The Effect of Selective Retina Therapy with Automatic Real-Time Feedback-Controlled Dosimetry for Chronic Central Serous Chorioretinopathy: A Randomized, Open-Label, Controlled Clinical Trial

Selective retina therapy with real-time feedback-controlled technology in central serous chorioretinopathy: a 24-month follow-up real-world prospective study

OBJECTIVE

Although central serous chorioretinopathy (CSC) treatment using selective retinal therapy (SRT) has presented favourable outcomes, no long-term studies with a real-world clinical practice regimen have been conducted.

METHODS AND ANALYSIS

We performed a long-term assessment of CSC treatment using SRT with real-time feedback (RTF) technology. 50 patients (53 eyes) with CSC and more than a 1-month symptom duration were recruited and treated with SRT using a 1.7 µs pulse width, 527 nm neodymium-doped yttrium lithium fluoride (Nd:YLF) laser equipped with an RTF system.

RESULTS

After 6 months of treatment, complete subretinal fluid resolution was achieved in 62% of the eyes. The mean best-corrected visual acuity (BCVA; logarithm of the minimum angle of resolution, mean±SD) improved slightly from 0.15±0.18 at baseline to 0.12±0.21 at 6 months (p=0.062). The central retinal thickness (CRT; mean±SD) was reduced significantly from 350.6±100.1 µm at baseline to 268.2±70.6 µm at 6 months (p<0.001). Long-term follow-up revealed significant improvements in BCVA, from 9 months until 24 months, and in CRT, from 1 month until 24 months. No treatment-related adverse events were observed during the 24-month follow-up period.

CONCLUSION

Our results suggest that SRT with RTF technology is a long-term safe treatment with anatomical improvement for patients with CSC.

Randomized controlled trials in central serous chorioretinopathy: A review

Central serous chorioretinopathy (CSCR), a common chorioretinal disease, presents with a myriad of manifestations. Acute CSCR presents with localized neurosensory detachment whereas chronic CSCR may show widespread retinal pigment epithelium (RPE) changes, chronic shallow subretinal fluid, and choroidal neovascularization (CNV) suggestive of a variable natural history leading to suboptimal visual outcomes. Even though multiple treatment options including laser photocoagulation, photodynamic therapy, micropulse laser, anti-vascular endothelial growth factors, and systemic drugs (spironolactone, eplerenone, melatonin, mifepristone) are available, there is an absence of any standardized treatment protocol or gold standard treatment modality. Moreover, their performance compared to observation especially in acute CSCR is still debatable. Compared to other chorioretinal diseases such as age-related macular degeneration, diabetic retinopathy, diabetic macular oedema, and retinal vein occlusion, there is a relative dearth of randomized controlled trials in CSCR. Multiple inconsistencies including reliance on history of disease duration, variable inclusion criteria/disease descriptors/study endpoints, and availability of multiple treatment modalities lead to difficulties in designing RCTs. A consensus-based treatment protocol, therefore, is still elusive. We reviewed the literature and compiled the list of papers published to date, wherein we analyse and compare the inclusion criteria, imaging modalities, study endpoints, study duration, and study results. Correcting these discrepancies and deficiencies will help standardize future study designs, facilitating a next step toward a standardized treatment protocol.

Comparing treatment outcomes in randomized controlled trials of central serous chorioretinopathy

PURPOSE

To perform a qualitative analysis of outcomes published from randomized controlled trials (RCTs) on central serous chorioretinopathy (CSCR) from 1979 to 2022.

DESIGN

Systematic review.

METHODS

All RCTs (including both therapeutic and non-therapeutic interventions) on CSCR available online till July 2022 were included after an electronic search in multiple databases such as PubMed, CENTRAL, MEDLINE, EMBASE, BIOSIS, Scopus, and Cochrane database. We analyzed and compared the inclusion criteria, imaging modalities, study endpoints, duration, and the results of the study.

RESULTS

The literature search yielded 498 potential publications. After excluding duplicate studies and studies that met clear exclusion criteria, 64 were screened for further evaluation, of which 7 were removed due to a lack of necessary inclusion criteria. A total of 57 eligible studies are described in this review.

CONCLUSION

This review provides a comparative overview of key outcomes reported between RCTs investigating CSCR. We describe the current landscape of treatment modalities for CSCR and note the discrepancies between results in these published studies. Challenges arise when attempting to compare similar study designs without comparable outcome measures (i.e., clinical vs. structural) which may limit the overall evidence presented. To mitigate this issue, we present the collected data from each study in tables detailing the measures that are and are not assessed in each publication.

Long-Term Multimodal Imaging Analysis of Selective Retina Therapy Laser Lesions

This study evaluates the long-term effects of selective retina therapy (SRT) on the retinal pigment epithelium (RPE) and neuroretina in patients with central serous chorioretinopathy. SRT was performed on 36 patients using a Nd:YLF-Laser at 527 nm (R:GEN®, Lutronic, Goyang-Si, Republic of Korea). A total of 994 titration spots were examined using up to three years’ multimodal imaging. Leakage in fluorescein angiography (FA) was observed after SRT in 523 lesions and resolved after one month. SRT lesions were not visible clinically, but appeared as brightly reflective areas in infrared and multicolor images. Normal morphology was observed in optical coherence tomography (OCT) immediately after SRT. After one month, thickening of the RPE and interdigitation zone changes were seen and disappeared after 539 ± 308 days. No RPE atrophies occurred during the observation period. Decreased fundus autofluorescence (FAF) was mostly observed directly after SRT followed by increased FAF at one month, which faded over time. A significant decrease in the number of visible lesions in the FA and FAF was observed within the three-year follow-up. OCT findings are consistent with animal studies showing SRT-related defect closure by hypertrophy and migration of neighboring cells without RPE atrophy or photoreceptor damage. This suggests that SRT is a safe treatment option for macular diseases and does not lead to retinal atrophy.

