A pilot prospective study of 577-nm yellow subthreshold micropulse laser treatment with two different power settings for acute central serous chorioretinopathy

A randomized non-inferiority trial of 577nm subthreshold micropulse laser versus half-dose photodynamic therapy for acute central serous chorioretinopathy

PURPOSE

To compare the effectiveness of 577nm subthreshold micropulse laser (SML) with half-dose photodynamic therapy (Hd-PDT) for acute central serous chorioretinopathy (CSC).

METHOD

A non-inferiority clinical trial was performed with a non-inferiority margin of eight letters. Sixty-eight eyes of 68 patients with acute CSC were randomized to the Hd-PDT group or 577 nm SML group. Best-corrected visual acuity (BCVA ), the subretinal fluid (SRF), and the central foveal thickness (CFT) were evaluated at 6 months.

RESULTS

The visual acuity significantly improved from 70.38 ± 10.37 at baseline to 83.24 ± 3.03 at 6 months after treatment in the SML group (P < 0.001), from 71.09 ± 10.50 to 84.35 ± 2.09 in the PDT group (P < 0.001). SML was non-inferior to the PDT (mean difference: -0.41, 95% CI: -5.51 - 4.68, P = 0.0021). At the endpoint, CFT was significantly reduced in the two groups, but no statistical difference (P = 0.7694). The complete resolution of SRF reached 82.35% (28/34) in the SML group and 91.18% (31/34) in the PDT group, respectively,but no statistical difference (P = 0.3724).

CONCLUSIONS

SML was non-inferiority to half-dose PDT in improving the visual acuity for CSC, and it is a viable alternative, especially when the verteporfin in PDT is unavailable.

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.

Half-dose photodynamic therapy versus 577 nm subthreshold pulse laser therapy in treatment-naive patients with central serous chorioretinopathy

BACKGROUND

To compare real-life anatomical and functional outcomes of half-dose photodynamic therapy (HD-PDT) and 577 nm subthreshold pulse laser therapy (SPL) in treatment-naïve patients with central serous chorioretinopathy (CSC).

METHODS

We retrospectively reviewed consecutive treatment-naïve CSC patients with non-resolving subretinal fluid (SRF) for more than 2 months who received either HD-PDT or SPL treatment. One repetition of the same treatment was allowed in patients with persistent SRF after first treatment. Functional and anatomical outcomes were assessed after first treatment and at final visit.

RESULTS

We included 95 patients (HD-PDT group, n = 49; SPL group, n = 46). Complete resolution of SRF after a single treatment was observed in 42.9% of HD-PDT-treated patients (n = 21; median time to resolution 7.1 weeks) and in 41.3% of SPL-treated patients (n = 19; median time to resolution 7.0 weeks). In the HD-PDT-group, 44.9% of patients (n = 22) and in the SPL-group, 43.5% (n = 20) of patients, received a second treatment due to persistent SRF, while 12.2% (n = 6) and 15.2% (n = 7), respectively, opted against a second treatment despite persistent SRF. After the final treatment, complete SRF resolution was observed in 61.2% of all HD-PDT-treated patients (n = 30; median time to resolution 8.8 weeks) and 60.9% of all SPL-treated patients (n = 28; median time to resolution 13.7 weeks, p = 0.876). In the final visit, both groups showed significant improvement of BCVA in comparison to baseline (p < 0.001 for all). The change in BCVA from baseline to final visit was similar for the two groups (HD-PDT, median BCVA change 0.10 logMAR (IQR: 0.0-0.2); in SPL group, median BCVA change 0.10 logMAR (IQR: 0.0-0.2), P = 0.344). The CSC subclassification (simple versus complex) had no influence on the anatomical or functional outcome.

CONCLUSIONS

High-density 577 nm SPL resulted in as good anatomical and functional treatment as HD-PDT and may thus represent a treatment alternative to HD-PDT in CSC.

