Dilatation of Asymmetric Vortex Vein in Central Serous Chorioretinopathy

Inversion of Asymmetric Vortex Vein Dilatation in Pachychoroid Spectrum Diseases

Purpose

Intervortex venous anastomosis is widely recognized as compensating for vortex vein congestion in pachychoroid spectrum diseases. However, determining the blood flow direction within the compensated drainage route is often challenging. Herein, we investigated the morphological patterns of vortex veins in eyes showing retrograde pulsatile vortex venous flow.

Design

Retrospective observational case series.

Subjects

Six hundred eighty-nine consecutive eyes with treatment-naive central serous chorioretinopathy, pachychoroid neovasculopathy, or polypoidal choroidal vasculopathy.

Methods

We reviewed the clinical records of patients with these pachychoroid spectrum diseases. Multimodal images including indocyanine green angiography (ICGA) and en face OCT were analyzed.

Main Outcome Measures

Intervortex venous anastomosis between superotemporal and inferotemporal vortex veins and the dominant site of dilated temporal vortex veins were determined in the eyes with retrograde pulsatile vortex venous flow in the temporal vortex veins.

Results

Twenty-two eyes with retrograde pulsatile vortex venous flow in the temporal vortex veins were identified utilizing early phase ICGA videos. In 9 eyes, retrograde pulsatile flow was detected in the superotemporal vortex veins, which were connected to the inferotemporal vortex veins via intervortex venous anastomoses. Among these cases, contralateral inferotemporal vortex vein dilatation was dominant in 7 eyes (77.8%), while superotemporal and inferotemporal vortex veins were symmetrically dilated in the other 2 eyes (22.2%). On the other hand, in 13 eyes, the retrograde pulsatile flow was detected in the inferotemporal vortex veins, which were linked to the superotemporal vortex veins via intervortex venous anastomoses. In these eyes, contralateral superotemporal vortex vein dilatation was dominant in 10 eyes (76.9%). Superotemporal and inferotemporal vortex veins were symmetrically dilated in 2 eyes (15.4%), while mainly inferotemporal vortex veins were dilated in 1 eye (7.7%).

Conclusions

In pachychoroid spectrum diseases, there are cases wherein congested venous blood might drain into the contralateral vortex veins via intervortex anastomoses. Overloaded contralateral vortex veins may, as a consequence, become more dilated than the primary congested vortex veins. Inversion of asymmetric vortex vein dilatation might thereby develop in pachychoroid spectrum diseases.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

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.

Biomechanical properties measured with dynamic Scheimpflug analyzer in central serous chorioretinopathy

PURPOSE

Recent evidence suggests that venous congestion at the vortex vein significantly contributes to the development of central serous chorioretinopathy (CSCR), and sclera is observed to be thicker in affected eyes. This study aims to investigate whether eyes with CSCR exhibit stiff corneas, measured using Corneal Visualization Scheimflug Technology (Corvis ST), which may serve as an indicator of scleral stiffness.

METHODS

This retrospective case-control study comprises 52 eyes from 33 patients diagnosed with CSCR and 52 eyes from 32 normal controls without CSCR. We compared biomechanical parameters measured with Corvis ST and anterior scleral thickness measured using anterior segment swept-source optical coherence tomography between the two groups.

RESULTS

Age, sex, axial length, intraocular pressure, and central corneal thickness showed no significant differences between the two groups (p > 0.05, linear mixed model). Three biomechanical parameters-peak distance, maximum deflection amplitude, and integrated inverse radius-indicated less deformability in CSCR eyes compared to control eyes. The stress-strain index (SSI), a measure of stiffness, and anterior scleral thickness (AST) at temporal and nasal points were significantly higher in the CSCR eyes. SSI and AST were not correlated, yet both were significantly and independently associated with CSCR in a multivariate logistic regression model.

CONCLUSIONS

Eyes affected by CSCR have stiffer corneas, irrespective of thicker scleral thickness. This suggests that stiffer sclera may play a role in the pathogenesis of CSCR.

Quantitative assessment of intervortex anastomosis in central serous chorioretinopathy and fellow eyes: Does the size of anastomotic vessels matter for the diagnosis?

PURPOSE

To evaluate the frequency and size of intervortex anastomosis at the posterior pole on en-face spectral domain optical coherence tomography (SD-OCT) images in central serous chorioretinopathy (CSC) cases and their fellow eyes and its associations with choroidal morphology.

METHODS

Sixty-five treatment-naive eyes of 65 patients with CSC, 65 fellow eyes, and 55 eyes of healthy age-matched participants were included. The presence of intervortex anastomosis at the watershed zone and asymmetry of the choroidal vessels between the superior and inferior macula were evaluated using 6 × 6 mm en-face SD-OCT. The diameter of the widest Haller vessel and the diameter of the widest anastomotic Haller vessel passing through the watershed zone were measured on en-face SD-OCT images. The choroidal vascularity index (CVI) was assessed using ImageJ software.

RESULTS

Intervortex vein anastomosis on the horizontal watershed zone was detected in 75.4% diseased eyes, 61.5% in fellow eyes, and 36.4% in healthy age-matched controls (p < 0.001). The mean CVI was significantly higher in both diseased (74.3 ± 2.3%) and fellow (73.8 ± 2.2%) eyes of CSC cases than in healthy controls (72.5 ± 2.3%) (p = 0.002, p = 0.013, respectively). In the cases with intervortex vein anastomosis, the diameter of the widest anastomotic Haller vessel passing through the watershed zone was 0.40 ± 0.10 mm in diseased eyes, 0.35 ± 0.11 mm in fellow eyes, and 0.30 ± 0.09 mm in healthy age-matched controls (p = 0.001).

CONCLUSIONS

Intervortex anastomosis might be seen as a variation in normal eyes, however, its frequency and the size of anastomotic vessels are significant higher in not only CSC but also in fellow eyes.

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.

Choroidal Vascular Changes on Ultrawidefield Indocyanine Green Angiography in Central Serous Chorioretinopathy: CERTAIN Study Report 1

PURPOSE

Choroidal venous overload was recently suggested to be a pathogenetic factor in central serous chorioretinopathy (CSC). Manifestations of venous overload on ultrawidefield indocyanine green angiography (UWF ICGA) include asymmetric arterial choroidal filling (AACF), enlarged choroidal vessels ("pachyvessels"), and asymmetric venous drainage (AVD) leading to choroidal intervortex venous anastomoses (CVAs) accompanied by choroidal vascular hyperpermeability (CVH). The purpose of the current study is to assess the presence of these signs of venous overload in a large cohort of CSC patients.

DESIGN

Monocentric retrospective cohort study.

PARTICIPANTS

Consecutive CSC patients seen at a large tertiary referral center.

METHODS

For the CERTAIN study, patients underwent a standardized imaging protocol including UWF ICGA. Features of choroidal venous overload were graded for each eye individually by 2 independent graders and, in case of disagreement, by a third grader.

MAIN OUTCOME MEASURES

Presence of AAFC, pachyvessels, AVD, CVA, and CVH.

RESULTS

In total, 178 eyes of 91 patients were included in this study. Mean patient age was 47.6 (± 12.0) years and 75 patients (82%) were male. The 116 eyes (65%) that showed subretinal fluid were considered affected (bilateral disease in 29 patients). In affected eyes, AACF was present in 62 eyes (85% of gradable eyes), pachyvessels in 102 eyes (88%), AVD in 81 eyes (74%), CVA in 107 eyes (94%), and CVH in 100% of affected eyes. For fellow eyes, prevalence of pachyvessels (94%), AVD (67%), and CVA (90%) was similar to affected eyes, whereas CVH was present in 85% of fellow eyes. Intergrader agreement was excellent for CVH (94%), and 74%-82% for all other criteria. Patients with pachyvessels and AVD in 1 eye were more likely to also show the same characteristic in the fellow eye (odds ratios 22.2 and 9.9, P < 0.01).

CONCLUSIONS

Signs of venous overload are seen in the vast majority of CSC patients, both in affected and unaffected eyes. Although pachyvessels, AVD, and CVA are observed frequently, CVH was observed in all affected eyes, showed excellent intergrader reliability, and is diagnostic for CSC. This supports the concept of choroidal venous overload as a major factor in CSC pathogenesis.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Age-Related Macular Degeneration Choroidal Vascular Distribution Characteristics Based on Indocyanine Green Angiography

Purpose

The purpose of this study was to present our findings of the distribution pattern of choroidal arteries and large veins in patients with age-related macular degeneration (AMD) using indocyanine green angiography (ICGA).

