Subthreshold Micropulse Treatment Laser versus Half-Dose Photo Dynamic Therapy for the Chronic Central Serous Chorioretinopathy with Parafoveal or Subfoveal Leakage STML versus PDT for Treatment of Chronic CSC

Evaluating Photodynamic Therapy vs. Subthreshold Micropulse Laser for Central Serous Chorioretinopathy: A Retrospective Study

BACKGROUND

Our study aims to compare the efficacy of half-dose photodynamic therapy with verteporfin (PDT) and subthreshold micropulse laser (SML) in patients with central serous chorioretinopathy (CSCR) with regards to subretinal fluid (SRF) resorption, visual acuity (VA), and central subfield thickness (CST).

PATIENTS AND METHODS

We conducted a retrospective multicentre clinical study at the Departments of Ophthalmology at the University Hospital Zurich and Stadtspital Zürich, Switzerland. The study included patients with acute and chronic CSCR who underwent PDT, SML, or both sequentially between June 1, 2020 and December 31, 2023. The primary outcome was the reduction in SRF at three and six months post-treatment. The secondary outcomes included change in CST VA at the same intervals.

RESULTS

A total of eighty-one eyes were analysed (33 PDT, 35 SML, thirteen combined). SRF reduction was statistically significant at both three and six months in the PDT (p < 0.001) and SML groups (p < 0.001). The combined treatment group showed a significant reduction in SRF only at six months (p = 0.001). At three months, PDT resulted in a significantly greater SRF reduction than the combined group.

CONCLUSIONS

Both PDT and SML demonstrated improvements in SRF, CST and VA, with SML presenting as a comparable alternative, particularly in cases where access to verteporfin is limited.

[Treatment of central serous chorioretinopathy in comparison-Micropulse laser versus photodynamic therapy]

The therapeutic management of central serous chorioretinopathy (CSC) remains challenging. Although CSC shows a high rate of self-resorption, frequent recurrences or chronification of the disease can result in irreversible loss of vision. Low-dose photodynamic therapy (half-dose or half-fluence PDT) represents the current standard of care for CSC, although regenerative laser procedures may also offer a safe and effective alternative for the treatment of CSC.

Laser Treatment of Central Serous Chorioretinopathy - An Update

Laser treatment has been a mainstay for management of central serous chorioretinopathy for a few decades. Different types of lasers have been used and non-damaging retinal laser is the most recent option. The aim of this review is to provide an update on this form of treatment, based on the research published during last 5 years, in comparison with earlier studies published. A MEDLINE database search was performed with a combination of the following terms: central serous chorioretinopathy and laser photocoagulation or subthreshold laser or subthreshold micropulse laser or nanosecond laser or microsecond laser or end-point management or photodynamic therapy. Results were analyzed separately for each modality of laser treatment. Reports published in recent years confirm findings of previous research and do not distinguish treatments of this clinical entity. Among all analyzed laser options, photodynamic therapy provides the fastest and most prominent morphological improvements, including subretinal fluid resorption and reduction of choroidal thickness. This modality is also associated with fewer recurrences than with other treatments. Subthreshold micropulse laser allows the physician to maintain and, in selected cases, improve the patient's vision. Conventional photocoagulation is still effective, especially with the introduction of navigated laser systems. Despite the availability of variable laser treatment options, long-term functional improvements in chronic cases are minor for each modality. Long-lasting central serous chorioretinopathy cases with significantly altered retinal morphology do not usually present with functional improvement, despite satisfactory morphological outcomes. Early initiation of treatment has the potential to prevent visual loss and to improve the patient's quality of life.

Efficacy of Subthreshold Micropulse Laser for Central Serous Chorioretinopathy

PURPOSE

To evaluate the efficacy of a subthreshold micropulse laser (SML) in patients with central serous chorioretinopathy (CSCR).

METHODS

Retrospective clinical study conducted at the Departments of Ophthalmology at a university and a municipal hospital in Zurich, Switzerland. We enrolled acute and chronic CSCR patients with persistent subretinal fluid (SRF) treated with SML. Two treatment protocols (fluorescein/indocyanine green angiography or optical coherence tomography guided) were evaluated for efficacy after 3 and 6 months. The primary outcomes of the study were reduction and percentage of eyes with complete resolution of SRF 3 and 6 months after SML treatment. Secondary endpoints included changes in central subfield thickness (CST) and visual acuity (VA) after 3 and 6 months.

RESULTS

The study involved 37 eyes (35 patients, 48.6% chronic). A statistically significant reduction in SRF height and CST could be shown, irrespective of SRF duration, type of CSCR, or chosen guidance after 3 and 6 months: SRF - 40 µm (p < 0.01), CST - 52 µm (p < 0.01). Percentage of eyes with complete resolution of fluid at 3 and 6 months after SML were 24.3 and 21.6%, respectively. No statistically significant functional improvement (VA) could be shown. Multivariable regression and linear mixed regression analyses did not identify statistically significant differences in SRF reduction, CMT change, or VA improvement with respect to the type of CSCR or the treatment plan used (p > 0.05).

CONCLUSION

The effectiveness of SML in CSCR is under continuous debate. Our study findings demonstrate structural but only little functional changes with SML. In view of the shortage of verteporfin for photodynamic therapy, SML remains an important therapeutic option for CSCR patients.

Bilateral Focal Choroidal Excavation and Central Serous Chorioretinopathy Coexisting in a Male Patient

Background

Here, we report a case of a male patient with bilateral focal choroidal excavation (FCE) and central serous chorioretinopathy (CSC). A 33-year-old man complained of mild blurring of vision in the right eye. Optical coherence tomography (OCT) revealed FCE in both eyes, with subretinal fluid in both eyes and serous pigment epithelial detachment in the right eye. Standard laser fluence (50 J/cm2) was used in the right eye, and a subthreshold micropulse laser (SML) was simultaneously used in the left eye. Follow-up visits were recommended. At his last visit (5 months after treatment), the visual acuity was 16/20 in the right eye and 20/20 in the left eye and OCT showed a completed resolution of SRF.

Conclusion

FCE is defined as a localized depression of the choroid detected by OCT. It may be congenital or acquired secondarily. We present a case of uncommon focal choroidal excavation and central serous chorioretinopathy (CSC) coexisting in both eyes at a relatively young age in which visual acuity was improved and subretinal fluid (SRF) completely resolved with laser treatment. Timely treatment can promote SRF absorption and improve vision.