Yellow Subthreshold Micropulse Laser in Retinal Diseases: An In-Depth Analysis and Review of the Literature

Yellow subthreshold micropulse laser (YSML) is a retinal laser capable of inducing a biologic response without causing thermal damage to the targeted tissue. The 577-nm YSML is delivered to the retina abiding by different protocols in which wavelength, power, duration, spot size and number of spots can be properly set to achieve the most effective and safe treatment response in various chorioretinal disorders. The ultrashort trains of power modulate the activation of the retinal pigment epithelium cells and intraretinal cells, such as Müller cells, causing no visible retinal scars. Subthreshold energy delivered by YSML stimulates the production of the heat-shock proteins, highly conserved molecules that protect cells against any sort of stress by blocking apoptotic and inflammatory pathways that cause cell damage. YSML treatment allows resorption of the subretinal fluid in central serous chorioretinopathy and intraretinal fluid in various conditions including diabetic macular edema, postoperative cystoid macular edema and other miscellaneous conditions. YSML also seems to modulate the development and progression of reticular pseudodrusen in dry age-related macular degeneration. The aim of this review is to discuss and summarize the safety and efficacy of YSML treatment in retinal diseases.

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

Purpose. The study aimed to compare the efficacy and safety outcomes of a subthreshold micropulse treatment laser (SMTL) versus half-dose photodynamic therapy (PDT) for treatment of chronic central serous chorioretinopathy (cCSC) with parafoveal or subfoveal leakage to persistent subretinal fluid. Methods. One hundred and forty-eight patients (148 eyes) with persistent cCSC were enrolled in this retrospective study and treated with SMTL or half-dose PDT. All patients were diagnosed according to clinical characteristics and findings on multimodal imaging. The medical records including patients with a minimum follow-up period of 3 months were reviewed. The patients were divided into two groups according to the application of the SMTL or PDT. The group of the SMTL or PDT was also divided into two subgroups according to parafoveal or subfoveal leakage. The primary outcomes included best-corrected visual acuity (BCVA) and central retinal thickness (CRT) before and 1, 2, and 3 months after treatment. The repeat treatment and resolution of subretinal fluid were also collected. Results. Seventy-nine patients (79 eyes) treated with half-dose PDT and 69 Patients (69 eyes) treated with the STML were included. The mean age was 44.20 ± 7.42 years and 80% were male. No significant difference in age, gender, baseline logMAR BCVA or CRT between the half-dose PDT group and the SMTL group ( $P=0.201$ ; 0.051) can be defined. The BCVA of the SMTL group improved at 1, 2, and 3 months after treatment, while that of the half-dose PDT group improved like the SMTL group. There were no significant differences between the SMTL and the PDT group at 1, 2, and 3 months ( $P=0.723$ ; 0.139; 0.896). The CRT for the SMTL group decreased at 1, 2, and 3 months after treatment, while that of the half-dose PDT group changed like the SMTL group. However, there were significant differences between the SMTL group and the PDT group at 1and 3 months ( $P=0.010$ ; 0.009). 13/69 (18.84%) and 9/79 (11.39%) patients underwent treatment at least twice in the SMTL and half-dose PDT group, respectively, and achieved resolution of SRF after treatment. The results of subgroups analysis showed no significant differences between the logMAR BCVA of the SMTL and PDT group which were divided into parafoveal and subfoveal leakage groups after treatment, but significant difference in CRT between subgroups can be found after treatment at 1and 3 months ( $P=0.003$ ; 0.04). Conclusions. The SMTL can be an effective candidate for the treatment of persistent cCSC where leakage occurred at parafoveal or subfoveal and improvement of logMAR BCVA, but half-dose PDT has been more effective for resolution of SRF.

Short-term comparison between navigated subthreshold microsecond pulse laser and oral eplerenone for chronic central serous chorioretinopathy

