Choroidal thickness in central serous chorioretinopathy

Choroidal and Choriocapillaris Changes after Photodynamic Therapy and Subthreshold Micropulse Laser Treatment for Central Serous Chorioretinopathy

Background and Objectives: The aim of the present study is to analyze choroidal and choriocapillaris structural and functional changes in eyes affected by Central serous chorioretinopathy after Photodynamic Therapy (PDT) and Subthreshold Micropulse laser (SML) treatment. Materials and Methods: Forty-two eyes of forty-two patients were analyzed in this observational study. Twenty-four patients underwent SML treatment, whereas eighteen patients were treated with PDT. Examinations were performed at baseline and after 3 months of treatment. Main outcome measures were: Best corrected visual acuity (BCVA), central macular thickness (CMT), central choroidal thickness (CCT), pigment epithelial detachment (PED) presence and maximum height (PEDMH), and choroidal vascularity index (CVI) measured by means of Spectralis HRA + OCT (Heidelberg Engineering, Heidelberg, Germany) Optical coherence tomography (OCT) and choriocapillaris flow voids (CCFV) measured on Optical Coherence Tomography Angiography (OCT-A) platform PLEX Elite 9000 device (Carl Zeiss Meditec Inc., Dublin, CA, USA). Results: Changes in BCVA were registered in both groups over time (p < 0.001). Structural changes in terms of reduced CMT and PED presence were noted in the two groups at follow-up (p < 0.001 and p = 0.001, respectively). Structural and functional choroidal changes were found in the two groups with reduced CCT and CVI over time (p = 0.004 and p = 0.007, respectively), with significant differences between the two groups for CVI parameter (p = 0.001). CCFV increased over time in the PDT group and decreased in the SML group. Conclusions: PDT and SML are effective approaches in CSC eyes and are able to improve structural and functional parameters over time. Choroidal and choriocapillaris parameters are promising biomarkers able to monitor disease course, showing greater impact of PDT on choroid-choriocapillaris complex over time.

Changes in the outer nuclear layer and choroidal vascularity during the manifest and quiescent phases of acute central serous chorioretinopathy

To investigate alteration of outer nuclear layer (ONL) and choroidal vascularity index (CVI) in different status of central serous chorioretinopathy (CSC). A retrospective review of 65 CSC eyes with subretinal fluid (manifest CSC) and 40 control eyes was conducted in a single tertiary university hospital. Differences in best-corrected visual acuity (BCVA), ONL, and CVI were compared. CVI was assessed both in the entire choroid (CVI-EC) and around the 1500 μm leakage area (CVI-1500). Measurements were repeated after the subretinal fluid resorption (quiescent CSC), and compared. CSC eyes showed worse BCVA, thinner ONL and greater CVI than controls. Quiescent CSC showed a recovery of ONL compared to the manifest CSC, along with the BCVA improvement. The resolution of the CSC revealed a decrease across all three choroidal areas (total, stromal and luminal), with a more pronounced reduction in the stromal than in the luminal choroidal area, leading to an increase in the CVI. This phenomenon was shown in both CVI-EC and CVI-1500. Conclusively, ONL thickness can be used as a quantitative biomarker for photoreceptor function in CSC. Increased CVI may reflect a disease activity. The stromal choroidal area is particularly sensitive in illustrating leakage from the choroidal vasculature.

Central serous chorioretinopathy: updates in the pathogenesis, diagnosis and therapeutic strategies

Central serous chorioretinopathy (CSCR), first described by Albrecht von Graefe in 1866, is characterized by focal serous detachment of the neural retina and/or retinal pigment epithelium (RPE) in the posterior pole. CSCR is the first ever described pachychoroid disease. Most recently, hypothetical venous overload choroidopathy is also proposed due to its distinguished morphological and pathological characteristics, including choroidal thickening, choriocapillaris hyperpermeability, remodelling, and intervortex venous anastomoses. Identification of genetic variants is necessary to comprehend the pathophysiology of CSCR. The novel multimodality imaging platforms, including the ultra-widefield imaging system, flavoprotein fluorescence, fluorescence lifetime imaging ophthalmoscopy, and multispectral imaging system, have been used for diagnosing and managing CSCR. Half-dose photodynamic therapy (PDT) remains the mainstay of clinical practice, with about 95% of patients with chronic CSCR improving to visual acuity (VA) of 20/30 or better. The use of oral eplerenone for routine clinical care remains controversial, and long-term randomized clinical trials are warranted to investigate its efficacy in acute and chronic CSCR. While CSCR has generally been recognized as a self-limiting disease with good prognosis, the underlying pathogenesis is still not fully understood, and treatments are often not fully effective. With new evidence emerging about pachydrusen being a disease precursor in both CSCR and polypoidal choroidal vasculopathy (PCV), it would be interesting to investigate whether CSCR can be a precursor to PCV. In this review, we highlighted the currently available evidence on the pathogenesis, diagnosis, multimodality imaging features, and management strategies, including recent findings related to CSCR.

Comparison of the morphological characteristics of the choroidal sublayer between idiopathic macular holes and epiretinal membranes with automatic analysis

PURPOSE

To compare the choroidal sublayer morphologic features between idiopathic macular hole (IMH) and idiopathic epiretinal membrane (iERM) on spectral-domain optical coherent tomography (SD-OCT) using an automatic segmentation model.

METHODS

Thirty-three patients with idiopathic IMHs and 44 with iERMs who underwent vitrectomies were involved. The enhanced depth imaging mode of SD-OCT was used to obtain the B-scan image after single line scanning of the macular fovea. The choroidal sublayer automatic analysis model divides the choroidal into the choroidal large vessel layer, the middle vessel layer and the small vessel layer (LVCL, MVCL and SVCL, respectively) and calculates the choroidal thickness (overall, LVCL, MVCL and SVCL) and vascular index (overall, LVCL, MVCL and SVCL). The morphological characteristics of the choroidal sublayer in the ERM eyes and the IMH eyes were compared.

RESULTS

The mean choroidal thickness in the macular centre of the IMH eyes was significantly thinner than that of the ERM eyes (206.35 ± 81.72 vs. 273.33 ± 82.31 μm; P < 0.001). The analysis of the choroidal sublayer showed that the MVCL and SVCL macular centres and 0.5-1.5 mm of the nasal and temporal macula were significantly thinner in the IMH eyes than in the ERM eyes (P < 0.05), and there was a difference in the macular centre of the LVCL between the two groups (P < 0.05). In contrast, the choroidal vascular index of the macular centre in the IMH eyes was significantly higher than that in iERM eyes (0.2480 ± 0.0536 vs. 0.2120 ± 0.0616; P < 0.05). There was no significant difference in the CVI of other parts of the macula, the LVCL or MVCL between the two groups.

