EURETINA 2026: Why half-dose PDT leads the treatment of central serous chorioretinopathy

At the 26th EURETINA Congress in Vienna, Austria, Elon van Dijk, MD, PhD, FEBOphth, reviewed the randomised controlled trial (RCT) evidence on treating central serous chorioretinopathy (CSC). He is a medical retina specialist and vitreoretinal surgeon at the Rotterdam Eye Hospital and Leiden University Medical Center in the Netherlands. He urged clinicians to secure access to half-dose photodynamic therapy (PDT) in their countries.

Why complete fluid resolution matters

In CSC, subretinal fluid accumulates, usually under the fovea. Van Dijk noted that the exact pathogenesis remains unknown. Steroids are related to the development of the disease, he said, regardless of the dose, the mode of administration or the type of medication.

He stressed that clinicians should aim to eliminate all subretinal fluid. Even with partial resolution, fluid can persist and cause prolonged damage to the outer retina and retinal pigment epithelium. Because fluid in CSC can wax and wane, he explained, only RCTs can separate a true treatment effect from the disease's natural fluctuation.

What the trials show

Van Dijk summarised 3 RCTs in chronic CSC:

PLACE: Half-dose PDT outperformed micropulse laser treatment for both anatomy and vision, in the short and long term.

SPECTRA: Half-dose PDT also proved superior to the mineralocorticoid receptor antagonist eplerenone (Inspra; Pfizer).

VICI: This UK trial found that eplerenone produced results similar to placebo. Fluid resolved in 30% of the placebo group, and in a lower proportion of patients treated with eplerenone.

Based on these findings, he said eplerenone and spironolactone (Aldactone; Pfizer) have no place in the treatment of CSC.

Acute CSC and the role of the choroid

No RCTs have been conducted in acute CSC, which van Dijk called an important topic to address. Spontaneous resolution is somewhat more likely in acute disease, but some patients still need treatment. Larger retrospective studies support half-dose PDT as the treatment of choice in that subset, such as patients who need relatively rapid visual recovery.

Van Dijk attributed PDT's efficacy to its effect on choroidal abnormalities. These are far more widespread than abnormalities in the retinal pigment epithelium and under the retina, so targeting them broadly helps achieve a completely dry retina.

Towards personalised treatment

Van Dijk said a calculation that predicts which patients will resolve spontaneously would be extremely useful. It could draw on multimodal imaging, clinical features and potentially genetic profile, and would also estimate short- and long-term prognosis. He noted that the current shortage of verteporfin (Visudyne; Bausch + Lomb) makes careful patient selection even more important.

His key message was that clinicians “should try everything you can to make PDT available in your country.” He acknowledged that reimbursement and drug supply can be challenging, and offered to help colleagues who need support with logistics or with contacting their government.