To compare the anatomical/functional changes after navigated subthreshold pulse laser (SML) and oral eplerenone therapy for chronic central serous chorioretinopathy (cCSC). A total of 36 eyes of 36 patients suffering from cCSC treated with navigated SML (Navilas® 577s; OD-OS GmbH, near Berlin, Germany) (18 eyes, SML group) and oral eplerenone (18 eyes, eplerenone group) were enrolled in this retrospective study. Main outcome measures during a 3-month follow up period included changes of best corrected visual acuity (BCVA), central macular thickness (CMT), foveal subretinal fluid thickness (FSRFT), and subfoveal choroidal thickness (SFCT). At baseline average duration of symptoms was 6.8 ± 0.6 months in SML group and 6.4 ± 0.9 months in eplerenone group (p = 0.127). Mean BCVA, CMT and FSRFT changed significantly over time (p < 0.001). From baseline to 90 days the BCVA improved from 0.3 ± 0.1 to 0.1 ± 0.1 logMAR in SML group and from 0.3 ± 0. to 0.2 ± 0.1 logMAR in eplerenone group, CMT reduced from 357.1 ± 104.3 to 210.6 ± 46.7 μm and from 428.7 ± 107.7 to 332.5 ± 27.5 μm in SML group and eplerenone group respectively, FSRFT reduced from 144.4 ± 108.2 to 22.6 ± 37.2 μm and from 217.1 ± 105.9 to 54.4 ± 86.2 μm in SML group and eplerenone group. 55.6% of patients in SML group and 66.7% in eplerenone group showed a complete resolution of FSRFT during follow up. The interaction between group and time was statistically significant with greater absolute variation for CMT and FSRFT in SML group compared to eplerenone group (p < 0.001 and p = 0.043). SFCT did not change significantly during follow up (p = 0.083) for both groups. Both navigated SML and oral eplerenone were effective treatments showing recovery of retinal morphology and related visual acuity improvement in cCSC.

Subthreshold micropulse laser photocoagulation versus half-dose photodynamic therapy for acute central serous chorioretinopathy

PURPOSE

To compare the efficacy and safety of subthreshold micropulse (STMP) laser photocoagulation and half-dose photodynamic therapy (PDT) in the treatment of acute central serous chorioretinopathy (CSC).

METHODS

A total of 39 acute CSC patients were included. 18 patients were treated with STMP laser and 21 patients were treated with half-dose PDT. The main outcome measures were best-corrected visual acuity (BCVA) according to Early Treatment Diabetic Retinopathy Study (ETDRS) chart, the proportion of eyes with complete resolution of subretinal fluid, the number of treatments, and the retinal sensitivity by microperimetry during the 12-month study period.

RESULTS

The mean number of treatments during the 12-month period was 1.6 in STMP group and 1.3 in half-dose PDT group, respectively (P = 0.174). The proportion of eyes with complete resolution of subretinal fluid was 83.3% in STMP group compared with 90.5% in half-dose PDT group at 12-month (P = 0.647). The mean BCVA at 12-month after treatment was 75.28 ± 12.58 for STMP group and 76.62 ± 11.57 for half-dose PDT group, respectively (P = 0.731). No statistically significant difference was found in the mean retinal sensitivity between the two groups during the 12 months follow-up (P = 0.701 at 3 months; P = 0.725 at 6 months; P = 0.695 at 12 months).

CONCLUSIONS

Subthreshold micropulse Laser Photocoagulation is as effective as half-dose PDT for acute CSC, while minimizing the damage effect on retinal.

577 nm subthreshold micropulse laser treatment for acute central serous chorioretinopathy: a comparative study

Background

To assess the efficacy of 577 nm subthreshold micropulse laser (SML) treatment for acute central serous chorioretinopathy (CSC).

Methods

This retrospective comparative case-series included 34 eyes of 34 patients with acute CSC who received either 577 nm SML treatment (SML group, n = 16 eyes) or were only monitored (observation group, n = 18 eyes). Acute CSC was defined as disease course < 3 months. Eyes with any history of treatment in the past were excluded. Data were collected over a period of 6 months. The best corrected visual acuity (BCVA), central macular thickness (CMT), and subfoveal choroidal thickness (SFCT) were observed.