CONCLUSION

The choroidal thickness of the IMH eyes was significantly thinner than that of the iERM eyes, which was mainly observed in 3 mm of the macular centre and the MVCL and SVCL layers of the choroid. The choroidal vascular index of the IMH eyes was higher than that of the iERM eyes. These findings suggest that the choroid may be involved in the pathogenesis of IMH and iERM.

A Deep Learning-Based Fully Automated Program for Choroidal Structure Analysis Within the Region of Interest in Myopic Children

Purpose

To develop and validate a fully automated program for choroidal structure analysis within a 1500-µm-wide region of interest centered on the fovea (deep learning-based choroidal structure assessment program [DCAP]).

Methods

A total of 2162 fovea-centered radial swept-source optical coherence tomography (SS-OCT) B-scans from 162 myopic children with cycloplegic spherical equivalent refraction ranging from -1.00 to -5.00 diopters were collected to develop the DCAP. Medical Transformer network and Small Attention U-Net were used to automatically segment the choroid boundaries and the nulla (the deepest point within the fovea). Automatic denoising based on choroidal vessel luminance and binarization were applied to isolate choroidal luminal/stromal areas. To further compare the DCAP with the traditional handcrafted method, the luminal/stromal areas and choroidal vascularity index (CVI) values for 20 OCT images were measured by three graders and the DCAP separately. Intraclass correlation coefficients (ICCs) and limits of agreement were used for agreement analysis.

Results

The mean ± SD pixel-wise distances from the predicted choroidal inner, outer boundary, and nulla to the ground truth were 1.40 ± 1.23, 5.40 ± 2.24, and 1.92 ± 1.13 pixels, respectively. The mean times required for choroidal structure analysis were 1.00, 438.00 ± 75.88, 393.25 ± 78.77, and 410.10 ± 56.03 seconds per image for the DCAP and three graders, respectively. Agreement between the automatic and manual area measurements was excellent (ICCs > 0.900) but poor for the CVI (0.627; 95% confidence interval, 0.279-0.832). Additionally, the DCAP demonstrated better intersession repeatability.

Conclusions

The DCAP is faster than manual methods. Also, it was able to reduce the intra-/intergrader and intersession variations to a small extent.

Translational Relevance

The DCAP could aid in choroidal structure assessment.

Genetic Variability of Complement Factor H Has Ethnicity-Specific Associations With Choroidal Thickness

Purpose

To identify genetic alleles associated with differences in choroidal thickness (CT) in a population-based multiethnic Asian cohort.

Methods

A population-based multiethnic Asian cohort without retinal pathology was subjected to spectral-domain OCT (SD-OCT) and genotyping of risk alleles in CFH, VIPR2, ARMS2, and CETP. Subfoveal choroidal thickness (SFCT) values were assessed from SD-OCT, and associations with the risk alleles were determined for each cohort.

Results

A total of 1045 healthy Asian individuals (550 Chinese, 147 Indians, 348 Malays) were prospectively enrolled in the study. Several CFH alleles (rs800292, rs1061170, and rs1329428) were associated with increased SFCT in Indians (+18.7 to +31.7 µm; P = 0.001-0.038) and marginally associated with decreased SFCT in Malays (-12.7 to -20.6 µm; P = 0.014-0.022). Haplotype analysis of CFH revealed variable associations with SFCT among races, with the H6 haplotype being associated with a 29.08-µm reduction in SFCT in the Chinese cohort (P = 0.02) but a 35.2-µm increase in SFCT in the Indian cohort (P < 0.001). Finally, subfield analysis of the Chinese cohort identified associations between the CFH risk allele rs1061170 and reduced CT in the nasal and superior sectors (-20.2 to -25.8 µm; P = 0.003-0.027).

Conclusions

CFH variants are variably associated with CT among Asian ethnic groups. This has broad implications for the pathogenesis of common diseases such as age-related macular degeneration and central serous choroidopathy, the pathogenesis of which is associated with CT.

Central serous chorioretinopathy: A review

Central serous chorioretinopathy (CSC) is the fourth most common non-surgical retinopathy associated with fluid leakage. The pathogenesis is not yet completely understood, but changes in the choroid, sclera and RPE have been described associated with venous congestion of choroidal outflow. CSC can be categorised into acute, chronic, and recurrent subtypes with recent classifications of simple and complex based on the area of RPE change seen on fundus autofluorescence. A multimodal imaging approach is helpful in the diagnosis and management of CSC and secondary complications such as type 1 neovascularisation. Although spontaneous resolution with relatively good visual outcomes is common, treatment should be considered in patients with persistent or recurrent SRF. Treatment options include laser, systemic medications, intravitreal therapy, and surgery. Of these, argon laser for focal extramacular fluid leaks and photodynamic therapy of leakage identified by indocyanine-green angiography currently have the greatest supportive evidence.

The effect of off-pump coronary bypass graft surgery on subfoveal choroidal thickness, ganglion cell complex, and retinal nerve fiber layer thickness

Background

Cardiac surgery has been associated with adverse ocular events. Off-pump coronary artery bypass graft surgery evades the systemic inflammatory response seen in extracorporeal circulation and is superior to on-pump surgery with regard to end-organ dysfunction and neurological outcomes.

Objectives

To determine the effects of off-pump (without extracorporeal circulation) coronary artery bypass graft surgery on choroidal thickness, ganglion cell complex, and the retinal nerve fiber layer.

Design

Prospective, longitudinal study.

Methods

Patients who underwent off-pump surgery were examined preoperatively and postoperatively at 1 week and 6 weeks after surgery. Choroidal thickness, ganglion cell complex, and the retinal nerve fiber layer measurements were recorded, and the effects of off-pump coronary artery bypass on these parameters were assessed.

Results

A total of 44 eyes of 44 patients were included in the study. There was a statistically significant increase in subfoveal choroidal thickness from 252.84 ± 56.24 µm preoperatively to 273.82 ± 39.76 µm at 1 week and 301.97 ± 44.83 µm at 6 weeks after off-pump coronary artery bypass graft surgery (p = 0.044; p ⩽ 0.001). Ganglion cell complex and retinal nerve fiber measurements showed no significant difference compared to preoperative values.

Conclusion

Off-pump coronary artery bypass graft surgery showed no negative effects on ganglion cell complex and retinal nerve fiber measurements. A significant increase in subfoveal choroidal thickness was seen after off-pump surgery, which might be advantageous in patients who are at high risk or have preexisting ocular diseases that are affected by the choroid.