Methods

A retrospective analysis was conducted on 980 patients who underwent ICGA at The Second Affiliated Hospital of Xi'an Jiaotong University from 2017 to 2023, including 240 patients with AMD. Secondary image processing was applied to the angiographic videos to obtain posterior distribution maps of choroidal arteries and large veins. Differences between different distribution patterns regarding age, gender, eye laterality, and circulation time were compared. We also conducted a comparison of choroidal vascular distribution characteristics between patients with AMD and patients with diabetic retinopathy (DR) and provided a summary of choroidal vascular distribution patterns in AMD.

Results

The filling patterns of choroidal arteries can be classified into the invisible trunk arteries type, the partially masked trunk arteries type, and the exposed trunk arteries type. The vascular topography of the large choroidal vein can be classified into the watershed type, the non-watershed type, and the unknown type, further divided into six subtypes. The distribution patterns of choroidal arteries and veins were significantly correlated with age (P < 0.001). Left eye, older age, and the exposed trunk arteries type were independent risk factors for non-watershed large choroidal vein (P < 0.05). The non-watershed type was the main characteristic of the venous phase in AMD.

Conclusions

The distribution characteristics of the arterial and venous patterns in AMD suggest atrophy of the small blood vessels in the choroid and insufficient perfusion pressure of the blood flow.

Relationship between pulsation of posterior vortex vein, choroidal thickness, and choroidal vascular hyperpermeability in polypoidal choroidal vasculopathy

PURPOSE

Posterior vortex vein pulsation on Heidelberg indocyanine green angiography (HRA-IA) video is reported to indicate the presence of congestion in these vessels. This study aimed to determine the relationship between posterior vortex vein pulsation, choroidal thickness, and choroidal vascular hyperpermeability (CVH) in polypoidal choroidal vasculopathy (PCV).

METHODS

Forty-three eyes of 43 patients who had not received previous treatment and were diagnosed with PCV using multimodal imaging were included and retrospectively investigated. On initial visit, presence or absence of pulsation in the posterior vortex vein was analysed using HRA-IA. Subfoveal choroidal thickness (SFCT) was assessed, and patients were divided into the SFCT ≥ 200 μm and < 200 μm (P and NP, respectively) groups. Presence or absence of CVH was investigated using IA in the late phase, and the associations between the three parameters were analysed.

RESULTS

Posterior vortex vein pulsation was detected in 24/43 eyes (55%). There were 27 eyes in the P group (mean SFCT, 286 ± 48 μm) and 16 eyes in the NP group (mean SFCT, 143 ± 41 μm). Pulsation was detected in 10 eyes (37%) in the P group and 14 eyes (88%) in the NP group. Incidence of pulsation was significantly higher in the NP group (P < 0.05). There were 17 (40%) patients with CVH-13 (48%) and four (25%) in the P and NP groups, respectively (P = 0.1994). There was no correlation between the presence or absence of pulsation and CVH (P = 0.1994).

CONCLUSION

Congestion of the vortex vein is potentially associated with the pathogenesis of PCV with a thin choroid.

Attenuation of irradiated choroid and its regional vortex veins in central serous chorioretinopathy after photodynamic therapy

We retrospectively studied 12 eyes of 12 patients with central serous chorioretinopathy (CSC) to investigate choroidal thickness changes following half-fluence photodynamic therapy (PDT) using widefield choroidal thickness maps obtained by optical coherence tomography (OCT). Additionally, we assessed the relationship between choroidal thickness changes and the regional vortex veins as visualized on widefield en face OCT of the choroid. Pre-treatment en face images of the choroidal vasculature were superimposed on subtracted choroidal thickness maps before and 3 months after half-fluence PDT. The choroidal thickness decreased mainly in the irradiated macular area and in the region of vortex veins which function as drainage for the macula in all eyes. Eleven eyes (91.7%) showed choroidal thinning in the nasal area which overlapped with the nasal vortex vein distribution. Moreover, in 10 (90.9%) of those eyes, we observed intervortex venous anastomosis across the vertical watershed zone. Quantitative analysis revealed that the reduction in choroidal thickness was most pronounced in the macular area. Furthermore, the choroidal thickness reduction in the area with macular drainage vortex veins was significantly greater than that in the area without such vortex veins. These results suggest that half-fluence PDT might decrease choroidal thickness due to choriocapillaris occlusion in the irradiated macula, possibly leading to diminished venous drainage from the macula to regional vortex veins. Moreover, venous blood flow through the anastomotic vessels from the macular drainage vortex veins into the nasal vortex veins might be reduced post-treatment.

SCLERAL THICKNESS IN THE FELLOW EYES OF PATIENTS WITH UNILATERAL CENTRAL SEROUS CHORIORETINOPATHY

PURPOSE

The sclera is reportedly thicker in eyes with central serous chorioretinopathy (CSC) than in healthy control eyes. We compared the scleral thicknesses of the affected and unaffected fellow eyes of patients with unilateral CSC.

METHODS

We retrospectively examined the findings of 115 patients with unilateral CSC. Comparisons of the spherical equivalent, axial length, anterior chamber depth, subfoveal choroidal thickness, scleral thickness, and presence of peripheral ciliochoroidal effusion of the affected and fellow eyes were made. Using anterior segment optical coherence tomography, scleral thickness was measured vertically, 6 mm posterior to the scleral spur in the superior, temporal, inferior, and nasal directions.

RESULTS

No significant differences in scleral thickness in all four directions, spherical equivalent, axial length, anterior chamber depth, and frequency of ciliochoroidal effusion were found between the affected and unaffected fellow eyes. The only significant difference between the affected and fellow eyes was observed in the subfoveal choroidal thickness (398.8 µ m vs. 346.6 µ m, P < 0.001).

CONCLUSION

A thickened choroid seems to have a direct effect on CSC development. By contrast, the affected and fellow eyes showed no significant difference in scleral thickness, indicating that scleral thickening may be a predisposing factor for the development of CSC.

Differences in Central and Peripheral Choroidal Thickness among the Subtypes of Age-Related Macular Degeneration in an Asian Population

Age-related macular degeneration (AMD) causes visual impairment in individuals who are >50 years of age. However, no study has investigated AMD when using ultra-wide-field swept-source optical coherence tomography (UWF SS-OCT). We aimed to evaluate central and peripheral choroidal thicknesses using UWF SS-OCT, and to compare these across the AMD subtypes. We included 75 eyes of patients with typical AMD (tAMD), 56 with polypoidal choroidal vasculopathy (PCV), 29 with pachychoroid neovasculopathy (PNV), and 12 with retinal angiomatous proliferation (RAP). To compare choroidal thicknesses in the central and peripheral choroids, we established subfields of <3 mm, <9 mm, and 9-18 mm from the fovea. PNV patients were significantly younger than those with tAMD (p = 0.01). The choroidal thicknesses of PNV were significantly greater than that of tAMD in all subfields (p < 0.01), and choroidal thickness significantly correlated with age and axial length in all subfields (p < 0.05). Even after adjusting for age and axial length, the choroidal thickness in PNV was significantly greater than that in tAMD (p < 0.05). In addition, the ratio of the posterior <9 mm to a peripheral 9-18 mm choroidal thickness in PNV was significantly greater than that in tAMD (p < 0.01). A thickened choroid in PNV was more pronounced in the posterior choroid than in the periphery.

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.

Choroidal Vein Alterations in Pachychoroid Disease With Choroidal Vascular Hyperpermeability: Evaluated by Wide-Field Indocyanine Green Angiography

Purpose

The purpose of this study was to investigate choroidal vein (ChV) morphological features in pachychoroid disease (PCD) with choroidal vascular hyperpermeability (CVH).

Methods

This retrospective study assessed subfoveal choroidal thickness (SFCT) and CVH area numbers and locations of recruited patients with PCD using multimodal images. ChV alteration patterns, including fusiform, bulbosity, sausaging, confluence, and anastomoses, as well as asymmetric ChVs, dominant ChVs, and non-dominant ChVs, were evaluated using wide-field indocyanine green angiograms.