Results

SML group showed significantly greater improvement in the BCVA (logMAR) compared to observation group at 1 month (0.20 ± 0.10 vs 0.30 ± 0.12, P < 0.01), 3 months (0.13 ± 0.06 vs 0.21 ± 0.06, P < 0.01) and 6 months (0.01 ± 0.06 vs 0.09 ± 0.66, P < 0.01). The CMT reduction was significantly greater in the SML group at 1 month (337.19 ± 62.96 µm vs 395.11 ± 91.30 µm, P < 0.05), 3 months (312.94 ± 49.50 µm vs 364.50 ± 70.30 µm, P < 0.05) and 6 months (291.38 ± 26.46 µm vs 348.56 ± 54.65 µm, P < 0.05). In the SML group, the SFCT did not show a significant decrease at 1 month (468.88 ± 42.19 µm, P > 0.05) but showed a significant reduction at 3 months (451.75 ± 39.36 µm, P < 0.05) and 6 months (450.50 ± 34.24 µm, P < 0.05) from baseline (489.94 ± 45.86 µm). In the observation group, there was no significant change in SFCF during follow-up. No adverse events occurred in the SML group.

Conclusions

Although some patients with acute CSC show spontaneous healing, timely intervention with 577 nm SML can shorten the disease course, improve visual acuity, and reduce the risk of chronic transformation without adverse events.

Predicting Post-Therapeutic Visual Acuity and OCT Images in Patients With Central Serous Chorioretinopathy by Artificial Intelligence

To predict visual acuity (VA) and post-therapeutic optical coherence tomography (OCT) images 1, 3, and 6 months after laser treatment in patients with central serous chorioretinopathy (CSC) by artificial intelligence (AI). Real-world clinical and imaging data were collected at Zhongshan Ophthalmic Center (ZOC) and Xiamen Eye Center (XEC). The data obtained from ZOC (416 eyes of 401 patients) were used as the training set; the data obtained from XEC (64 eyes of 60 patients) were used as the test set. Six different machine learning algorithms and a blending algorithm were used to predict VA, and a pix2pixHD method was adopted to predict post-therapeutic OCT images in patients after laser treatment. The data for VA predictions included clinical features obtained from electronic medical records (20 features) and measured features obtained from fundus fluorescein angiography, indocyanine green angiography, and OCT (145 features). The data for OCT predictions included 480 pairs of pre- and post-therapeutic OCT images. The VA and OCT images predicted by AI were compared with the ground truth. In the VA predictions of XEC dataset, the mean absolute errors (MAEs) were 0.074–0.098 logMAR (within four to five letters), and the root mean square errors were 0.096–0.127 logMAR (within five to seven letters) for the 1-, 3-, and 6-month predictions, respectively; in the post-therapeutic OCT predictions, only about 5.15% (5 of 97) of synthetic OCT images could be accurately identified as synthetic images. The MAEs of central macular thickness of synthetic OCT images were 30.15 ± 13.28 μm and 22.46 ± 9.71 μm for the 1- and 3-month predictions, respectively. This is the first study to apply AI to predict VA and post-therapeutic OCT of patients with CSC. This work establishes a reliable method of predicting prognosis 6 months in advance; the application of AI has the potential to help reduce patient anxiety and serve as a reference for ophthalmologists when choosing optimal laser treatments.

Factors affecting the response to subthreshold micropulse laser therapy used in center-involved diabetic macular edema

The purpose of this study was to investigate the effect of the status of retinal pigment epithelium (RPE) and HbA1c levels on the efficacy of the subthreshold micropulse laser (SMPL) in the treatment of center-involving diabetic macular edema (DME). A total of 20 eyes of 20 patients (mean age 57.9 ± 9.7 years) who were diagnosed with center-involving DME and treated with SMPL for refusing intravitreal injection and 20 eyes of 20 age- and sex-matched healthy participants were enrolled. All patients were followed up in the 1st and 3rd months after SMPL. For measurement of RPE area central 1000 microns, macular EDI-OCT scans were binarized by using the public domain software ImageJ, with a semi-automated technique. There was a significant increase in BCVA values and a significant decrease in CMT values during follow-up. The area of RPE before SMPL was significantly thinner in the patient group (p: 0.004). When the areas of RPE before and 3 months after SMPL were compared, no significant change was observed (p: 0.437). When the relationship between pre-treatment area of RPE and HbA1c was examined, an inverse correlation was observed (p: 0.018). The patients were evaluated by dividing them into 2 groups as 2nd session SMPL required and not required, and the area of RPE was smaller in the group requiring 2nd session SMPL (p: 0.030). The status of central RPE may be a determining factor on the response to treatment. Additionally, HbA1c levels may have an impact on treatment efficacy.