One-year follow-up of choroidal and macular thickness in acute non-treated central serous chorioretinopathy

CLINICAL RELEVANCE

Choroidal and macular thickness assessments are essential to understand the evolution of central serous chorioretinopathy and could help in identifying patients more prone to recurrence.

BACKGROUND

The aim of this work was to evaluate changes in the choroidal thickness and macular thickness in acute non-treated central serous chorioretinopathy during a one-year follow-up.

METHODS

A prospective longitudinal study of 38 patients with central serous chorioretinopathy and 35 healthy controls at a tertiary care facility (Fundación Alcorcón University Hospital) was conducted. Choroidal and macular thicknesses were measured using enhanced-depth-imaging optical coherence tomography and subretinal fluid resolution and best-corrected visual acuity were evaluated, at baseline and 1, 3, 6 and 12 months. Prognostic factors determining the need for treatment were evaluated.

RESULTS

Choroidal thickness decreased in eyes with central serous chorioretinopathy (p < 0.001) but not in fellow eyes (p = 0.24) during one-year follow-up since the acute episode. The estimated mean choroidal thickness in symptomatic eyes was 465 µm (SE: 17.18) at baseline and decreased 58.1 µm (CI 95%: 30.1-85.9) at 12 months (p < 0.001). Best-corrected visual acuity improved over time (p = 0.037), with a decrease of logMAR 0.086 (CI95%: 0-0.172).The macular thickness changed over time (p < 0.001), with a decrease from baseline of 124.6 µm (CI95%: 61.4-187.9). Subretinal fluid resolved in 67% (CI 95%: 51-82) of patients at 6 months. There was no significant association between baseline choroidal thickness, macular thickness, best-corrected visual acuity, age or sex and the need for treatment.

CONCLUSIONS

The choroidal thickness decreased in acute central serous chorioretinopathy episodes during a one-year follow-up. Subretinal fluid persisted in less than 20% of patients at the end of the one-year follow-up. No prognostic factors determining the need for treatment were found.

Functionality of retinal vessels in central serous retinopathy: A comparison between eplerenone and photodynamic therapy

Purpose

To investigate retinal vessels functionality in patients with acute central serous chorioretinopathy (CSC) undergoing oral eplerenone or photodynamic therapy (PDT) using Retinal Vessel Analyzer (RVA) and Dynamic Vessel Analyzer (DVA), respectively.

Methods

Treatment naïve acute CSC patients presenting between May 2017 and June 2017 were recruited. A complete ophthalmological examination was performed in all participants before and after oral eplerenone (eplerenone group) or half-dose PDT (PDT group).

Results

Eighteen eyes of 18 patients affected by acute CSC underwent either oral eplerenone (10 eyes of 10 patients, 47.6 ± 8.9 years old) or half-dose PDT (8 eyes of 8 patients, 57.4 ± 6.2 years old), respectively. After 2 months of treatment, non-significant variations of static retinal vessels analysis, dynamic arterial and venous dilatation were reported in eplerenone group. Similarly, in PDT group non-significant variations of static retinal vessels analysis, dynamic arterial and venous dilatation were found after 2 months of treatment.

Conclusions

Static and dynamic retinal functionalities in acute CSC may not be significantly improved by oral eplerenone and half-dose PDT. Although their choroidal effects, these treatments could not exert a significant effect on retinal vessels motility. Thus, both local and systemic therapies might not help avoiding the onset of vascular and other retinal known alterations of 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.

The Association of Pachydrusen Characteristics with Choroidal Thickness and Patient's Age in Polypoidal Choroidal Vasculopathy versus Central Serous Chorioretinopathy

We investigated the relationship between pachydrusen and choroidal thickness and age in eyes with polypoidal choroidal vasculopathy (PCV) and fellow eyes, compared to eyes with central serous chorioretinopathy (CSC). This retrospective study included 89 eyes with PCV and 146 eyes with CSC. The number, location, and shape of the pachydrusen and their association with choroidal thickness and age were analyzed. PCV eyes showed pachydrusen more frequently than eyes with CSC (52% vs. 20%, p < 0.001). Large solitary type and clustered type were more frequent in PCV eyes compared to CSC eyes (p = 0.003 and p = 0.001, respectively). Subfoveal choroidal thickness was associated with pachydrusen in eyes with PCV (odds ratio [OR] 1.006, 95% confidence interval [CI] 1.001−1.011, p = 0.027), while age was associated with pachydrusen in CSC eyes (OR 1.137, 95% CI, 1.073−1.205; p < 0.001). Pachydrusen were localized directly over the pachyvessel on optical coherence tomographic findings in approximately two thirds of PCV eyes and fellow eyes (62% and 67%, respectively). Risk factors for pachydrusen differ according to diseases. The presence of pachydrusen was associated with choroidal thickness in PCV, while the association with age was more prominent in CSC.

Changes in the Choroidal Thickness following Intravitreal Bevacizumab Injection in Chronic Central Serous Chorioretinopathy

We evaluated the effect of intravitreal bevacizumab injection (IVB) on choroidal thickness, and studied its association with the therapeutic response in chronic central serous chorioretinopathy (CSC). The clinical features of 78 eyes with chronic CSC treated with IVB from October 2014 to June 2020 were retrospectively evaluated. Visual acuity (VA), central retinal thickness (CRT), and sub-foveal choroidal thickness (SFCT) were analyzed at baseline, 1 month following initial IVB, and the last follow-up examination. Cases showing complete recovery (resolved eyes; n = 60) were compared with those with persistent subretinal fluid (refractory eyes; n = 18). The relationship between the potential risk factors and subretinal fluid resolution was examined using logistic regression. SFCT was significantly decreased along with the CRT following IVB at the resolved state. SFCT reduction following 1 month of IVB was notably greater in the resolved eyes. The association of refractory eyes with hypertension (p = 0.003) and a thinner baseline SFCT (p = 0.024) was significant. In most of the patients with chronic CSC, VA and CRT remarkably improved following treatment with IVB. Early changes in the SFCT following IVB were associated with the therapeutic response. Patients with hypertension and a thinner baseline SFCT could be unresponsive to IVB.

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.

The Effect of Obstructive Sleep Apnea Treatment and Severity on Choroidal Thickness in Patients With Central Serous Chorioretinopathy

Purpose:

This work aimed to analyze the association of obstructive sleep apnea (OSA) with choroidal thickness (CT) in patients with central serous chorioretinopathy (CSC).

