Clinical Factors Related to Loculation of Fluid in 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.

Pigment Epithelial Detachment and Leak Point Locations in Central Serous Chorioretinopathy

PURPOSE

To examine the associations between the vortex vein characteristics and locations of the pigment epithelial detachment (PED) and leak point in patients with central serous chorioretinopathy (CSC).

DESIGN

Observational case series.

METHODS

We evaluated 116 eyes of 104 patients with CSC. The PED and leak point locations were superimposed over the choroidal en face images using widefield swept-source optical coherence tomography and fluorescein angiography. We defined the draining areas of the superior and inferior vortex veins and analyzed their associations with the PED and leak point locations.

RESULTS

One of the 116 eyes with a unique irrigation pattern dominated by the nasal vortex vein was excluded from the analysis. Sixty-nine (60%) of the remaining 115 eyes exhibited asymmetry between the superior and inferior vortex veins. PEDs and leak points were in the vortex vein draining area with greater dilation in 66 (96%) of 69 eyes with asymmetry, and none (0%) were in the opposite areas. Both the PEDs and leak points showed significant differences in their distributions (P < .001, respectively). Additionally, 74% of PEDs and 84% of leak points were located upstream of the vortex vein draining areas, whose frequency was significantly higher compared to other areas (P < .001, respectively).

CONCLUSION

PED and leak point spatial distributions corresponded with the most terminal part of the dilated vortex veins, suggesting that blood flow disturbances, such as stasis within the affected vortex veins, may be essential in the pathogenesis of CSC.

Scleral Thickness in Simple Versus Complex Central Serous Chorioretinopathy

PURPOSE

To evaluate the association between scleral thickness and a newly developed multimodal imaging-based classification of central serous chorioretinopathy (CSC).

DESIGN

Retrospective, cross-sectional study.

METHODS

This study included 217 eyes of 217 patients classified as simple or complex CSC based on the established protocols. Clinical and anatomical factors were compared between the 2 types. The scleral thickness was measured at 4 locations using anterior-segment optical coherence tomography.

RESULTS

Of the 217 eyes, 167 were classified as simple CSC and 50 as complex CSC. The complex CSC group showed older age (P = .011), higher male ratio (P = .001), more bilateral involvement (P < .001), poorer visual acuity (P < .001), greater subfoveal choroidal thickness (P = .025), and higher frequency of loculation of fluid (P < .001) and ciliochoroidal effusion (P < .001) than the simple CSC group. The complex CSC group had significantly greater scleral thicknesses in the superior, temporal, inferior, and nasal directions (all P < .001) than the simple CSC group. Multivariable analysis revealed that older age (odds ratio [OR] 1.054, 95% confidence interval [CI] 1.013-1.097, P < .001), male sex (OR 10.445, 95% CI 1.151-94.778, P < .001), bilateral involvement (OR 7.641, 95% CI 3.316-17.607, P < .001), and the mean value of scleral thicknesses in 4 directions (OR 1.022, 95% CI 1.012-1.032, P < .001) were significantly associated with the complex CSC.

CONCLUSIONS

Older age, male sex, bilateral involvement, and thick sclera were associated with the complex CSC. Scleral thickness seemed to determine the clinical manifestations of CSC.

Widefield choroidal vasculature associated with future condition of subretinal fluid in central serous chorioretinopathy

Purpose

To examine choroidal angiographic features in the posterior pole associated with resolution or persistency of subretinal fluid (SRF) in eyes with central serous chorioretinopathy (CSC).

Design

Observational case series.

Methods

Twenty-nine patients with treatment-naïve CSC were divided into two groups based on the presence or absence of SRF 3 months after the initial visit (month 3) without any treatment. Using enhanced depth imaging of widefield swept-source optical coherence tomography, the choroidal thickness (CT), vessel density (VD), and vessel diameter index (VDI) in the superotemporal and inferotemporal subfields on the temporal side of the 18-mm circle from the disc were measured at the initial visit. We calculated the vertical difference in CT and other choroidal angiographic parameters and evaluated their association with the SRF condition at 3 months.

