Subthreshold Continuous Wave Autofluorescence-controlled Laser Treatment of Chronic Central Serous Chorioretinopathy

Central serous chorioretinopathy: An evidence-based treatment guideline

Central serous chorioretinopathy (CSC) is a relatively common disease that causes vision loss due to macular subretinal fluid leakage and it is often associated with reduced vision-related quality of life. In CSC, the leakage of subretinal fluid through defects in the retinal pigment epithelial layer's outer blood-retina barrier appears to occur secondary to choroidal abnormalities and dysfunction. The treatment of CSC is currently the subject of controversy, although recent data obtained from several large randomized controlled trials provide a wealth of new information that can be used to establish a treatment algorithm. Here, we provide a comprehensive overview of our current understanding regarding the pathogenesis of CSC, current therapeutic strategies, and an evidence-based treatment guideline for CSC. In acute CSC, treatment can often be deferred for up to 3-4 months after diagnosis; however, early treatment with either half-dose or half-fluence photodynamic therapy (PDT) with the photosensitive dye verteporfin may be beneficial in selected cases. In chronic CSC, half-dose or half-fluence PDT, which targets the abnormal choroid, should be considered the preferred treatment. If PDT is unavailable, chronic CSC with focal, non-central leakage on angiography may be treated using conventional laser photocoagulation. CSC with concurrent macular neovascularization should be treated with half-dose/half-fluence PDT and/or intravitreal injections of an anti-vascular endothelial growth factor compound. Given the current shortage of verteporfin and the paucity of evidence supporting the efficacy of other treatment options, future studies-ideally, well-designed randomized controlled trials-are needed in order to evaluate new treatment options for CSC.

Central Serous Chorioretinopathy: Morphological and Functional Outcome after Subthreshold Thermal Laser Coagulation with a Frequency-Doubled Nd:YAG Continuous-Wave Laser

PURPOSE

Central serous chorioretinopathy (CSCR) presents itself as a serous detachment of the central neurosensory retina (NR), which may be accompanied by focal detachment of the retinal pigment epithelium (RPE) and changes in the RPE itself. It is often self-limiting; however, if the macular region is affected, visual impairment can be serious. If spontaneous remission does not occur, data on the effectiveness of further treatment options are sparse. We therefore decided to examine the effectiveness of subthreshold laser photocoagulation (ST-LP) on best-corrected visual acuity (BCVA) and subretinal fluid (SRF) resorption. We conducted a retrospective analysis of all patients who underwent ST-LP based on the diagnosis of CSCR in a German university eye hospital from 2009 to 2014.

METHODS

The diagnosis of CSCR was based on the following criteria: detachment of the NR and possibly the RPE visible on ophthalmoscopy, evidence of SRF on optical coherence tomography (OCT), visualization of one or more source points typical for CSCR in fluorescein angiography, and exclusion of differential diagnoses. The time between the anamnestic onset of symptomatic complaints and ST-LP was determined as well as BCVA and OCT before ST-LP. ST-LP was performed as a subthreshold thermal laser coagulation with a frequency-doubled Nd:YAG continuous-wave laser. Follow-up examinations were scheduled at 4, 8, and 12 weeks after ST-LP.

RESULTS

Fifty-four eyes of 49 patients were included in the study. The median age of patients was 47 years. Eighty-nine percent of the included patients were male. Twenty percent of patients had a first manifestation of CSCR, 69% had a recurrence, and 11% had persistent SRF for >6 months. The median visual acuity rose from 0.30 at baseline (BL) to 0.10 at 4 weeks and 0.00 at 8 weeks, before dropping slightly to 0.05 at 12 weeks. Changes of visual acuity in comparison to BL were statistically significant (p < 0.05). The initial median retinal thickness of 397 μm at BL decreased to 264 μm at 4 weeks, to 236 μm at 8 weeks, and to 239 μm at 12 weeks (decreases to BL all statistically significant p < 0.05).

CONCLUSION

In our cohort, we were able to achieve substantial and significant clinical benefit through ST-LP measured by improvement in BCVA. Furthermore, we were also able to demonstrate measurable, significant morphological improvements as decreased retinal thickness and increased resorption of SRF as probable mechanisms explaining clinical improvement of CSCR with ST-LP. The advantage of ST-LP over other methods is the low risk of adverse events and its high availability. Controlled, randomized studies are necessary to confirm the data and demonstrate the effect over a longer period of time.

Efficacy of nanosecond laser treatment in central serous chorioretinopathy with and without atrophy of retinal pigment epithelium

Background

To evaluate the outcomes of subthreshold nanosecond laser treatment of chronic central serous chorioretinopathy (CSC) as a function of the severity of concomitant of retinal pigment epithelium (RPE) defects.

Methods

This retrospective study compares data from 23 CSC diagnosed eyes with only mild RPE defects (group 1), 16 CSC eyes with moderate RPE defects (group 2), and 17 CSC eyes having severe RPE defects (group 3). After subthreshold treatment with the standard Ellex 2RT™ nanosecond laser (Ellex Medical Lasers Ltd, Australia), changes in macular structure and levels of subretinal fluid (SRF) were assessed by OCT-SD, OCT-A, functional integrity of the retina was assessed by corrected distance visual acuity (CDVA) and microperimetry, each at baseline and 1, 3, 6, and 12 months after initial treatment; re-treatment took place in cases of persistent SRF pro re nata.

Results

During the 12 months observation period, group 1 and 2 mostly required on initial and one re-treatment (1.9 ± 1.0 treatments; 1.9 ± 1.3 treatments). In contrast, group 3 was subject to three to four treatments (3.7 ± 1.5 treatments). 6 to 12 months after treatment, subretinal fluid (SRF) disappeared in 100% of the eyes of group 1 and in 76.9%, and 42.9% of the eyes of group 2 and group 3, respectively. Retinal sensitivity and CDVA improved in group 1 and 2, but did not change significantly in group 3 during the 12 months period.

Conclusions

Subthreshold nanosecond laser treatment is an effective and safe method for the restoration of macular anatomy and sensitivity in acute and chronic CSC cases with only mild or moderate RPE defects. However, this laser treatment has very limited outcome in CSC eyes with more severe RPE defects.

Central serous chorioretinopathy: Towards an evidence-based treatment guideline

Central serous chorioretinopathy (CSC) is a common cause of central vision loss, primarily affecting men 20-60 years of age. To date, no consensus has been reached regarding the classification of CSC, and a wide variety of interventions have been proposed, reflecting the controversy associated with treating this disease. The recent publication of appropriately powered randomised controlled trials such as the PLACE trial, as well as large retrospective, non-randomised treatment studies regarding the treatment of CSC suggest the feasibility of a more evidence-based approach when considering treatment options. The aim of this review is to provide a comprehensive overview of the current rationale and evidence with respect to the variety of interventions available for treating CSC, including pharmacology, laser treatment, and photodynamic therapy. In addition, we describe the complexity of CSC, the challenges associated with treating CSC, and currently ongoing studies. Many treatment strategies such as photodynamic therapy using verteporfin, oral mineralocorticoid antagonists, and micropulse laser treatment have been reported as being effective. Currently, however, the available evidence suggests that half-dose (or half-fluence) photodynamic therapy should be the treatment of choice in chronic CSC, whereas observation may be the preferred approach in acute CSC. Nevertheless, exceptions can be considered based upon patient-specific characteristics.