Methods:

We identified patients in the Stanford Research Repository with a diagnosis of CSC and OSA. Age- and sex-matched controls with either CSC or OSA only were also identified. CT was measured at 5 points (subfoveal, and 1500 and 3000 µm nasal and temporal) by 2 graders. In addition to OSA treatment and severity, we also investigated the association of Oxygen Desaturation Index and nocturnal oxygen saturation nadir with subfoveal CT (SFCT).

Results:

A total of 57 patients and 72 eyes met the study inclusion criteria. The mean SFCT was significantly different across the 3 groups: OSA-only was the thinnest, followed by CSC with OSA, and CSC-only was the thickest (194.2 μm, 295.1 μm, and 357.8 μm, respectively, P < .001). SFCT was thicker in CSC with OSA compared with those with only OSA ( P < .05). OSA treatment status and OSA severity did not show a significant difference in SFCT in multivariable modeling. Nocturnal oxygen saturation nadir was positively associated with SFCT, but this did not reach significance..

Conclusions:

SFCT is significantly different in patients with OSA alone, CSC with OSA, and CSC alone. While OSA treatment status did not demonstrate a significant difference in SFCT in this study, future studies should evaluate patients for OSA in patients known to have CSC and atypically thin CT to further investigate the novel metrics leveraged in this study.

Choroidal Thickness Profile in Chorioretinal Diseases: Beyond the Macula

Enhanced depth imaging optical coherence tomography (EDI-OCT) and swept-source OCT (SS-OCT) have emerged as essential diagnostic tools in the study and management of various chorioretinal diseases. Evidence from early clinical studies using EDI-OCT and SS-OCT indicates that choroidal dysfunction plays a major role in the pathogenesis of chorioretinal diseases. Measurement of choroidal thickness (CT) has already become a major research and clinical method, and CT is considered as an indicator of choroidal status in a variety of ophthalmic diseases. Recently, CT measurement has also been proposed as a non-invasive marker for the early detection and monitoring of various systemic diseases. Among the several possible CT measurement locations, subfoveal CT has rapidly become a reliable parameter for measuring CT in healthy and diseased eyes. Moreover, recent advancements in OCT technology have enabled faster and wider imaging of the posterior part of the eye, allowing the various changes in CT as measured outside the macula to be shown accordingly. In this review, we first provide an overview of the results of clinical studies that have analyzed the healthy macular choroid and that in various chorioretinal diseases, and then summarize the current understanding of the choroid outside the macula. We also examine the CT profile as an index that encompasses both within and outside of the macula. Furthermore, we describe the clinical applications of ultrawide OCT, which enables visualization of the far periphery, and discuss the prospects for the development of more reliable choroidal parameters that can better reflect the choroid's characteristics.

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.

Choroidal vascularity index in adults with different refractive status

AIM

We aimed to perform structural analysis of the choroid in adults with different refractive status.

MATERIALS AND METHODS

A prospective, comparative study of 100 right eyes of 100 patients ages 18-40 years was conducted. The patients were divided into four groups according to spherical equivalent (SE): Group 1: -0.5 and above, low-to-moderate myopia; Group 2: -6 and above, high myopia; Group 3: +0.5 and above, hyperopia; Group 4: +/- 0.5, emmetropia. With the images obtained using enhanced depth imaging optical coherence tomography (EDI-OCT), the total choroidal area (TCA), luminal area (LA), stromal area (SA), and choroidal vascular index (CVI) were calculated using the binarization method. The anterior chamber depth (ACD), axial length (AL), and central corneal thickness (CCT) values were measured by optical biometry. All parameters were compared between groups. The correlation of biometric parameters with CVI was examined.

RESULTS

Parameters were found to be statistically different between the four groups. TCA, LA, and SA values were the highest in Group 3 and lowest in Group 2. L/S ratio and CVI values in Group 3 were significantly lower than in the other groups. There was a negative correlation between AL with SE and CT, and no correlation between the CVI and other parameters.

CONCLUSION

CVI decreases when emmetropization is disrupted and changes to hypermetropia or myopia. The reason for the decrease in myopia is the reduction of the luminal area, while in hyperopia it is due to an increase in the stromal area. When there is a shift toward myopia, there is a decrease in the TCA, but the CVI does not change significantly. Unlike CT, the CVI is not affected by factors such as SE and AL; therefore, the CVI can be a useful parameter for examining choroidal changes in refractive errors.

Pachychoroid spectrum disease

Recent improvements in ophthalmic imaging have led to the identification of a thickened choroid or pachychoroid to be associated with a number of retinal diseases. The number of conditions linked to this phenotype has continued to widen with specific endophenotypes found within the pachychoroid spectrum. The spectrum includes choroidal features such as focal or diffuse choroidal thickening and thinning of the overlying inner choroid, and choroidal hyperpermeability as demonstrated by indocyanine green angiography. In addition, these diseases are associated with overlying retinal pigmentary changes and retinal pigment epithelial dysfunction and may also be associated with choroidal neovascularization. This article provides a comprehensive review of the literature looking at diseases currently described within the pachychoroid spectrum including central serous chorioretinopathy, pachychoroid pigment epitheliopathy, pachychoroid neovasculopathy, polypoidal choroidal vasculopathy/aneurysmal type 1 neovascularization, peripapillary pachychoroid disease and focal choroidal excavation. We particularly focus on clinical imaging, genetics and pathological findings in these conditions with the aim of updating evidence suggesting a common aetiology between diseases within the pachychoroid spectrum.

Clinical characteristics of central serous chorioretinopathy in patients by age

PURPOSE

To investigate the clinical characteristics of central serous chorioretinopathy (CSC) with age.

STUDY DESIGN

Retrospective, cross-sectional study.

METHODS

One-hundred and forty-seven CSC patients were classified into three age groups (aged <50 years (younger group; n=53), 50-70 years (middle group; n=68), and >70 years (senior group; n=26)) and the characteristics were compared. Bilateral ophthalmic evaluation included the best corrected visual acuity (BCVA), spherical equivalents, fundus examination, fundus autofluorescence, optical coherence tomography (OCT), fluorescein angiography (FA), and indocyanine green angiography.

RESULTS

The male/female ratio became lower at more advanced ages (P=0.011). Bilateral macular abnormalities were observed more frequently in the senior group than the other groups (p=0.018) and multiple drusen were characteristic in the senior group (p<0.0001). The more advanced age groups displayed a worse BCVA (P=0.002). The rate of eyes with flat retinal pigment epithelium (RPE) elevation on OCT was significantly higher in the middle group than the other groups (P=0.024). The mean subfoveal choroidal thickness (SCT) was thickest in the younger group (P<0.0001). Unifocal leakage on FA and choroidal vascular hyperpermeability were mostly found in eyes of the younger group (P<0.001,P=0.020).