Multifocal electroretinography-assisted anatomical and functional evaluation of subthreshold green laser in acute central serous chorioretinopathy

Purpose:

To compare observation versus subthreshold green laser (STL) in acute central serous chorioretinopathy (CSC) in terms of anatomical and functional outcomes.

Methods:

Prospective randomized interventional study. 30 eyes with the first episode of acute CSC underwent complete ophthalmologic examination, measurement of best-corrected Snellen visual acuity (BCVA), contrast sensitivity (CS), fundus fluorescein angiography (FFA), spectral-domain optical coherence tomography (SD-OCT), and multifocal electroretinography (mfERG) at baseline. Patients were randomized equally to group A (observation) or group B (STL using 532 nm wavelength applied to the leakage point). Outcome measures included BCVA, CS, central foveal thickness (CFT), and mean macular thickness (MMT) on SD-OCT and P1 amplitude and implicit time (IT) on mfERG. Patients were followed up for 6 months.

Results:

Mean BCVA was comparable between the two groups on follow up; however, mean CS was significantly higher in group B at 6 months (P = 0.032). CFT was significantly lower in group B at 1 month (P = 0.001) and 3 months (P = 0.049); however, this difference was not maintained at 6 months (P = 0.265). P1 amplitude and IT in all 5 rings were comparable between the two groups at baseline. On follow up, P1 amplitude of ring 1 became significantly higher in group B at 3 months (P = 0.036) and 6 months (P = 0.022).

Conclusion:

Immediate treatment of acute CSC with STL, as compared to conservative management, leads to more rapid resolution on SD-OCT and superior functional outcomes as evidenced by CS and mfERG.

Subthreshold Micropulse Laser vs. Conventional Laser for Central Serous Chorioretinopathy: A Randomized Controlled Clinical Trial

Purpose: To investigate the effectiveness and safety of 577-nm subthreshold micropulse laser (SML) on acute central serous chorioretinopathy (CSC). Methods: One hundred and ten patients with acute CSC were randomized to receive SML or 577-nm conventional laser (CL) treatment. Optical coherence tomography and best-corrected visual acuity (BCVA) were performed before and after treatment. Results: At 3 months, the complete resolution of subretinal fluid (SRF) in 577-nm SML group (72.7%) was lower than that in CL group (89.1%) (Unadjusted RR, 0.82; P = 0.029), but it was 85.5 vs. 92.7% at 6 months (unadjusted RR, 0.92; P = 0.221). The mean LogMAR BCVA significantly improved, and the mean central foveal thickness (CFT) significantly decreased in the SML group and CL group (all P < 0.001) at 6 months. But there was no statistical difference between the two groups (all P > 0.05). In the SML group, obvious retinal pigment epithelium (RPE) damage was shown only in 3.64% at 1 month but 92.7% in the CL group (P < 0.001). Conclusions: Although 577-nm SML has a lower complete absorption of SRF compared with 577-nm CL for acute CSC at 3 months, it is similarly effective as 577-nm CL on improving retinal anatomy and function at 6 months. Importantly, 577-nm SML causes less damage to the retina.

Predicting subretinal fluid absorption with machine learning in patients with central serous chorioretinopathy

Background

Machine learning was used to predict subretinal fluid absorption (SFA) at 1, 3 and 6 months after laser treatment in patients with central serous chorioretinopathy (CSC).

Methods

The clinical and imaging data from 480 eyes of 461 patients with CSC were collected at Zhongshan Ophthalmic Center (ZOC) and Xiamen Eye Center (XEC). The data included clinical features from electronic medical records and measured features from fundus fluorescein angiography (FFA), indocyanine green angiography (ICGA), optical coherence tomography angiography (OCTA), and optical coherence tomography (OCT). A ZOC dataset was used for training and internal validation. An XEC dataset was used for external validation. Six machine learning algorithms and a blending algorithm were trained to predict SFA in patients with CSC after laser treatment. The SFA results predicted by machine learning were compared with the actual patient prognoses. Based on the initial detailed investigation, we constructed a simplified model using fewer clinical features and OCT features for convenient application.