Results

The SRF-resolved and SRF-persistent groups included 10 and 19 patients, respectively. At the initial visit, sex, age, axial length, symptom duration, the logarithm of the minimum angle of resolution visual acuity, and foveal thickness were not significantly different between the two groups. The SRF status at month 3 was not associated with the vertical difference in CT and choroidal VD (P = .614, .065, respectively). However, the vertical difference in choroidal VDI was positively associated with the future presence of SRF (P = .017).

Conclusions

Vertically asymmetric dilation of choroidal vessels in the posterior pole may be a vasculature feature associated with SRF from CSC and may be a good predictor of future SRF status.

Extensive reduction in choroidal thickness after photodynamic therapy in eyes with central serous chorioretinopathy

We examined the effect of reduced fluence (rf)-photodynamic therapy (PDT) of the macular area on the wide-field choroidal thickness in 20 eyes with central serous chorioretinopathy (CSC) and 20 age- and sex-matched control eyes. The choroidal thickness at the posterior pole was measured before and after rf-PDT, using a grid with inner and outer rings, each divided into superotemporal, inferotemporal, superonasal, and inferonasal quadrants, respectively, making up a total of nine subfields including the central 3 mm ring. Before treatment, all eyes showed wide-field choroidal thickening from the dilated vortex vein ampulla to the fovea, along the course of the vein. After rf-PDT of the macular area, the choroidal thickness significantly decreased, not only in the irradiated macular area but also outside the arcade vessels in all quadrants (p < 0.001 for all inner subfields; p = 0.035 and p = 0.024 for the outer superonasal and inferonasal subfields, respectively; p < 0.001 and p = 0.004 for the outer superotemporal and inferotemporal subfields, respectively). For control eyes, the choroidal thickness did not differ between the initial visit and follow-up 1.2 ± 0.7 months after the initial visit (p > 0.05 for all subfields). These findings provide new insights into the pathogenesis of CSC and explain the reasons for the effectiveness of rf-PDT for this condition.

Relationship Between Scleral Thickness and Choroidal Structure in Central Serous Chorioretinopathy

Purpose

Central serous chorioretinopathy (CSC) is a retinal disorder characterized by serous retinal detachment with or without pigment epithelial detachment in the posterior pole of the eye. We aimed to elucidate the relationship between scleral thickness and choroidal structure in CSC eyes.

Methods

This single-center retrospective study included 111 eyes of 111 CSC patients. Using swept-source optical coherence tomography, the horizontal cross-sectional images of the posterior choroid were converted to binary images by semiautomated software. The luminal and stromal areas of the choroid were measured, and the luminal/stromal (L/S) ratios of the whole choroid (WC), inner choroid, and outer choroid (OC) at 1500 µm, 3000 µm, and 7500 µm ranges centered on the fovea were calculated. Correlations of L/S ratio and age, spherical equivalent, axial length, subfoveal choroidal thickness (SCT), and scleral thickness were determined. Scleral thickness was measured vertically, 6 mm posterior to the scleral spur in four directions.

Results

SCT and mean scleral thickness were significantly positively correlated with the L/S ratio in all ranges of WC and OC. Multiple regression analysis found that SCT and mean scleral thickness were significantly correlated with the L/S ratio, and the strength of correlation of mean scleral thickness (WC: 0.386, P < 0.001; OC: 0.391, P < 0.001) was greater than that of SCT (WC: 0.368, P < 0.001; OC: 0.383, P < 0.001) in 7500 µm range.

Conclusions

Thick sclera appeared to play a role in an increase in the luminal component of the posterior choroid in CSC eyes.

Choroidal morphologic features in central serous chorioretinopathy using ultra-widefield optical coherence tomography

PURPOSE

To analyze the choroidal morphological changes in central serous chorioretinopathy (CSC) using ultra-widefield (UWF)-optical coherence tomography (OCT).