CONCLUSION

CSC cases in those aged >70 years were associated with an increased proportion of women and having bilateral macular abnormalities, multiple drusen, and multifocal leakage sites. The BCVA and the SCT decreased with age. Patients with CSC aged 50-70 years had the highest rate of flat RPE elevation on OCT. These characteristics need to be considered to make an accurate diagnosis, particularly in elderly patients.

Applications of Multimodal Imaging in Central Serous Chorioretinopathy Evaluation

Central serous chorioretinopathy (CSCR) is a macular disease characterized by serous retinal detachment commonly involving the macular region. CSCR has a wide spectrum of clinical presentations. Although a significant proportion of CSCR cases are self-limiting, patients can suffer from persistent or recurrent disease, sometimes complicated with choroidal neovascularization, resulting in permanent visual loss. Multimodal imaging, including fluorescein angiography, indocyanine green angiography, fundus autofluorescence, and optical coherence tomography, has advanced the diagnosis and classification of CSCR cases. Evolution of new imaging techniques including optical coherence tomography angiography, wide-field imaging, and en face reconstruction imaging has also contributed to better understandings of the pathophysiology of CSCR. This review article summarizes the features of multimodal imaging for CSCR and discusses the application of such features in evaluating the disease.

Evaluation of choroidal thickness in light-coloured eyes

OBJECTIVE

The aim of this study was to determine whether iris colour is related to the choroidal thickness of healthy individuals.

METHODS

Healthy participants were divided into two groups. Group 1 had light-coloured eyes (blue and green), and group 2 had dark-coloured eyes (brown). The main outcome measures were iris thickness, subfoveal choroidal thickness and nasal and temporal choroidal thicknesses 500 µm away from the fovea.

RESULTS

Group 1 comprised 31 subjects with light-coloured eyes, and group 2 had 31 subjects with dark eyes. The mean ages of groups 1 and 2 were 26.7 ± 7.5 years and 24.1 ± 5.8 years, respectively (p = 0.14). The choroidal thicknesses of the subfoveal, nasal and temporal regions were 336.3 ± 52.1 µm, 321.9 ± 43.6 µm and 318.4 ± 49.2 µm, respectively, in group 1 and 396.5 ± 76.9 µm, 372 ± 79.3 µm and 379.6 ± 82.4 µm, respectively, in group 2. All the values in group 1 were statistically lower than those in group 2 (p = 0.001, p = 0.001 and p = 0.003, respectively). The iris thickness in group 1 (493.73 ± 95.44 µm) was thinner than in group 2 (524.61 ± 69.74 µm) but not statistically significant (p = 0.141).

CONCLUSION

The results showed that a thinner choroid can be seen in disease-free light-coloured eyes. The iris colour should be considered among the factors affecting the choroidal thickness, such as age, sex, race and refractive error.

Vanishing pachy-choroid in pachychoroid neovasculopathy under long-term anti-vascular endothelial growth factor therapy

BACKGROUND

To investigate the diagnostic value of choroidal thickness in the definition of pachychoroid neovasculopathy (PNV), especially in eyes treated with anti-vascular endothelial growth factor (VEGF) therapy.

METHODS

Twenty-two consecutive eyes of 11 patients with uni- or bilateral PNV were analyzed. Anti-VEGF treatment was correlated with changes in choroidal thickness on enhanced depth imaging optical coherence tomography.

RESULTS

There were 14 eyes with PNV and 8 non-neovascular partner eyes. Mean age was 64.2 ± 4.0 (range: 60-72), total follow-up was 1.8 ± 0.4 (1-2) years. In PNV eyes, choroidal thickness at baseline was 400 ± 58 (269-485) μm. After two years and 13 anti-VEGF injections on average, a mean reduction of - 39 ± 10 (- 26 to - 56) % to final 241 ± 52 (162-327) μm was observed (p < 0.0001). Meanwhile, choroidal thickness in the partner eyes remained stable (p > 0.13 for all comparisons). A significant correlation of choroidal thinning and anti-VEGF injection rate was observed at year one (r = - 0.79; R2 = 0.63; p = 0.00073) and two (r = - 0.69; R2 = 0.48; p = 0.019). While 85.7% of PNV eyes exceeded a pachychoroid threshold of ≥350 μm at baseline, this figure dropped to 21.4% at year one and 0% at year two.

CONCLUSION

In PNV, choroidal thickness significantly decreases with anti-VEGF therapy, resembling a "vanishing pachy-choroid", and thus does not represent a valid long-term diagnostic criterium, especially when differentiating PNV from nAMD.

Diagnosis of central serous chorioretinopathy by deep learning analysis of en face images of choroidal vasculature: A pilot study

Purpose

To diagnose central serous chorioretinopathy (CSC) by deep learning (DL) analyses of en face images of the choroidal vasculature obtained by optical coherence tomography (OCT) and to analyze the regions of interest for the DL from heatmaps.

Methods

One-hundred eyes were studied; 53 eyes with CSC and 47 normal eyes. Volume scans of 12×12 mm square were obtained at the same time as the OCT angiographic (OCTA) scans (Plex Elite 9000 Swept-Source OCT^®, Zeiss). High-quality en face images of the choroidal vasculature of the segmentation slab of one-half of the subfoveal choroidal thickness were created for the analyses. The 100 en face images were divided into 80 for training and 20 for validation. Thus, we divided it into five groups of 20 eyes each, trained the remaining 80 eyes in each group, and then calculated the correct answer rate for each group by validation with 20 eyes. The Neural Network Console (NNC) developed by Sony and the Keras-Tensorflow backend developed by Google were used as the software for the classification with 16 layers of convolutional neural networks. The active region of the heatmap based on the feature quantity extracted by DL was also evaluated as the percentages with gradient-weighted class activation mapping implemented in Keras.

Results

The mean accuracy rate of the validation was 95% for NNC and 88% for Keras. This difference was not significant (P >0.1). The mean active region in the heatmap image was 12.5% in CSC eyes which was significantly lower than the 79.8% in normal eyes (P<0.01).

Conclusions

CSC can be automatically diagnosed by DL with high accuracy from en face images of the choroidal vasculature with different programs, convolutional layer structures, and small data sets. Heatmap analyses showed that the DL focused on the area occupied by the choroidal vessels and their uniformity. We conclude that DL can help in the diagnosis of CSC.