Comparing interventions for chronic central serous chorioretinopathy: A network meta-analysis

We compare efficacy of treatments for chronic central serous chorioretinopathy (CSCR) > 3 months. Four treatment classes were considered: photodynamic therapy (PDT), subthreshold laser therapies (SLT), mineralocorticoid receptor antagonists (MRA) and anti-vascular endothelial growth factor (anti-VEGF) agents. Pairwise and network meta-analyses of the primary outcomes (complete resolution of subretinal fluid (SRF), mean change in best corrected visual acuity (BCVA) (logMAR) and mean change in SRF) and secondary outcomes (mean change in central retinal thickness, and central choroidal thickness (μm), recurrence of SRF, and adverse events) at 3, 6 and 12 months were compared. Confidence in Network Meta-Analysis (CINeMA) informed the certainty of NMA evidence. Eleven RCTs of 458 eyes (450 patients) were included. NMA at 3 months showed that both PDT and SLT were superior to control for resolution of SRF (OR 4.83; 95% CI 1.72 to 13.55 and 2.27; 1.14 to 4.49, respectively) and SLT was superior to control for improving BCVA (MD -0.10; -0.17 to -0.04). PDT was superior to SLT for improving CRT (MD-42.88; -75.27 to -10.50). On probability ranking, PDT and SLT were consistently the best-ranked treatments for each outcome at 3 months, but low confidence of evidence and paucity of studies preclude definitive conclusions.

Comparative efficacy of treatments for chronic central serous chorioretinopathy: A systematic review with network meta-analyses

Treatment of chronic central serous chorioretinopathy (cCSC) remains a topic of controversy. As cCSC is a disease that can wax and wane, treatment efficacy is difficult to assess especially when trials compare active treatments without any placebo/control group. In this study, we systematically reviewed short-term efficacies of any cCSC treatment tested in randomized controlled trials (RCT) and employed network meta-analyses to compare to non-treatment controls. We searched 11 literature databases on 20 March 2022 for RCTs of treatment of cCSC. We identified 17 RCTs including a total of 1172 eyes. Treatments included conventional laser (44 eyes), half-dose or half-fluence photodynamic therapy (PDT) (298 eyes), ranibizumab (16 eyes), antioxidants (50 eyes), mineralocorticoid receptor antagonists (187 eyes), rifampicin (91 eyes), selective retina therapy (SRT) (67 eyes) and subthreshold micropulse laser (192 eyes). Compared with controls, significant benefit on complete subretinal fluid resolution was only obtained from half-dose or half-fluence PDT (OR: 20.6; 95% CI: 6.3-66.7; p < 0.0001) and conventional laser (OR: 36.4; 95% CI: 2.0-655.7; p = 0.015), and at an order of magnitude lower degree from SRT (OR: 3.4; 95% CI: 1.7-6.8; p = 0.00075). Compared with controls and after sensitivity analyses, significant benefit in the change in best-corrected visual acuity was only obtained by half-dose/-fluence PDT (-0.13 logMAR; 95% CI: -0.20 to -0.06 logMAR; p = 0.00021). In conclusion, three treatment options provide significant improvement over no treatment: half-dose/-fluence PDT, conventional laser and to a much lesser degree SRT. Considering that conventional laser can only be applied for extrafoveal leaks, and the long-term data available for PDT-based treatments finding persisting treatment results, half-dose or half-fluence PDT is the only viable treatment option for patients with cCSC. Shortage issues with verteporfin should not lead to employment of ineffective treatment modalities, as they put patients at unnecessary risk of adverse events.

Factors Predicting Response to Selective Retina Therapy in Patients with Chronic Central Serous Chorioretinopathy

This retrospective study aimed to assess the safety and efficacy of selective retina therapy (SRT) with real-time feedback-controlled dosimetry (RFD) for chronic central serous chorioretinopathy (CSC) and to evaluate factors predictive of treatment response. We included 137 eyes of 135 patients with chronic CSC. SRT was performed to cover each of the leakage areas on fundus fluorescein angiography. Changes in mean best-corrected visual acuity (BCVA), central macular thickness (CMT), and subretinal fluid (SRF) height were evaluated at baseline and at 3 and 6 months after treatment. Complete SRF resolution was observed in 52.6% (72/137 eyes) and 90.5% (124/137 eyes) at 3 and 6 months, respectively. Mean BCVA (logMAR) significantly improved from 0.41 ± 0.31 at baseline to 0.33 ± 0.31 at month 6 (p < 0.001). Mean CMT significantly decreased from 347.67 ± 97.38 μm at baseline to 173.42 ± 30.95 μm at month 6 (p < 0.001). Mean SRF height significantly decreased from 187.85 ± 97.56 µm at baseline to 8.60 ± 31.29 µm after 6 months (p < 0.001). Baseline SRF height was a significant predictive factor for retreatment requirement (p = 0.008). In conclusion, SRT showed favorable anatomical outcomes in patients with chronic CSC. A higher baseline SRF height was a risk factor for retreatment.