METHODS

This single-center, case-control study included 65 CSC eyes (52 males; age, 55.6 ± 13.0 years) and 65 healthy eyes (50 males; age, 57.1 ± 17.9 years). UWF-OCT (viewing angle, 200°) with real-shape correction was used to create an automated choroidal thickness (CT) map. The CT map had three sub-areas: the central (0-30°), middle (30-60°), and peripheral areas (60-100°), and was divided by vertical and horizontal lines. Differences in the CT and the CT change rate (CTCR) from the central to peripheral areas were examined between the CSC and control groups after adjusting for subjects' demographic and clinical factors. Furthermore, we assessed the vortex veins dilation patterns (VVDP) in the macula and examined the CT and the CTCR differences between CSC patients and controls for each VVDP.

RESULTS

CSC patients had greater CT than those of the controls in all sectors (CSC vs. controls, the peripheral area: supratemporal 284.4 ± 71.2 μm vs. 220.4 ± 71.2 μm, infratemporal 263.3 ± 69.2 μm vs. 195.3 ± 52.3 μm, supranasal 251.9 ± 70.3 μm vs. 189.5 ± 58.1 μm, infranasal 193.6 ± 71.2 μm vs. 146.3 ± 48.9 μm, P < 0.0001 for all sectors). The CTCR was apparently larger in CSC eyes than controls only for the upper-dominant type of VVDP (CSC patients vs. controls, supratemporal 32.1 ± 9.9% vs. 4.6 ± 23.1%, infratemporal 44.0 ± 11.2% vs. 25.6 ± 16.8%, supranasal 42.6 ± 9.8% vs. 22.2 ± 19.4%, infranasal 57.6 ± 41.2% vs. 41.2 ± 13.9%, P < 0.0001 for all sectors).

CONCLUSIONS

CSC has a thicker choroid, even in the peripheral areas, and the macular choroidal thickening was more severe in the upper-dominant type of VVDP. VVDP may affect the location of excessive fluid.

Widefield Choroidal Thickness of Eyes with Central Serous Chorioretinopathy Examined by Swept-Source OCT

PURPOSE

To examine widefield (WF) changes in the choroidal thickness of eyes with central serous chorioretinopathy (CSC).

DESIGN

An observational study.

PARTICIPANTS

Twenty-two patients (20 men and 2 women) with treatment-naïve unilateral CSC and 28 normal eyes of 28 age-matched, healthy participants (21 men and 7 women).

METHODS

We performed enhanced depth imaging of swept-source (SS) OCT with a viewing angle of vertical 20 mm × horizontal 23 mm. Moreover, we developed a grid consisting of 9 subfields, with diameters of 3, 9, and 18 mm; the inner and outer rings were enclosed by circles with diameters of 3 and 9 mm and 9 and 18 mm, respectively, which were divided into 4 subfields-superotemporal, inferotemporal, superonasal, and inferonasal.

MAIN OUTCOME MEASURES

Widefield changes in choroidal thickness.

RESULTS

The mean duration from the presumed onset of CSC was 6.8 ± 3.1 months during the examination. Compared with that in normal eyes, the choroidal thickness in eyes of patients with CSC was significantly greater in all subfields (P < 0.020 for fellow eyes; P < 0.001 for eyes with CSC). Compared with that in fellow eyes, the choroidal thicknesses in eyes of patients with CSC were significantly greater, except for the outer superotemporal and inferonasal subfields (P < 0.001 for all inner subfields; P < 0.001 for the outer superonasal and inferotemporal subfields). In areas with dilated vortex veins, choroidal thickening was observed from the vicinity of the vortex vein ampulla to the macula along the course of the veins. Choroidal thickening on the dominant side was significantly greater than that on the nondominant side (P = 0.015 for the nasal subfield of the inner ring; P = 0.003 and P < 0.001 for the temporal subfields of the inner and outer rings, respectively).

CONCLUSIONS

Enhanced depth imaging of SS-OCT facilitated the analysis of WF changes in choroidal thickness in both healthy patients and patients with CSC. The local factors of the affected vortex vein and systemic risk factors may be involved in the pathogenesis of CSC.