CHANGES IN SUBFOVEAL CHOROIDAL THICKNESS AFTER INTRAVITREAL DEXAMETHASONE IMPLANT THERAPY FOR DIABETIC MACULAR EDEMA

PURPOSE

To investigate changes in subfoveal choroidal thickness (SFCT) and their relationship with best-corrected visual acuity and optical coherence tomography parameters after intravitreal dexamethasone implant injection for diabetic macular edema.

METHODS

Eighty-one eyes treated with dexamethasone implant injection for diabetic macular edema were evaluated for best-corrected visual acuity, central macular thickness, SFCT, and optical coherence tomography parameters at baseline and Weeks 7 and 14.

RESULTS

The mean baseline SFCT significantly decreased at Weeks 7 (P < 0.001) and 14 (P < 0.001). At Week 7, each 1-µm reduction in central macular thickness and five Early Treatment Diabetic Retinopathy Study letters (-0.1 logarithm of the minimal angle of resolution) improvement were associated with SFCT reductions of 0.09 (P = 0.002) and 3.91 (P = 0.044) µm, respectively. At Week 14, each 1-µm reduction in central macular thickness was associated with a 0.14-µm reduction in SFCT (P < 0.001). Eyes with good functional and anatomical responses exhibited significantly greater SFCT reductions. Subretinal fluid resulted in greater SFCT changes (P = 0.039) and better best-corrected visual acuity (P = 0.033) at Week 7. A continuous ellipsoid zone/interdigitation zone layer was associated with a smaller mean SFCT at Week 7 (P = 0.002) and better best-corrected visual acuity at Weeks 7 and 14 (both, P < 0.001).

CONCLUSION

Changes in SFCT after dexamethasone implant injection therapy for diabetic macular edema may predict anatomical and functional outcomes and correlate with optical coherence tomography features that are known as predictors of treatment response.

Microstructural changes after half-dose photodynamic therapy in patients with chronic central serous chorioretinopathy

BACKGROUND

To evaluate the retinal and choroidal microstructural changes at fovea after half-dose photodynamic therapy (PDT) in patients with chronic central serous chorioretinopathy (CSC), using optical coherence tomography (OCT).

METHODS

The study included 35 eyes with unilateral chronic CSC treated with half-dose PDT. The foveal outer nuclear layer (ONL) and subfoveal choroidal thickness (SFCT) in the affected eyes were compared with baseline measurements at month 1, 3, and 6 after half-dose PDT, and those of the healthy contralateral eyes.

RESULTS

The mean baseline ONL thickness of the affected eyes was thinner compared to unaffected fellow eyes (66.9 ± 16.5 μm vs 111.5 ± 11.6 μm, p<0.001), and increased significantly to 68.6 ± 17.0 μm at month 3 and 68.9 ± 17.3 μm at month 6 after treatment (p = 0.025 and p = 0.014 respectively). The mean baseline SFCT of the affected eyes was thicker compared to unaffected fellow eyes (399.9 ± 87.0 μm vs 338.2 ± 75.4 μm, p<0.001), and decreased significantly after treatment at month 1, 3, and 6 (374.0 ± 84.8 μm, 369.7 ± 81.8 μm, 367.3 ± 80.8 μm respectively, p<0.001 for all). The responder group (n = 26), in which subretinal fluid was completely resorbed, showed a significant increase in ONL thickness and decrease in SFCT after treatment, whereas in the non-responder group (n = 9) ONL thickness and SFCT did not differ after treatment.

CONCLUSIONS

In CSC patients, significant changes are observed in foveal ONL thickness and SFCT after half-dose PDT. ONL thickness and SFCT are suggested to be considered in the OCT examinations of CSC patients.

Assessment of the choroidal structure in pregnant women in the first trimester

We investigated the anatomical differences in the choroidal structure between pregnant women in the first trimester of pregnancy and age-matched healthy nonpregnant women using enhanced depth imaging optical coherence tomography (EDI-OCT) and choroidal binarization analysis. The main parameters measured in the two study groups, namely, pregnant women in the first trimester and healthy nonpregnant women, were choroidal thickness and the choroidal luminal area. Binarization of the EDI-OCT images from each patient was performed, and the choroidal vascularity index (CVI) was calculated. The correlations between the baseline characteristics of the subjects and the CVI were investigated using linear mixed model analysis. As a result, there was no statistically significant difference in the mean age, best-corrected visual acuity, axial length, central retinal thickness, subfoveal choroidal thickness, systolic blood pressure (BP), or diastolic BP between the two study groups. Conversely, a significant difference was observed in the CVI (P = 0.012) between the two groups. The multivariate analysis identified a significant correlation between the CVI and the systolic BP (P = 0.0044, linear mixed test). Taken together, a larger choroidal luminal area was associated with a higher systolic BP, especially in the first trimester of pregnancy. Our findings may provide further insight into the choroidal changes that occur during pregnancy.

Central Serous Chorioretinopathy and Blood Serotonin Concentrations

BACKGROUND

To investigate blood serotonin (5-hydroxytryptamine (5-HT)) concentrations and their relationships with selected characteristics in patients with central serous chorioretinopathy (CSC).

METHODS

This was a prospective study including 93 patients with active CSC. Blood concentrations of 5-HT, adrenocorticotropic hormone, and cortisol were measured in patients with CSC. Selected patient characteristics, including disease history (acute or chronic), medication use, smoking history, mood status, best-corrected visual acuity (BCVA), subfoveal choroidal thickness (SCT), findings on fluorescein and indocyanine green angiography, and anatomical changes were evaluated during follow-up.

RESULTS

Eleven of the 93 patients had low 5-HT concentrations (<57 ng/mL) (12%, eight men and three women; mean age 55 years); we identified no significant relationship with acute/chronic disease status. The patients with low 5-HT were significantly more likely to have five or more fluorescein leakage sites (p = 0.0275), recurrence of subretinal fluids (p < 0.0001), and failure to achieve significant improvement in BCVA during follow-up (p = 0.862) than patients with 5-HT within the normal range.

CONCLUSIONS

Blood serotonin concentrations may influence the pathophysiology and prognosis of CSC.

A comparison of choroidal thicknesses between pachychoroid and normochoroid eyes acquired from wide-field swept-source OCT

PURPOSE

We investigated the wide-field choroidal thickness (CT) using swept-source optical coherence tomography (SS-OCT) and compared the characteristics of the choroidal layer between pachychoroid and normochoroid groups.

METHODS

A total of 120 eyes from 120 normal subjects were included. All subjects were divided into two groups according to the subfoveal CT (≥300 μm, pachychoroid group; <300μm, normochoroid group). All subjects underwent an HD spotlight 16 mm scan using SS-OCT. The CT was measured at the following 12 points: subfoveal, 3 points in the nasal peripapillary area, 6 points in the macular area and 2 peripheral points at 5400 and 8100 µm from the fovea. The CT measurements were compared between the two groups, and statistical analyses were performed to determine clinical factors associated with each point of the CT.

