Observation Period)
Proceed directly to half-dose PDT without observation in these specific scenarios:
- Patients requiring rapid visual recovery for professional reasons 1, 2
- Recurrent active aCSC (previous episodes of subretinal fluid) 1, 2
- Bilateral active disease 1, 2
Treatment Options for Acute CSC
Half-dose PDT is the treatment of choice when intervention is indicated, achieving faster subretinal fluid resolution, more rapid recovery of retinal sensitivity, and lower recurrence rates (25%) compared to spontaneous resolution (51.2% recurrence). 1, 2
Technical Specifications for PDT:
- Use ICGA-guided half-dose PDT to optimally treat underlying choroidal abnormalities 1
- Target hyperfluorescent areas on ICGA that correspond to focal leakage on FA and subretinal fluid on OCT 1, 2
- Half-dose PDT is preferred over half-fluence or half-time PDT, as large RCTs demonstrate high efficacy in chronic CSC with minimized local and systemic side effects 1
- Half-dose protocol allows one vial of verteporfin to treat two patients, reducing costs and increasing availability 1
Argon Laser Photocoagulation:
- Use only when focal leak on FA is located at a safe distance from the fovea 1
- Do not use thermal laser photocoagulation for underlying choroidal abnormalities 1
- Carries significant risks: symptomatic paracentral scotoma, macular neovascularization, and chorioretinal adhesion with secondary intraretinal cystoid fluid 1, 2
Important Caveat
Opting for a short observation period of a few months does not appear to affect longer-term outcomes in aCSC, so the decision to observe versus treat early should be based on the specific clinical scenarios outlined above. 1
Chronic Central Serous Chorioretinopathy (cCSC)
Definition and Treatment Goals
Chronic CSC is defined by persistent subretinal fluid on OCT for longer than 4 months, with more than 1-2 disc areas of atrophic RPE changes, and focal or diffuse leakage on FA with hyperfluorescent choroidal abnormalities on ICGA. 1, 2
The treatment goal is to prevent irreversible photoreceptor damage and vision loss by achieving complete subretinal fluid resolution and reversing photoreceptor/RPE dysfunction, as persistent subretinal fluid leads to irreversible vision loss and reduced quality of life. 1, 2
First-Line Treatment
ICGA- and FA-guided half-dose (or half-fluence) PDT is the first-line treatment for chronic CSC, with large RCTs demonstrating 21-100% complete subretinal fluid resolution rates and superior functional improvement compared to other treatments. 1, 2
Evidence Supporting PDT Superiority:
- The PLACE trial showed half-dose PDT was superior to high-density subthreshold micropulse laser (HSML), with complete subretinal fluid resolution in 67% versus 29% of patients at 7-8 months. 1
- The SPECTRA trial demonstrated half-dose PDT led to significantly more complete subretinal fluid resolution and functional improvement compared to eplerenone. 1
- PDT provides faster subretinal fluid resolution, more rapid recovery of retinal sensitivity, and higher best-corrected visual acuity compared to observation. 1, 3, 4
Treatment Algorithm for Persistent Subretinal Fluid After Initial PDT
If subretinal fluid persists after initial half-dose PDT:
- Re-treatment with another half-dose or half-fluence PDT guided by FA/ICGA 1, 2
- Full-dose with full-fluence PDT may also be considered 1
- High-density subthreshold micropulse laser (inferior to PDT but acceptable alternative) 1, 2
- Mineralocorticoid receptor antagonist (limited evidence) 1, 2
- Conservative observation if only small amount of residual subretinal fluid 1, 2
Alternative Treatments When PDT is Unavailable
Conventional argon laser photocoagulation can be used for chronic CSC with focal, non-central leakage on angiography when PDT is unavailable, but only when the leak is at a safe distance from the fovea. 1, 4
High-density subthreshold micropulse laser has been studied but shows inferior results compared to half-dose PDT in both focal and diffuse phenotypes of chronic CSC. 1, 2
Mineralocorticoid receptor antagonists (eplerenone, spironolactone) may be considered when PDT is unavailable or as adjunctive therapy, although the VICI trial showed non-superiority of eplerenone compared to placebo. 1, 2, 5
Selective retina therapy (SRT) has shown variable results, but the evidence quality is insufficient to recommend it over PDT. 2, 4
Anti-VEGF agents are not effective for chronic CSC in the absence of choroidal neovascularization. 4, 6
CSC with Concurrent Macular Neovascularization
When macular neovascularization is present (detected using OCT, OCT-A, FA, and ICGA):
- Treat with half-dose/half-fluence PDT and/or intravitreal anti-VEGF injections 1
- When a neovascular component of polypoidal choroidal vasculopathy (aneurysmal type 1 neovascularization) is present, PDT (either full-dose, half-dose, or half-fluence) can be added to anti-VEGF treatment 1
Critical Considerations
Corticosteroid Use
If the patient is currently taking corticosteroids, discuss stopping their use prior to treatment, as corticosteroids are a known risk factor for CSC. 1, 7
Post-PDT Precautions
- Patients must avoid direct sunlight and UV radiation for 48-72 hours after receiving PDT 3
- Wear protective clothing and stay out of the sun for 72 hours following the procedure 3
Follow-up Timing
- Follow-up imaging at 4-6 weeks post-treatment is appropriate to assess treatment response 3
- For observation cases, follow-up with OCT after 1-3 months to assess for complete subretinal fluid resolution 1