Hydrodynamic Analysis of the Clinical Findings in Pachychoroid-Spectrum Diseases

We wish to demonstrate that theorems of fluid dynamics may be employed to hydrodynamically analyze the clinical presentations seen within the pachychoroid-spectrum diseases (PSD). Methods: We employed both the Equation of Continuity Q = A · V in which Q represents blood flow volume, A the sectional area of a vessel, and V blood flow velocity as well as Bernoulli’s Principle 1/2 V² + P/ρ = constant where V represents blood flow velocity, P static blood pressure and ρ blood density. The Equation of Continuity states that a decrease in flow volume occurs simultaneously with a decrease in the flow velocity and/or sectional area, and vice versa. Bernoulli’s Principle states that a decrease in the velocity of a fluid occurs simultaneously with an increase in static pressure, and vice versa. Results: Hyperpermeability of the choriocapillaris, as visualized on fluorescein angiography and indocyanine green angiography (ICGA), causes a fluid exudation and, therefore, a decrease in the blood flow volume Q which elicits a simultaneous decrease in the blood flow velocity V clinically observable in filling delay into the choriocapillaris on ICGA. An increase in the static blood pressure P will simultaneously occur in venules in accord with Bernoulli’s Principle. Conclusions: A decrease in the blood flow velocity in the choriocapillaris due to its hyperpermeability will hydrodynamically elicit an increase in the blood pressure in venules. This blood pressure rise may expand Sattler and Haller veins, forming pachyveins. The primary lesion of PSD can be in pigment epithelium and choriocapillaris.

CILIOCHOROIDAL EFFUSION IN CENTRAL SEROUS CHORIORETINOPATHY

PURPOSE

To investigate the prevalence of ciliochoroidal effusion (CE) in central serous chorioretinopathy (CSC) using anterior-segment optical coherence tomography and its association with the clinical features of CSC.

METHODS

Overall, 164 eyes of 164 patients with CSC and 51 eyes of 51 age- and sex-matched normal control participants were retrospectively examined. Anterior-segment optical coherence tomography was used to assess patients with CSC and control subjects for CE and scleral thickness. Central serous chorioretinopathy eyes were divided into two groups: eyes with CE (CE group) and eyes without CE (non-CE group). Scleral thickness was measured at the point that was 6 mm posterior to the scleral spur in four directions.

RESULTS

Among the 164 eyes with CSC, 32 eyes (19.5%) displayed CE, and this proportion was significantly higher than that in control subjects (2.0%) (P = 0.001). Scleral thickness was significantly greater in the CE group compared with the non-CE group at all four directions (P < 0.05 for all). Multivariable analysis revealed that the mean scleral thickness (odds ratio: 1.01; 95% confidence interval: 1.00-1.02; P = 0.007) was significantly associated with the incidence of CE.

CONCLUSION

Central serous chorioretinopathy may accompany fluid accumulation in the anterior segment more frequently than previously expected in association with thick sclera.

Regional Scleral Thickness as a Risk Factor for Central Serous Chorioretinopathy

PURPOSE

To evaluate regional sclera thicknesses as possible risk factors for central serous chorioretinopathy (CSC).

METHODS

Patients with CSC and controls were evaluated with contact B-scan ultrasonography using a 20 Mhz concentric phased array ultrasound unit and enhanced depth imaging optical coherence tomography to measure the scleral thickness at the equator and posterior pole. The resultant data were evaluated using univariate analysis and generalized estimating equations.

RESULTS

There were 40 patients with CSC with a mean age of 58 years and 23 controls with a mean age of 60.7 years (P=.31). The mean subfoveal scleral thicknesses were 1.3 mm in the CSC group an 0.86 mm in the control group (P<.001). The mean equatorial scleral thickness was 0.61mm in the CSC group and 0.42 mm in the control group (P<.001). Using generalized estimating equations, the equatorial scleral thickness (P=.001), posterior scleral thickness (P <.001) and subfoveal choroidal thickness (p=.032) were independent predictors of CSC. Once these variables were entered into the equation, neither sex nor age were significant predictors. Generalized estimating equation analysis showed that equatorial, but not posterior, scleral thickness was a significant predictor of subfoveal choroidal thickness.

CONCLUSIONS

Scleral thicknesses of both the posterior and equatorial portions of the eye were found to be significant predictors of CSC, consistent with what was proposed in the theory venous overload choroidopathy. Direct measurement by high resolution ultrasonography provides independent information about specific regions of the sclera and also avoids making speculative assumptions derived from anterior segment measurements.