Results

Of 68 PCD eyes from 35 patients (mean age: 46.16 ± 6.28 years, 71.4% men), 2.9% had uncomplicated pachychoroid, 32.4% had pachychoroid pigment epitheliopathy (PPE), 55.9% central serous chorioretinopathy (CSC), and 8.8% pachychoroid neovasculopathy (PNV). Mean SFCT was 468.65 ± 131.40 µm. Among 419 CVH areas, ChV fusiform, ChV bulbosity, and ChV sausaging accounted for 35.8%, 35.1%, and 29.1%, respectively; 21.2% had ChV confluence and 11.9% had ChV anastomoses. At CVH areas, 13.1% had retinal pigment epithelium (RPE) leakage. ChV fusiform is steadily declining (37.4%, 36.8%, and 22.9%, respectively), and ChV sausaging, ChV anastomoses, and ChV confluence are increased gradually in the PPE, CSC, and PNV groups (21.4%, 30.0%, and 37.1%; 11.4%, 11.1%, and 20.0%; and 19.8%, 20.9%, and 28.6%, respectively). Dominant ChVs had higher CVH area numbers than non-dominant ChVs in the PPE and CSC groups (P = 0.010, P = 0.001).

Conclusions

Different patterns of ChV alterations, including the newly identified ChV confluence, are commonly present at CVH areas in PCD. The CVH areas in PCD eyes are primarily located within the dominant ChVs. These findings provide crucial evidence for advancing our understanding of the underlying mechanisms of PCD pathogenesis.

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 macular intervortex vein anastomosis and optical coherence tomography biomarkers in chronic central serous chorioretinopathy

BACKGROUNDS

To evaluate the optical coherence tomography (OCT) biomarkers of patients with central serous chorioretinopathy (CSC) according to the presence or absence of direct anatomical relation to intervortex vein anastomosis (IVA) on indocyanine green angiography.

METHODS

We reviewed the records of 39 patients with chronic CSC. Patients were categorized in 2 groups: presence of IVA(Group A) or absence of IVA(Group B) in the macular region. Localization of IVA was categorized in 3 areas according to ETDRS grid:inner 1 mm circle (area-1), 1-3 mm middle circle (area-2) and 3-6 mm outer circle (area-3).

RESULTS

There were 31 eyes in Group A,21 eyes in Group B. Mean age of the patients was 52.5 ± 11.3years in Group A,47.2 ± 11years in Group B(p<0.001).Mean initial visual acuity (VA) was 0.38±0.38LogMAR in Group A, 0.19±0.21LogMAR in Group B(p<0.001).Mean subfoveal choroidal thickness(SFCT) was 436.3 ± 134.3µ in Group A,480.2 ± 136.6µ in Group B(p<0.001).Localization of IVA in area-1 was correlated with inner choroidal attenuation (ICA) and leakage on IVA(p = 0.011,p = 0.02). Localization of IVA in area-3 was correlated with irregular lesions on RPE(p = 0.042).Smokestack configuration,intraretinal cysts and ICA were correlated with worse initial VA(p<0.001,p = 0.001 and p = 0.04).Shaggy subtype of photoreceptor disruption was associated with better initial VA(p = 0.003).

CONCLUSIONS

We detected older age, worse initial VA and thinner SFCT in patients with chronic CSC and macular region IVA(m-IVA). Long term follow-up of patients with and without m-IVA may exhibit the difference in treatment outcomes and development of neovasculopathy.

QUANTITATIVE ANALYSIS OF CHOROIDAL MORPHOLOGY USING MULTIMODAL IMAGING IN ACUTE AND PERSISTENT CENTRAL SEROUS CHORIORETINOPATHY

PURPOSE

To analyze quantitative differences in choroidal morphology between acute and persistent central serous chorioretinopathy using multimodal images.

METHODS

Ultra-widefield indocyanine green angiography (UWICGA) and optical coherence tomography images of 72 eyes of 72 patients with acute (32 eyes) and persistent (40 eyes) central serous chorioretinopathy were collected. Choroidal thickness, area, vessel density, symmetry, and intervortex anastomosis were assessed.

RESULTS

The choroidal area on optical coherence tomography B-scan images was smaller and the choroidal vessel density on UWICGA images was lower in the persistent group ( P < 0.001 and P = 0.028, respectively). Choroidal vessel density on UWICGA showed positive correlation with that of vortex ampullae (all P ≤ 0.046). The constitution of the intervortex anastomosis and dominant vessels in the macular area showed differences between the groups ( P = 0.014 and P = 0.010, respectively), with greater inferonasal vessel participation in the anastomosis and combined superotemporal and inferotemporal vessels as dominant vessels in the persistent groups.

CONCLUSION

Acute and persistent central serous chorioretinopathy differed in subfoveal choroidal area, choroidal vessel density, and intervortex anastomosis constitution on UWICGA images. Choroidal vessel density on UWICGA images correlated with that of vortex ampullae. These findings enhance our understanding of the pathophysiology of central serous chorioretinopathy subtypes.

CENTRAL SEROUS CHORIORETINOPATHY MIMICKING IDIOPATHIC UVEAL EFFUSION SYNDROME

PURPOSE

To describe central serous chorioretinopathy cases presenting as uveal effusion syndrome, providing new insights into "pachychoroid spectrum" diseases.

METHODS

Clinical charts, color fundus photographs, fluorescein angiography, indocyanine green angiography, optical coherence tomography, ultrasound imaging, cerebral magnetic resonance imaging, and biometry of four eyes of three patients were assessed. A literature review was conducted.

RESULTS

The three patients had peripheral choroidal detachment and inferior bullous retinal detachment associated with central serous chorioretinopathy features detected using multimodal imaging, including fluorescein and indocyanine green angiography. The choroid was thick in the three patients, and uveal effusion occurred after steroid treatment in all cases. Subretinal fluid drainage and deep sclerectomy with flaps of 4 × 4 mm in both inferior quadrants were performed in three eyes of two patients with good outcomes. One patient was treated with photodynamic therapy. All three patients developed a typical leopard-spot pigmentary pattern in the fundus.

CONCLUSION

A severe presentation of highly exudative central serous chorioretinopathy may occur in rare cases with a peripheral choroidal detachment mimicking uveal effusion syndrome. These severe cases highlighted the role of choroidal thickening and hyperpermeability, choroidal vein dilation, and possible scleral thickening in both entities.

DISTINCT CHARACTERISTICS OF SIMPLE VERSUS COMPLEX CENTRAL SEROUS CHORIORETINOPATHY

PURPOSE

To compare the clinical and genetic characteristics of simple and complex central serous chorioretinopathy using central serous chorioretinopathy international group criteria.

METHODS

Patients with idiopathic central serous chorioretinopathy were included. Depending on the presence or absence of retinal pigment alterations greater than 2-disc areas in either eye, patients were classified into complex or simple types. Demographic factors and clinical findings were compared between groups. CFH variants, including rs800292 and rs1329428, were genotyped using TaqMan technology.

RESULTS

A total of 319 consecutive patients were evaluated at the initial presentation. Of them, 53 (16.6%) had the complex type. The complex type was exclusively seen in men (100% vs. 79.0%, P = 2.0 × 10 -4 ) and demonstrated a significantly higher proportion of bilateral involvement (75.5% vs. 17.7%, P = 6.2 × 10 -18 ) and descending tract(s) (83.0% vs. 0%, P = 1.2 × 10 -57 ) than the simple type. Increased choroidal thickness (425 ± 131 vs. 382 ± 110, P = 0.02) and decreased central retinal thickness (274 ± 151 vs. 337 ± 136, P = 2.9 × 10 -4 ) were observed for the complex versus simple type. The risk allele frequencies of both variants were significantly higher in the complex versus simple type (rs800292: 61.3% vs. 48.7%, P = 0.018; rs1329428: 65.1% vs. 54.3%, P = 0.04).

CONCLUSION

In this new classification system, the complex type has distinct genetic and clinical characteristics compared with the simple type.