RESULTS

The CT in the pachychoroid group was thicker than that in the normochoroid group at all points (p < 0.01). The CTs of the two groups in the macular area were highly associated with the subfoveal CT. However, the CTs of the nasal peripapillary and peripheral areas showed lower associations with the subfoveal CT and lower diagnostic abilities for the pachychoroid group. The existence of pachyvessels was found to be a significant factor causing the regional variations.

CONCLUSIONS

The CTs in the peripapillary and peripheral areas showed different patterns than the subfoveal CT. Regional variations by pachyvessels were more frequent in the peripapillary and peripheral areas than in the macular area, and the subfoveal CT did not represent the whole choroidal area.

Evaluation of choroidal thickness and choroidal vascularity index during pregnancy

OBJECTIVE

To assess the choroidal structural characteristics in the first and third trimesters in pregnant women using enhanced depth imaging optical coherence tomography and binarization method.

DESIGN

Prospective study.

PARTICIPANTS

Twenty-five eyes of 25 pregnant women in the first trimester (group 1) and 25 eyes of 25 pregnant women in the third trimester (group 2) were examined. Healthy age-matched 25 participants were enrolled as a control group (group 3).

METHODS

The choroidal thickness (CT) was measured at 3 points; subfoveal, 1500 μm nasal to the fovea, and 1500 μm temporal to the fovea. Total choroidal area, luminal area, stromal area, stroma/lumen ratio, and choroidal vascularity index (CVI) were measured by Image-J software.

RESULTS

The mean subfoveal and nasal CT were statistically significantly increased in group 1 compared with controls (p = 0.005 and p = 0.004, respectively). The mean temporal CT was statistically significantly increased in group 1 compared with groups 2 and 3 (group 1 vs group 2, p = 0.043; group 1 vs group 3, p = 0.011). The mean total choroidal area, stromal area, and luminal area were significantly increased in groups 1 and 2 compared with control group (p < 0.001, p < 0.001, p < 0.001, and p < 0.001, p = 0.002, p = 0.002, respectively). There were no statistically significant differences among groups in terms of mean stroma/lumen ratio and CVI (p = 0.148 and p = 0.312, respectively).

CONCLUSIONS

There was a significant increase in subfoveal, temporal, and nasal CT in the first trimester. Total choroidal, stromal, and luminal areas were significantly increased in the first and third trimesters.

Central Serous Chorioretinopathy Classification

Central serous chorioretinopathy is characterized by an idiopathic neurosensory detachment of the retina. This narrative review aims to discuss the classification system used for central serous chorioretinopathy. Based on our current knowledge, there is no universally adopted classification system. This is the result of the unknown aspects related to pathogenesis and clinical spectrum and evolution. The best option could be to aggregate multimodal pieces of information alongside temporal and phenotypic characteristics.

Comparison of Retinal Layer Thickness and Capillary Vessel Density in the Patients with Spontaneously Resolved Acute Central Serous Chorioretinopathy

We investigate retinal layer thickness and capillary vessel density (VD) in the patients with central serous chorioretinopathy (CSC) who recovered spontaneously and evaluate the correlation between the changes in these values and visual outcomes using swept-source optical coherence tomography (SS-OCT) and OCT angiography (OCTA). This retrospective case–control study included 34 eyes of 34 patients with spontaneously resolved acute CSC. The changes in retinal layer thickness and capillary VD were examined using SS-OCT and OCTA after complete resolution of subretinal fluid (SRF). The fellow eyes and 34 healthy eyes were used as controls. In the eyes with CSC, the outer retinal layer was significantly thinner than in the eyes of fellow and healthy controls. The foveal avascular zone area and VDs in the superficial and deep capillary plexus in the eyes with CSC were not significantly different from those in the eyes of fellow and healthy controls. The VD of the choriocapillaris in the eyes with CSC was significantly lower than that in the eyes of fellow and healthy controls. Correlation analyses revealed that the outer retinal layer thickness and initial visual acuity were positively correlated with the final visual acuity. Furthermore, the initial SRF area and height were negatively correlated with the outer retinal layer thickness after SRF resolution. Attenuation of outer retinal layer thickness and decreased VD of the choriocapillaris were observed in the eyes with spontaneously resolved acute CSC. The outer retinal layer thickness could be an important visual predictor of CSC.

Clinical characteristics and visual outcomes of non-resolving subretinal fluid in neovascular AMD despite continuous monthly anti-VEGF injections: a long-term follow-up

PURPOSE

To describe the clinical characteristics and visual outcomes of neovascular age-related macular degeneration (NV-AMD) patients with irregular pigment epithelium detachment (PED) and non-resolving subretinal fluid (SRF) despite continuous monthly injections of anti-vascular endothelial growth factor (VEGF).

METHODS

This is a retrospective case series, including NV-AMD patients treated in a tertiary academic practice. Inclusion criteria were NV-AMD diagnosis, with irregular PED, and non-resolving SRF treated with continuous monthly anti-VEGF intravitreal injections. Data collection included best corrected visual acuity (BCVA), central macular thickness (CMT), sub-foveal choroidal thickness (SFCT), and type and location of PED as seen on optical coherence tomography (OCT).

RESULTS

A total of 738 patients with NV-AMD underwent anti-VEGF injections during the follow-up period and 20 eyes of 19 patients (14 females and 5 males) met the inclusion criteria. Average age was 81.7 ± 6.6 years, mean follow-up time was 32.1 ± 23.5 months, and mean number of injections was 31.3 ± 24.2. Mean VA was 0.26 ± 0.21 logMAR (Snellen 20/36) at baseline versus 0.20 ± 0.23 logMAR (Snellen 20/32) at the end of the follow-up (P = 0.28). All eyes presented with sub-foveal, type 1 macular neovascularization (MNV). Average sub-foveal choroidal thickness changed from 189.70 ± 68.46 μm at baseline to 169.00 ± 63.06 μm (P < 0.001) at last follow-up.

CONCLUSION

Patients with type 1 NV-AMD, irregular PED, and non-resolving SRF and under continuous treatment of monthly anti-VEGF injections may maintain good visual acuity after long period of time.

Is choroidal vascularity index a useful marker in different stages of idiopathic epiretinal membranes?

BACKGROUND

This study aims to evaluate the choroidal vascularity index in patients with idiopathic epiretinal membrane at different stages.