Results

During the internal validation, random forest performed best in SFA prediction, with accuracies of 0.651±0.068, 0.753±0.065 and 0.818±0.058 at 1, 3 and 6 months, respectively. In the external validation, XGBoost performed best at SFA prediction with accuracies of 0.734, 0.727, and 0.900 at 1, 3 and 6 months, respectively. The simplified model showed a comparable level of predictive power.

Conclusions

Machine learning can achieve high accuracy in long-term SFA predictions and identify the features relevant to CSC patients’ prognoses. Our study provides an individualized reference for ophthalmologists to treat and create a follow-up schedule for CSC patients.

Efficacy of the subthreshold micropulse yellow wavelength laser photostimulation in the treatment of chronic central serous chorioretinopathy

AIM

To evaluate the efficacy and safety of subthreshold micropulse yellow laser (SMYL) in the treatment of chronic central serous chorioretinopathy (CCSC).

METHODS

The medical records of 58 eyes of 58 patients with CCSC were reviewed. A 577-nm SMYL system was used for the treatment. Fundus fluorescein angiography was used as the primary method of identifying CCSC, and resolution of subretinal fluid (SRF) evaluated by optical coherence tomography (OCT) and fundus autofluorescence. Central macular thickness (CMT), central macular volume (CMV), total macular volume (TMV), subfoveal choroidal thickness (SFCT), subretinal fluid height (SRFH), and subfoveal fluid basement diameter values were measured by spectral domain-OCT (SD-OCT) for all eyes.

RESULTS

The mean age of the patients was 42.4±9.9 (range: 20-72)y. The mean follow-up was 11.4±8.5 (range: 6-37)mo. Median BCVA at at the final follow up after treatment was statistically significant from the baseline. Complete SRF resolution was 12.1% of the eyes in the 1^st month, 67.2% of the eyes in the 3^rd month and 67.2% of the eyes in the last follow up. The initial median CMT, CMV, TMV, and SFCT values before treatment was significantly higher than 3^rd month visit values (P<0.001). In the multivariate analysis performed, age and disease duration were found to be a risk factor for persistent SRF (P=0.017, P=0.016, respectively).

CONCLUSION

SMYL treatment provides a significant anatomical and functional improvement and is effective in eliminating SRF in eyes with CCSC.

The efficacy of subthreshold micropulse yellow laser (577 nm) in chronic central serous chorioretinopathy

Central serous chorioretinopathy (CSC) is a disease characterized by a well-defined serous detachment of the neurosensory retina. Therapeutic options in chronic cases are limited, and side effects can result in a limited response. The aim of this article is to assess the efficacy of subthreshold micropulse laser therapy in patients with chronic central serous chorioretinopathy. The study included 20 eyes of 19 patients who had a history of chronic or chronic recurrent CSC and who underwent subthreshold micropulse laser therapy between January 2015 and June 2018. Twenty eyes of 19 patients with a mean age of 48.9 ± 9.40 years were included. The mean visual acuity was 0.24 ± 0.28 logMAR before laser, 0.19 ± 0.25 logMAR 3 months after laser, and 0.18 ± 0.27 logMAR after 6 months. A statistically significant difference was determined in terms of visual acuity before and after treatment (p = 0.0001). The mean central retinal thickness was 308.10 ± 95.25 μm before laser, 233.65 ± 81.17 μm 3 months after laser, and 203.88 ± 72.79 μm at 6 months. A statistically significant relationship was present between visual acuity and the duration of disease (p = 0.001), between visual acuity and the outer nuclear layer thickness (p = 0.005), and between the outer nuclear layer thickness and the duration of disease in chronic cases (p = 0.008). There was no evidence of retinal pigment epithelium or retinal damage on optical coherence tomography or fundus autofluorescence secondary to subthreshold micropulse laser therapy. Visual acuity appears to be more associated with the duration of disease and with changes in the outer nuclear layer thickness in chronic CSC. Subthreshold micropulse laser therapy seems to be effective at treating chronic CSC, while it increases success during early period of the disease before the development of permanent retinal damage.

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.