Retinal Pigment Epithelial Abnormality and Choroidal Large Vascular Flow Imbalance Are Associated with Choriocapillaris Flow Deficits in Age-Related Macular Degeneration in Fellow Eyes

Choriocapillaris flow deficits detected on optical coherence tomography angiographs were retrospectively analyzed. In 38 age-related macular degeneration (AMD) fellow eyes, without fundus findings (26 men, 71.7 ± 1.9 years old), and 22 control eyes (11 men, 69.4 ± 1.8), the choriocapillaris flow area (CCFA) ratio and coefficient of variation (CV) of the CCFA ratio (which represented the heterogeneity of the ratio), negatively and positively correlated with age (all p < 0.01), respectively. Moreover, the respective mean values were lower (p = 0.0031) and greater (p = 0.002) in AMD fellow eyes than in the control eyes. The high-risk condition of AMD fellow eyes was defined by a CCFA ratio <58.5%, and the CV of the CCFA ratio ≥0.165 (odds ratio (OR), 5.408; 95% confidence interval (CI): 1.117-21.118, p = 0.035, after adjusting for age and sex) was related to the presence of fundus autofluorescence abnormality (OR, 16.440; 95% CI, 1.262-214.240; p = 0.033) and asymmetrically dilated choroidal large vasculature (OR, 4.176; 95% CI, 1.057-16.503; p = 0.042), after adjusting for age and sex. The presence of fundus autofluorescence abnormality indicated a retinal pigment epithelium (RPE) abnormality. The RPE volume was reduced in the latter eye group, particularly in the thinner choroidal vasculature. In addition to aging, RPE abnormality and choroidal large vascular flow imbalances were associated with exacerbated heterogeneous choriocapillaris flow deficits in AMD fellow eyes without macular neovascularization.

Pathomechanisms in central serous chorioretinopathy: A recent update

BACKGROUND

Central serous chorioretinopathy (CSCR) is a potentially blinding choroidal disease. Despite decades of research, the pathological mechanisms of CSCR are still poorly understood. In recent years, there has been a strong emphasis on choroidal dysfunction as a primary cause of CSCR.

MAIN BODY

The concept of the pachychoroid disease spectrum and pachychoroid-driven processes are central to current theories regarding the pathophysiological underpinnings of CSCR. Choroidal hyperpermeability and subsequent leakage of fluid seen in CSCR may be due to several causes. Among them are venous congestion, inflammation, mineralocorticoid receptor activation, systemic factors including hemodynamic changes, obstructive sleep apnea, phosphodiesterase inhibitor use, pregnancy, and genetic predispositions. Congestion of vortex veins that drain blood from the choroid may contribute to the dilation of Haller vessels and cause fluid leakage. Vortex veins exit the eye through the sclera; thus, increased scleral thickness has been proposed to be a factor in venous congestion. Asymmetric vortex vein drainage may similarly result in congestion of the local venous system. Vortex vein anastomoses may overload the venous system and form secondary to venous congestion. Recent studies suggest inflammation and mineralocorticoid activation may factor into the development of CSCR, though more research in these areas is called for. Systemic conditions and genetics may predispose individuals to develop CSCR.

CONCLUSIONS

By striving to understand the molecular and physiological mechanisms of this disease, we can better diagnose and treat CSCR to improve outcomes for patients.

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.

Natural Course of Pachychoroid Pigment Epitheliopathy

PURPOSE

To investigate the natural course of pachychoroid pigment epitheliopathy (PPE).

DESIGN

A retrospective cohort study.

SUBJECTS

From the Kyoto central serous chorioretinopathy (CSC) cohort consisting of 548 patients with CSC as of September 2020, we included consecutive unilateral patients with acute or chronic CSC between January 2013 and December 2016.

METHODS

All patients underwent complete ophthalmic examination, including multimodal imaging such as fundus autofluorescence, spectral-domain optical coherence tomography, and fluorescein angiography/indocyanine green angiography and/or optimal coherence tomography angiography. The fellow eyes of eyes diagnosed with CSC were screened for PPE, and their natural course was evaluated. We also evaluated the association of ARMS2 rs10490924, CFH rs800292, TNFRSF10A rs13278062, and GATA5 rs6061548 genotypes with the natural course.

MAIN OUTCOME MEASURES

Incidence of CSC, pachychoroid neovasculopathy, and pachychoroid geographic atrophy (GA).

RESULTS

In total, 165 patients with unilateral CSC (mean age, 55.7 ± 12.6 years; female, 22.4%) were included from the Kyoto CSC cohort. Among them, 148 (89.7%) were diagnosed as having PPE in their non-CSC eye. Survival analysis revealed that 16.8% of PPE eyes developed CSC during the 6-year follow up, whereas non-PPE eyes did not. Although genetic factors did not have significant association with CSC development (P > 0.05, log-rank test), choroidal vascular hyperpermeability (CVH) and subfoveal choroidal thickness (SFCT) were significantly associated with CSC incidence (P = 0.001, log-rank test). Survival analysis showed that eyes without CVH and eyes with SFCT < 300 μm did not develop CSC during the 6-year follow-up. Pachychoroid neovasculopathy developed in only 1 eye with PPE during a follow-up of 46.4 months. Pachychoroid GA did not develop in any of the studied eyes.

CONCLUSIONS

This study revealed a natural history of PPE in a relatively large Japanese cohort. Choroidal vascular hyperpermeability and SFCT were significant risk factors for the development of CSC in PPE eyes. Although the current results cannot be generalized for all eyes with PPE, these findings present an important clinical implication.

Central serous chorioretinopathy: Treatment

Central serous chorioretinopathy (CSC) is a pachychoroid spectrum disease characterized by serous detachment of the neurosensory retina with subretinal fluid in young and middle-aged adults. The pathogenesis of CSC is not yet fully understood. However, it is considered a multifactorial disease that is strongly associated with choroidal dysfunction or vascular engorgement. Although there is no consensus on the treatment of CSC, photodynamic therapy has been effectively used to manage serous retinal detachment (SRD) in CSC. Moreover, micropulse diode laser photocoagulation and focal laser treatment have also been used. Recently, oral medications, including mineralocorticoid receptor antagonists, have been proposed for the management of CSC. Multimodal imaging plays a significant role in the diagnosis and treatment of CSC. Optical coherence tomography angiography (OCTA) has the advantage of detecting vascular flow in the retina and choroid layer, allowing for a better understanding of the pathology, severity, prognosis, and chronicity of CSC. In addition, early detection of choroidal neovascularization in CSC is possible using OCTA. This review article aims to provide a comprehensive and updated understanding of CSC, focusing on treatment.

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.

Quantitative analysis of choroidal vasculature in central serous chorioretinopathy using ultra-widefield swept-source optical coherence tomography angiography

We aimed to quantitatively compare the choroid blood flow and choroid thickness at the periphery among eyes with central serous chorioretinopathy (CSC), fellow eyes and healthy eyes using ultra-widefield swept-source optical coherence tomography angiography (UWF SS-OCTA). Retrospective analysis of 49 patients with CSC (98 eyes, including unaffected fellow eyes) and 49 age and sex matched controls were included. We obtained 3-dimensional data of vertical 20 mm × horizontal 24 mm × scan depth 6 mm, comprising 9 subfields (superotemporal, upper, superonasal, temporal, central, nasal, inferotemporal, lower, inferonasal regions). CSC eyes presented with greater density of large-vessel choroidal layer in all the 9 subfields compared with controls. Compared with normal eyes, CSC eyes had greater choroidal thickness (superotemporal, upper, superonasal, temporal, central, nasal, inferotemporal, and inferonasal subfields) and choroidal volume (superotemporal, upper, superonasal, temporal, central, and nasal subfields). Compared with control eyes, the choriocapillaris density in the superotemporal, inferotemporal and inferonasal subfields was greater in patients with CSC. Our study may provide further evidence for the congestion of vortex vein in the pathogenesis of CSC. UWF SS-OCTA can be used to evaluate the abnormalities of the choroidal structures even at the periphery in eyes with CSC.

Association between central serous chorioretinopathy susceptibility genes and choroidal parameters

PURPOSE

To evaluate the association between central serous chorioretinopathy (CSC) susceptibility genes and choroidal parameters in a large Japanese cohort.

STUDY DESIGN

Retrospective cohort study.

METHODS

Of the 9850 individuals in the Nagahama study whose second visit was between 2013 and 2016, those with optical coherence tomography (OCT) images with enhanced depth imaging (EDI), axial length, and genome-wide single nucleotide polymorphism (SNP) genotyping data were included. We calculated subfoveal choroidal thickness (SFCT), choroidal vascularity index (CVI), normalized choroidal intensity (NCI), and vertical asymmetry of choroidal thickness. Genome-wide quantitative trait locus (QTL) analyses were performed for each parameter. We screened for four CSC susceptibility SNPs: CFH rs800292, TNFRSF10A rs13278062, GATA5 rs6061548, and VIPR2 rs3793217. Whenever an SNP was not included in the genotyping data after quality control, its proxy SNP was selected.

RESULTS

In total, 4586 participants were evaluated. CFH rs800292 was significantly associated with SFCT (P < 0.001) and CVI (P < 0.001). VIPR2 rs3793217 was significantly associated with SFCT (P < 0.001) but not with CVI. Whereas, TNFRSF10A rs13254617 and GATA5 rs6061548 were not significantly associated with SFCT or CVI. None of these SNPs was associated with NCI_EDI and asymmetry of choroidal thickness.

CONCLUSION

CFH, VIPR2, TNFRSF10A, and GATA5 showed different association patterns with choroidal parameters. Although the mechanism of CSC pathogenesis by choroidal changes is not fully understood, this finding suggests that each gene may be involved in different mechanisms of CSC development. Our genetic study provides a basis for understanding the role of CSC susceptibility genes.

Wide-field OCT-angiography assessment of choroidal thickness and choriocapillaris in eyes with central serous chorioretinopathy

Purpose: To assess wide-field changes in choroidal thickness and choriocapillaris in eyes with central serous chorioretinopathy (CSC) compared with the fellow eyes and eyes from healthy individuals using wide-field swept-source (SS) OCT-Angiography (OCTA).

Methods: A cross-sectional study in which 68 eyes from 34 individual patients affected by unilateral CSC and 32 eyes of 32 age- and sex-matched healthy subjects were evaluated. All subjects underwent wide-field SS-OCTA examination to quantify choroidal thickness and vascular density of the choriocapillaris. To assess the wide-field changes, we developed five 4-by-4 mm square regions located in the posterior pole and in the four quadrants of the peripheral retina (superotemporal, inferotemporal, superonasal, and inferonasal subfields, respectively).

Results: The choroidal thickness of eyes with CSC was greater than that of the fellow eyes in the central and inferonasal subfields (p < 0.001 for the central subfield and p = 0.006 for the inferonasal subfield, respectively). Compared with the choroidal thickness of healthy eyes, that of patients with CSC were significantly greater in all the subfields (p < 0.05 for the fellow eyes and p < 0.05 for eyes with CSC, respectively). Compared with that of healthy eyes, the vascular density of choriocapillaris in eyes of patients with CSC were significantly greater in the central and superotemporal subfields (p < 0.05 for the fellow eyes and p < 0.05 for eyes with CSC, respectively). In the central region, the vascular density of choriocapillaris of the fellow eyes was greater than eyes with CSC (p = 0.023).

Conclusion: CSC appears to be a bilateral disease with asymmetric manifestations. Local factors of the diseased eyes may play an important role in the development of CSC, during which dynamic and regional changes in the choriocapillaris may have happened. Wide-field swept-source OCTA provided a useful tool to study the pathogenesis of CSC.

Pathogenic Risk Factors and Associated Outcomes in the Bullous Variant of Central Serous Chorioretinopathy

PURPOSE

To compare the clinical features, treatments, and outcomes between bullous and chronic variants of central serous chorioretinopathy (CSC).

DESIGN

Retrospective, observational case series.

PARTICIPANTS

Sixty-two eyes of 44 patients with bullous-variant CSC (bvCSC) and 97 eyes of 85 patients with nonbullous CSC.

METHODS

We conducted a national survey between September 1, 2020, and March 31, 2021, of members of the Korean Retina Society and obtained data of patients with bvCSC from 11 retinal centers. A comparator group comprised consecutive chronic CSC patients without bullous detachment.

MAIN OUTCOME MEASURES

Baseline demographics and patient characteristics were compared between groups. Secondary outcomes included factors associated with visual prognosis within the bvCSC group.

RESULTS

Compared with the nonbullous CSC group, the bvCSC group presented at a younger age (49 vs. 52 years; P = 0.047) and with more bilateral involvement (41% vs. 14%; P < 0.001). Systemic corticosteroid use was more prevalent in the bvCSC group, both in terms of any exposure (50% vs. 20%; P = 0.001) and long-term exposure (36% vs. 9%; P <  0.001). The bvCSC group had distinct imaging features (all P < 0.05): retinal folding (64% vs. 1%), subretinal fibrin (75% vs. 13%), multiple retinal pigment epithelium tears (24% vs. 2%), and multifocal fluorescein leakages with terminal telangiectasia (36% vs. 1%). Although bvCSC patients had worse vision at diagnosis (20/80 vs. 20/44; P =  0.003), treatment response was more robust (fluid resolution by final follow-up, 84% vs. 68%; P = 0.034) even with conservative management, resulting in similar final vision (20/52 vs. 20/45; P =  0.52). History of kidney-related (odds ratio [OR] 5.4; 95% confidence interval [CI] 1.3-18.5; P =  0.045) and autoimmune/rheumatoid diseases (OR 25.4, 95% CI 2.8-195.0; P =  0.004) showed associations with the bvCSC group. Apart from vision at diagnosis (OR 0.1, 95% CI 0.05-0.36; P  <  0.001), a history of renal transplantation was most predictive of visual prognoses for bvCSC eyes (OR 0.2, 95% CI 0.04-0.75; P  =  0.020).

CONCLUSIONS

Bullous-variant CSC may be associated with pathogenic risk factors based on underlying medical conditions and systemic corticosteroid use. Poor vision at diagnosis and history of renal transplantation were associated with poor visual outcome.

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.

En face ultra-widefield optical coherence tomography of the vortex vein system in central serous chorioretinopathy

PURPOSE

To investigate whether noninvasive en face ultrawidefield (UWF) OCT can demonstrate salient features of the choroidal vasculature in eyes with central serous chorioretinopathy (CSC).

DESIGN

Retrospective observational case series.

PARTICIPANTS

Patients diagnosed with CSC who underwent UWF indocyanine green angiography (ICGA) and widefield OCT imaging were included.

METHODS

Widefield OCT imaging was performed with a horizontal 23-mm × vertical 20-mm field of view of 5 visual fixations (1 central and 4 peripheral fixations) to compose structural en face UWF OCT montage images and UWF choroidal thickness maps. Automated image alignment was performed before grading.

MAIN OUTCOME MEASURES

A comparison of choroidal vascular findings seen with UWF ICGA and en face UWF OCT images, including size and distribution of choroidal venous drainage areas and identification of dilated choroidal veins (pachyvessels) crossing the physiologic choroidal watershed zones. The spatial correlation between choroidal vascular hyperpermeability on UWF ICGA images and areas of choroidal thickening on UWF choroidal thickness maps was determined.

RESULTS

Forty-two eyes from 27 patients with CSC with a mean age of 56 ± 12 years (range, 31-77 years) were included. Quantitative measures of vortex vein drainage areas on en face UWF OCT images were significantly and positively correlated with those obtained with UWF ICGA (mean Pearson r = 0.825, P < 0.01). Identification of pachyvessels crossing the choroidal watershed zones showed an excellent correlation between UWF ICGA and en face UWF OCT images (mean Spearman ρ = 0.873, P < 0.01). In all cases, choroidal vascular hyperpermeability was observed on UWF ICGA spatially colocalized with areas of choroidal thickening on the UWF choroidal thickness map. Congestion within the entire drainage area of the dominant vortex systems was observed on UWF choroidal thickness maps.

CONCLUSIONS

In eyes with CSC, noninvasive en face UWF OCT imaging can show distinctive features of choroidal venous insufficiency previously identified with UWF ICGA. Ultrawidefield OCT choroidal thickness maps enable quantitative assessment of choroidal congestion.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Three-dimensional choroidal vascularity index in central serous chorioretinopathy using ultra-widefield swept-source optical coherence tomography angiography

Background

To map and compare the three-dimensional choroidal vascularity index (3D-CVI) in eyes with unilateral central serous chorioretinopathy (CSC), fellow eyes and control eyes using ultra-widefield swept source optical coherence tomography (UWF SS-OCTA).

Methods

In this prospective observational study, the 3D-CVIs were measured in 9 subfields or 1 × 1 mm grids by the UWF SS-OCTA with a viewing angle of horizontal 24 × vertical 20 mm. The proportions of vortex vein anastomoses and their corresponding CVI in the central regions were compared among the CSC, fellow and control eyes. Correlations of CVI and vascular density of the large choroidal vessel layer/choriocapillaris layer/choroidal thickness (CT) were also assessed.

Results

Thirty-two eyes in 32 patients with unilateral CSC and 32 normal eyes were included in the study. The mean CVI in the eyes with CSC was significantly greater than that in the fellow eyes of CSC and control eyes (41.99 ± 3.56% vs. 40.38 ± 3.855%, P = 0.003; 41.99 ± 3.56% vs. 38.93 ± 4.067%, P = 0.004, respectively). The CVIs in superotemporal, inferotemporal and inferonasal regions were significantly higher in CSC eyes than control eyes (P = 0.03, P = 0.02, P = 0.008). In CSC eyes, there was a linear positive correlation between 3D-CVI and vascular density of the large choroidal vessel layer and CT in all subfields. The proportion of vortex vein anastomoses in CSC was 25/32 (78.1%), and significantly higher in fellow and control eyes (P < 0.001). The average central CVI was significantly higher in CSC eyes with anastomoses than in CSC eyes without anastomoses (42.8 ± 5.1% vs. 38.4 ± 2.7%, P = 0.039). CVIs in superior, central, inferior, superonasal, nasal and inferonasal regions were significantly correlated with vortex vein anastomoses (P < 0.05), regardless of CSC, fellow or healthy eyes. In addition, whether there were vortex vein anastomoses, CVI in superotemporal region was significantly higher in eyes with CSC (P = 0.002) and fellow eyes (P = 0.014), compared to control eyes. No significant correlation was found between hypertension and CVIs in the three groups.

Conclusion

Remodeling of choroidal drainage routes by venous anastomosis between superior and inferior vortex veins may be common in CSC. The 3D-CVI could be a comprehensive parameter to evaluate the choroid vasculature and help understand the pathogenesis of pachychoroid spectrum disease.

A new insight into pachychoroid diseases: Remodeling of choroidal vasculature

Purpose

Pachychoroid spectrum diseases are regarded as being different manifestations of a common pathogenic process. We suggest that pachychoroid diseases are consequences of chronic vortex vein stasis.

Methods

We describe how we came to this conclusion based on our own recent reports as well as a search of the related literature.

Results

Central serous chorioretinopathy (CSC) is the first stage of pachychoroid spectrum diseases. CSC is caused by congestion of choroidal veins, which are branches of the vortex veins. The venous outflow tract of the choroid is divided into four quadrants, based on horizontal and vertical watershed zones, with one or two vortex veins in each quadrant being independently responsible for venous outflow. In acute CSC, vortex vein stasis frequently causes asymmetric dilatation of the vortex veins in the horizontal watershed. The area of geographic filling delay in the choriocapillaris coincides with the area of this asymmetrically dilated vortex veins. With chronic stasis of the vortex veins, venous anastomosis occurs in the watershed zone as a means of compensating for the stasis, and the choriocapillaris becomes occluded in the area of filling delay. The anastomotic vessels dilate, becoming often hyperpermeable, and are then recognizable as pachyvessels. With the development of choriocapillaris ischemia, choroidal neovascularization (CNV) occurs at the site of pachyvessels. This is termed pachychoroid neovasculopathy (PNV). Polypoidal choroidal vasculopathy is regarded as a variant of PNV.

Conclusions

Intervortex venous anastomosis is among the key factors underlying the development of pachychoroid diseases. Remodeling of the venous drainage route though the anastomosis across the watershed zones is apparently a common response to chronic vortex vein stasis.

Pathophysiology of central serous chorioretinopathy: a literature review with quality assessment

The pathogenesis of central serous chorioretinopathy (CSCR), a pachychoroid disease, is poorly understood. While choroid hyperpermeability and retinal pigment epithelium dysfunction are cornerstones for developing CSCR, the mechanisms at the retinal, vascular, retinal pigment epithelium, and cellular level continue to be an enigma. A few preclinical studies and the development of small-sized, poorly controlled clinical trials have resulted in limited insight into the disease mechanism. Effective treatments for CSCR are still lacking as current trials have produced inconsistent results for functional and structural gains. Thus, critically evaluating the literature to explore disease mechanisms and provide an up-to-date understanding of pathophysiology can provide valuable information and avenues to new treatments. In this study, a comprehensive summary of the mechanistic insight into CSCR is presented while highlighting the shortcomings of current literature. The mechanism was divided into seven sub-categories including mechanical obstruction, inflammation, oxidative stress, paracrine factors, autonomic dysfunction, mineralocorticoid receptors activation, and medications. We implemented validated tools like the JBI and CAMARADES to objectively analyze the quality of both clinical and preclinical studies, respectively. Overall, our analysis of the literature showed that no single mechanism was populated with a large number of sufficiently sized and good-quality studies. However, compiling these studies gave hints not only to CSCR pathogenesis but also pachychoroid disease in general while providing suggestions for future exploration.

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.

PERIPHERAL CHOROIDAL THICKNESS DETERMINED BY WIDEFIELD OPTICAL COHERENCE TOMOGRAPHY IN EYES WITH CENTRAL SEROUS CHORIORETINOPATHY

PURPOSE

To determine the central and peripheral choroidal thickness in eyes with central serous chorioretinopathy (CSC), and to compare these thicknesses values to those of control normal eyes.

METHODS

Widefield optical coherence tomographic (WF-OCT) images of 24 eyes of 19 CSC patients and 14 normal eyes of 7 individuals were recorded. A 20 mm vertical scan through the fovea was obtained with the Xephilio OCT S1 (Canon, Japan), a widefield OCT device. The subfoveal choroidal thickness (SCT), and the thickness at 5 mm superior (S5) and inferior (I5), 7 mm superior (S7) and inferior (I7), 8.5 mm superior (S8) and inferior (I8), and 10 mm superior (S10) and inferior (I10) from the fovea in the CSC eyes and normal eyes were compared.Results: There was no significant difference in the age (P=0.8) or the refractive error (P=0.7) between the CSC and normal eyes. The choroidal thickness was significantly thicker in the eyes with CSC than that in the normal eyes at SCT (P<0.01), S5 (P=0.01), and S7 (P=0.02). However, there was no significant difference in the choroidal thickness at the more peripheral points (all P>0.1).

CONCLUSION

The thickened choroid in CSC was observed at the fovea and the area just superior to the fovea. The pathogenesis of CSC may be associated with the choroidal thickening confined to the fovea and superior foveal area.

Choroidal vascular alterations evaluated by ultra-widefield indocyanine green angiography in central serous chorioretinopathy

PURPOSE

This study aims to evaluate choroidal vascular alterations in patients with central serous chorioretinopathy (CSC) using ultra-widefield (UWF) indocyanine green angiography (ICGA).

METHODS

This was a retrospective case-control study conducted at a single tertiary eye center. In total, 36 eyes in patients with either unilateral (24 patients) or bilateral (six patients) treatment-naïve CSC and 30 eyes in 24 age-matched controls were evaluated. The number of quadrants with vortex vein engorgement on UWF ICGA was evaluated. Dilated choroidal vessels affecting the macula were regarded as extended vortex vein engorgement. Choroidal vascular hyperpermeability (CVH) area on late-phase ICGA was quantified using stereographic projection. The parameters were compared with clinical and optical coherence tomographic findings.

RESULTS

Eyes with CSC had larger CVH area, thicker choroid, and more quadrants with vortex vein engorgement and extended vortex vein engorgement compared with control eyes (all P < 0.001). In patients with unilateral CSC, affected eyes had larger CVH area, thicker choroid, and more extended vortex vein engorgements compared with unaffected fellow eyes (all P < 0.001), but vortex vein engorgement did not significantly differ. CVH was significantly correlated with extended vortex vein engorgement (P < 0.001) and subfoveal choroidal thickness (P = 0.007).

CONCLUSIONS

The increased number and binocular symmetry of engorged vortex veins suggest an anatomical predisposition for CSC. CVH area and extended vortex vein engorgement were indicators of choroidal outflow congestion. These parameters may serve as diagnostic clues or predictors of disease development in eyes with CSC.

Ultra-Widefield Indocyanine Green Angiography Reveals Patterns of Choroidal Venous Insufficiency Influencing Pachychoroid Disease

Purpose

To compare patterns of choroidal venous drainage in eyes with pachychoroid disease to those of healthy subjects using ultra-widefield indocyanine green angiography (UWF ICGA).

Methods

Patients with pachychoroid disease and healthy controls were recruited at two referral centers. UWF ICGA images were used to evaluate the proportion of the postequatorial fundus drained by major vortex vein systems in each quadrant and to study the incidence and topography of choroidal vascular hyperpermeability (CVH) and intervortex venous anastomoses. Widefield swept-source optical coherence tomography (SS-OCT) was used to evaluate choroidal thickness at the posterior pole in eyes with pachychoroid disease.

Results

Fifty-two pachychoroid eyes and 26 healthy eyes were evaluated. Eyes with pachychoroid disease showed a significant within-subject variance in the proportion of the postequatorial fundus drained by each vortex vein system (range, 4.1%–48.1%; P < 0.0001) that was not seen in controls (range, 17.3%–31.7%; P = 0.11). CVH was present in all pachychoroid disease eyes and three of 26 controls. Intervortex venous anastomoses were present in 46 of 52 pachychoroid disease eyes and nine of 26 control eyes. Vortex vein systems with large drainage areas showed greater density of CVH spots. SS-OCT demonstrated asymmetric choroidal drainage in the macula of 59% of pachychoroid eyes. CVH and intervortex venous anastomoses were more prominent in areas showing maximal choroidal thickness.

Conclusions

In eyes with pachychoroid disease, imbalanced choroidal venous drainage with congestion of specific vortex vein systems may contribute to a state of choroidal venous insufficiency characterized by regional choroidal thickening, CVH and remodeling of venous drainage routes.

Interocular asymmetry of choroidal thickness and vascularity index measurements in normal eyes assessed by swept-source optical coherence tomography

BACKGROUND

To investigate the symmetry of interocular choroidal thickness and vascularity index measurements in normal eyes using swept-source optical coherence tomography (SS-OCT). Cross-sectional and observational study. This study included 244 eyes of 122 normal adults with ages uniformly distributed from 19 to 89 years.

METHODS

SS-OCT imaging was performed using a scanning pattern of 12×12 mm. Mean choroidal thickness (MCT) and choroidal vascularity index (CVI) measurements in the entire scanning region were obtained using a validated and published automatic method. The correlation and differences (including signed and absolute differences) between bilateral MCT and CVI measurements were analyzed at the following 6 regions: 3 concentric circles centered on the fovea with diameters of 2.5, 5, and 11 mm; the inner rim from 2.5 to 5 mm circle; the outer rim from 5 to 11 mm circle; and the entire 12×12-mm scan region, respectively. Comparison of interocular MCT and CVI measurements.

RESULTS

MCT measurements in right and left eyes were strongly correlated in all regions [all intraclass correlation (ICC) >0.73], but MCT measurements in right eyes were significantly thicker than in left eyes. CVI measurements in right and left eyes were moderately correlated in all regions (all ICC >0.46), but CVI measurements in right eyes were significantly smaller than that in left eyes in the macular subregions (2.5 mm circle, 5 mm circle, and the inner rim). Neither signed nor absolute interocular differences in MCT were correlated with corresponding CVI interocular differences.

CONCLUSIONS

Choroidal differences exist between normal fellow eyes in adults in the absence of obvious pathology. This study is useful in assisting clinicians and researchers in distinguishing asymmetric changes that are to be expected in normal eyes versus changes that could be associated with diseases.

Imbalanced choroidal circulation in eyes with asymmetric dilated vortex vein

PURPOSE

Asymmetric dilated vortex vein (ADVV) observed in eyes with pachychoroid spectrum diseases is thought to be due to congestion of choroidal blood flow. The purpose of this study was to quantitatively investigate the blood flow velocity of ADVV using laser speckle flowgraphy (LSFG).

STUDY DESIGN

Retrospective case series.

METHODS

This was a retrospective case series with 23 eyes of 18 patients with ADVV on en-face OCT. A pair of choroidal veins from ADVV side (defined as ADVV vein) and non-ADVV side (defined as non-ADVV vein) was selected in each eye under the following criteria: (i) equivalent proximity to the deviated watershed, (ii) does not overlap with retinal blood vessels in the en-face OCT image, (iii) has approximately the same blood vessel diameter. Rubber bands were placed on the selected choroidal veins on the LSFG color map. Mean blur rate (MBR) values of ADVV and non-ADVV veins were statistically compared.

RESULTS

The average MBR was 10.11 ± 1.9 in the ADVV veins and 13.49 ± 6.2 in the non-ADVV veins, showing significantly lower values in the ADVV veins (P = 0.03). The blood vessel diameter of the ADVV was 10.26 ± 3.0 and in the non-ADVV veins, 10.63 ± 2.9 pixels; not significantly different (P = 0.66). The distance from the deviated watershed to the ADVV was 53.3 ± 24.8 and to the non-ADVV veins, 46.80 ± 20.3 pixels; not significantly different (P = 0.41).

CONCLUSION

In eyes with ADVV, the blood flow velocity in the ADVV veins was lower than in the non-ADVV veins, suggesting anatomical congestion of ADVV.

Short Axial Length Is Related to Asymmetric Vortex Veins in Central Serous Chorioretinopathy

Purpose

To investigate the clinical and morphologic factors related to asymmetric dilated vortex veins in central serous chorioretinopathy (CSC).

Design

Retrospective, comparative study.

Participants

One hundred fifty-eight eyes of 158 patients with CSC.

Methods

All patients with CSC underwent ophthalmic examination and multimodal imaging, including measurements of axial length (AL), fluorescein angiography, indocyanine green angiography, swept-source OCT, and anterior segment OCT. Using en face OCT images at the level of the outer choroid, the eyes were divided into 2 groups: eyes with symmetric vortex veins (symmetry group) and those with asymmetric vortex veins (asymmetry group).

Main Outcome Measures

Clinical and morphologic factors related to asymmetric vortex veins in CSC.

Results

Of the 158 eyes, 120 eyes (75.9%) were classified into the asymmetry group and 38 eyes (24.1%) were classified into the symmetry group. The asymmetry group showed significantly greater spherical equivalent (–0.32 ± 1.78 diopters [D] vs. –1.35 ± 2.64 D; P = 0.033), shorter AL (23.52 ± 0.86 mm vs. 24.10 ± 1.06 mm; P = 0.005), and greater subfoveal choroidal thickness (414.6 ± 105.3 μm vs. 360.4 ± 91.8 μm; P = 0.005) than the symmetry group. No significant differences existed between the 2 groups regarding age, sex, or all scleral thicknesses at the superior, temporal, inferior, and nasal points. In the multivariate analyses, shorter AL (odds ratio, 0.56; 95% confidence interval, 0.36–0.88; P = 0.011) was found to be significantly associated with the presence of asymmetric vortex veins.

Conclusions

The asymmetric dilated vortex vein is a common finding in patients with CSC. Our results suggest that certain biometric factors, such as short AL, may be associated with asymmetric dilated vortex veins developing in patients with CSC.

QUANTIFICATION OF VESSELS OF HALLER'S LAYER BASED ON EN-FACE OPTICAL COHERENCE TOMOGRAPHY IMAGES

PURPOSE

To quantify the vessels of Haller's layer of normal subjects in en-face optical coherence tomographic images.

METHODS

One hundred and seventy-two normal eyes were studied. En-face images of the top 25% slab of Haller's layer was analyzed. The vessel area, vessel length, and mean vessel diameter were calculated. The vessel running pattern was quantified for the degree of symmetry and designated as the "symmetry index." The coefficient of correlation between each choroidal parameter and the age, sex, axial length, and central choroidal thickness was determined.

RESULTS

The vessel area was 23.4 ± 3.6 mm2, vessel length was 164.6 ± 24.1 mm, mean vessel diameter was 0.143 ± 0.019 mm, and the symmetry index was 58.6 ± 6.1%. Multiple regression analysis showed that the vessel area was significantly correlated with the age (R = -0.421, P < 0.001) and central choroidal thickness (R = 0.315, P < 0.001). The vessel length was significantly correlated with the age (R = -0.391, P = 0.024) and central choroidal thickness (R = -0.410, P < 0.001). The mean vessel diameter was significantly correlated with the age (R = -0.107, P = 0.024) and central choroidal thickness (R = 0.775, P < 0.001). The correlation between the symmetry index and any clinical findings was not significant.

CONCLUSION

Quantification of en-face images of Haller's layer provide new biomarkers of the choroid.

Vortex Vein Imaging: What Can It Tell Us?

This review article summarizes the patho-anatomy of the vortex veins, the major drainage channels for the choroid, and describes the various pathways of diseases associated with vortex vein abnormalities. This report also details the technical advancements to image the vortex veins, such as ultra-widefield indocyanine green angiography, which are critical to elucidate the importance of the vortices in various retino-choroidal disorders. Future applications of these advanced imaging systems to better understand the role of the vortex veins in health and disease are also discussed.

Morphological differences of choroid in central serous chorioretinopathy determined by ultra-widefield optical coherence tomography

PURPOSE

The purpose of this study was to compare the morphology of the central and peripheral choroid of eyes with central serous chorioretinopathy (CSC) to that of normal eyes using ultra-widefield optical coherence tomography (UWF-OCT).

METHODS

We reviewed the medical records of 29 eyes of 25 patients (23 men, 2 women; average age 44.4 years) with CSC and 34 eyes of 22 healthy subjects (19 men, 3 women; average age, 49.5 years) with normal eyes. The images obtained by a prototype swept source UWF-OCT (Topcon, Tokyo, Japan) of about 31.5-mm wide and a depth of 10.9 mm were analyzed. The choroidal thickness was measured for each sector of the eye using the conventional automated layer analysis method. The local morphological differences were quantified by the maximum steepness (µm/deg) which was obtained by differentiating the changes in the choroidal thickness from the periphery to the fovea. Only the vertical scans were evaluated to avoid the influence of the optic disc.

RESULTS

The choroid was thicker in the macular area than the peripheral area in both normal and CSC eyes. The choroid at the subfovea was significantly thicker in the CSC eyes than that of the normal eyes (P < 0.0001); however, the difference at the periphery was not significant. The mean of the maximum steepness of the choroidal thickness was 20.8 ± 3.8 µm/deg in the CSC eyes which was significantly steeper than the 16.0 ± 4.6 µm/deg in healthy eyes (P < 0.0001).

CONCLUSION

The choroid in CSC eyes has a steeper slope around the posterior pole. UWF-OCT can be used to evaluate the abnormalities of the choroidal structures from the posterior pole to the periphery in eyes with CSC.

Chronic choriocapillaris ischemia in dilated vortex vein region in pachychoroid neovasculopathy

We evaluated choroidal congestion using multimodal imaging in pachychoroid neovasculopathy (PNV). In a retrospective case series of 100 eyes of 99 treatment-naïve PNV patients, their clinical records were reviewed and the corresponding multimodal imaging studies were analyzed. We assessed areas of choriocapillaris filling delay which overlapped with dilated outer choroidal vessels, choroidal neovascularization (CNV), and retinal pigment epithelium (RPE) atrophy. The study subjects were 78 men (78.8%) and 21 women (21.2%). The mean patient age was 67.5 ± 10.5 years. On indocyanine green angiography, all eyes showed choriocapillaris filling delay in the early phase. Dilated outer choroidal vessels were demonstrated in all eyes by en face optical coherence tomography. The areas of choriocapillaris filling delay overlapped extensively with that of dilated outer choroidal vessels. All eyes showed CNV localized within the sites of choriocapillaris filling delay. RPE atrophy was noted in 71 eyes (71.0%), and 68 of these (95.8%) had RPE atrophy within the areas showing choriocapillaris filling delay. These findings indicate that chronic choriocapillaris ischemia secondary to vortex vein congestion may lead to CNV development as well as RPE atrophy in eyes with PNV.

Venous overload choroidopathy: A hypothetical framework for central serous chorioretinopathy and allied disorders

In central serous chorioretinopathy (CSC), the macula is detached because of fluid leakage at the level of the retinal pigment epithelium. The fluid appears to originate from choroidal vascular hyperpermeability, but the etiology for the fluid is controversial. The choroidal vascular findings as elucidated by recent optical coherence tomography (OCT) and wide-field indocyanine green (ICG) angiographic evaluation show eyes with CSC have many of the same venous patterns that are found in eyes following occlusion of the vortex veins or carotid cavernous sinus fistulas (CCSF). The eyes show delayed choroidal filling, dilated veins, intervortex venous anastomoses, and choroidal vascular hyperpermeability. While patients with occlusion of the vortex veins or CCSF have extraocular abnormalities accounting for the venous outflow problems, eyes with CSC appear to have venous outflow abnormalities as an intrinsic phenomenon. Control of venous outflow from the eye involves a Starling resistor effect, which appears to be abnormal in CSC. Similar choroidal vascular abnormalities have been found in peripapillary pachychoroid syndrome. However, peripapillary pachychoroid syndrome has intervortex venous anastomoses located in the peripapillary region while in CSC these are seen to be located in the macular region. Spaceflight associated neuro-ocular syndrome appears to share many of the pathophysiologic problems of abnormal venous outflow from the choroid along with a host of associated abnormalities. These diseases vary according to their underlying etiologies but are linked by the venous decompensation in the choroid that leads to significant vision loss. Choroidal venous overload provides a unifying concept and theory for an improved understanding of the pathophysiology and classification of a group of diseases to a greater extent than previous proposals.

Artificial intelligence for classifying uncertain images by humans in determining choroidal vascular running pattern and comparisons with automated classification between artificial intelligence

Purpose

Abnormalities of the running pattern of choroidal vessel have been reported in eyes with pachychoroid diseases. However, it is difficult for clinicians to judge the running pattern with high reproducibility. Thus, the purpose of this study was to compare the degree of concordance of the running pattern of the choroidal vessels between that determined by artificial intelligence (AI) to that determined by experienced clinicians.

Methods

The running pattern of the choroidal vessels in en face images of Haller’s layer of 413 normal and pachychoroid diseased eyes was classified as symmetrical or asymmetrical by human raters and by three supervised machine learning models; the support vector machine (SVM), Xception, and random forest models. The data from the human raters were used as the supervised data. The accuracy rates of the human raters and the certainty of AI’s answers were compared using confidence scores (CSs).

Results

The choroidal vascular running pattern could be determined by each AI model with an area under the curve better than 0.94. The random forest method was able to discriminate with the highest accuracy among the three AIs. In the CS analyses, the percentage of certainty was highest (66.4%) and that of uncertainty was lowest (6.1%) in the agreement group. On the other hand, the rate of uncertainty was highest (27.3%) in the disagreement group.

Conclusion

AI algorithm can automatically classify with ambiguous criteria the presence or absence of a symmetrical blood vessel running pattern of the choroid. The classification was as good as that of supervised humans in accuracy and reproducibility.

A pilot study of scleral thickness in central serous chorioretinopathy using anterior segment optical coherence tomography

The aim of this study is to compare the scleral thickness of central serous chorioretinopathy (CSC) eyes with controls using anterior segment optical coherence tomography (AS OCT). This prospective case control study included 15 patients (15 eyes) with CSC and 15 age and gender matched healthy subjects. All subjects underwent spectral domain OCT with enhanced depth imaging and swept source AS OCT of temporal sclera. We investigated difference in scleral thickness between the two groups and relationship between choroidal and scleral thickness. Among the 15 eyes in the study group, 1 eye had acute CSC, 4 had recurrent CSC, 7 had inactive CSC, and 3 had chronic CSC. There was no significant difference in terms of age, gender, axial length and spherical equivalent between the two groups. The choroidal and scleral thickness of the study group were significantly greater than those of the control group (P < 0.001, P = 0.034). Choroidal thickness was positively correlated with scleral thickness (P = 0.031). A thick sclera along with a thick choroid were demonstrated in CSC eyes using AS OCT. Scleral characteristics might be involved in the pathogenesis of CSC by affecting outflow resistance of venous drainage in choroidal circulation.