METHODS

This prospective study included 125 eyes of 125 patients with idiopathic epiretinal membrane and 62 eyes of 62 healthy control subjects. In this study, epiretinal membrane stages were defined based on the spectral-domain optical coherence tomography staging system. The choroidal vascularity index was measured as the ratio of the luminal area to the stromal area in the central 1500 μm after binarization on enhanced depth imaging optical coherence tomography images. Data on epiretinal membrane stages, choroidal vascularity index, and best-corrected visual acuity were noted.

RESULTS

Of 125 eyes with epiretinal membrane, 38 (30.4 %) had stage 1, 32 (25.6 %) had stage 2, and 55 (44 %) had stage 3 disease. Visual acuity was better in eyes with stage 1 or 2 epiretinal membrane than those with stage 3 epiretinal membrane (p < 0.001). The mean choroidal vascularity index was 2.29 ± 1.02 in the control, 2.23 ± 0.98 in the stage 1 epiretinal membrane, 2.22 ± 0.91 in the stage 2 epiretinal membrane, and 2.23 ± 1.11 in the stage 3 epiretinal membrane group. There was no significant difference between epiretinal membrane subgroups and the control group regarding the choroidal vascularity index (p = 0.81).

CONCLUSION

From the results obtained in the present study, the choroidal vascularity index was not effected by either the development or the progression of idiopathic epiretinal membrane.

Current Choroidal Imaging Findings in Central Serous Chorioretinopathy

Background: Central serous chorioretinopathy (CSCR) is a chorioretinal disease affecting mostly middle age males. It is marked by the serous detachment of the neurosensory layer at the macula. This review of the literature provides a framework of the current characteristic/relevant imaging findings of CSCR. Although the pathogenesis of CSCR is unclear, the choroid plays a major role and its changes are fundamental to the diagnosis and treatment of CSCR. Methods: A systematic literature search focusing on current multimodal imaging for CSCR was performed. Only articles reporting on original clinical data were selected, studies in a language other than English were included only if an English abstract was provided. Additional sources included articles cited in the references list of the first selected articles. We deduced imaging findings based on current and relevant literature on the topic. Results: We found that sub foveal choroidal thickness (SFCT) and choroidal vascularity index (CVI) were greater in eyes with acute CSCR than in eyes with chronic CSCR or normal eyes. There was increased choroidal thickness (CT) in the macula compared to peripapillary region. In healthy eyes, the highest CVI was found in the nasal region followed by the inferior, temporal, and superior quadrant. The area with the least CVI was the macula. In eyes with CSCR, 100% had asymmetric dominant vortex veins compared to 38% in normal eyes. Conclusion: Choroidal imaging has advanced the diagnosis of CSCR. This has led to numerous imaging biomarkers like CVI, CT, and hyper-reflective dots for early detection and possible prognostication of CSCR. More techniques like wide field scans and en face imaging are being employed to characterize the choroid in CSCR.

Biomarkers for central serous chorioretinopathy

Central serous chorioretinopathy (CSCR) is a common chorioretinal disease characterized by serous retinal detachment that most commonly involves the macular region. Although the natural history of the acute form shows a self-limiting course, a significant number of patients suffer from recurrent episodes leading to chronic disease, often leaving patients with residual visual impairment. Visual morbidity is often worsened by a delay in the diagnosis due to the incorrect understanding of the particular biomarkers of the disease. The aim of this review is to provide clinical understanding of the biomarkers of CSCR with an emphasis on the most recent findings in patient demographics, risk factors, clinical imaging findings, and management options. Patients with these biomarkers, age 30–44 years, male gender, increased stress levels, hypercortisolism (endogenous and exogenous exposures), sleep disturbance, pregnancy, and genetic predisposition have increased susceptibility to CSCR. Also, biomarkers on optical coherence tomography (OCT) such as choroidal thickness (CT) and choroidal vascularity index (CVI) showed good diagnostic and prognostic significance in the management of CSCR. There are nonspecific features of CSCR on OCT and OCT angiography such as choroidal neovascularization, photoreceptor alteration/cone density loss, and flat irregular pigment epithelium detachment. We described rare complications of CSCR such as cystoid macular edema (CME) and cystoid macular degeneration (CMD). Patients with CME recovered some vision when treated with anti-vascular endothelial growth factors (anti-VEGFs). Patients with CMD had irreversible macular damage even after treatment with anti-VEGFs.

Sensitivity and specificity of choroidal thickness measurement by EDI-OCT for central serous chorioretinopathy diagnosis

PURPOSE

To evaluate the utility of choroidal thickness (CT) measurement by enhanced depth imaging optical coherence tomography (EDI-OCT) for central serous chorioretinopathy (CSC) diagnosis.

METHODS

Cross-sectional comparative study of 62 consecutive patients: 38 with acute CSC and 24 with macular subretinal fluid from differential diagnoses (DD). Subfoveolar choroidal thickness was measured using EDI 9-mm horizontal protocol. We evaluated sensitivity, specificity and intraclass correlation coefficient.

RESULTS

Mean subfoveolar CT was greater in CSC group than in DD group (465.45 ± 115.42 μm vs. 347.54 ± 111.27 μm, p < 0.001). The best threshold measure was 390 μm in patients younger than 50 years giving a sensitivity of 89.7% (CI 95%: 73.6-100%) and a specificity of 75% (CI 95%: 40.9-87.3%). For patients older than 50 years best threshold measure was found at 400 μm giving a sensitivity of 45.5% (CI 95%: 21.3-72%) and a specificity of 80% (CI 95%: 58.4-91.9%). Intraclass correlation coefficient for CT measurement was 0.87 (CI 95%: 0.74-0.93).

CONCLUSION

CT measurement with EDI-OCT helps to differentiate CSC from other causes of macular subretinal fluid in patients younger than 50 years.

Keratoconus with Central Serous Chorioretinopathy: A Rare Combination

Keratoconus and central serous chorioretinopathy are two rare diseases. They can occur together in some individuals. We report a case of a 48-year-old man, who presented to our clinic with decreased visual acuity on his left eye. Physical examination, biomicroscopy, corneal topography, and optical coherence tomography revealed keratoconus and central serous chorioretinopathy. We discuss the possible connection between these two conditions.

Distinguishing Central Serous Chorioretinopathy From Neovascular Age-Related Macular Degeneration: A Prospective Study

Purpose:

This article identifies clinical features that differentiate central serous chorioretinopathy (CSR) from neovascular age-related macular degeneration (nAMD) and uses this information to develop a diagnostic tool.

Methods:

A prospective observational study was conducted of patients with a new diagnosis of CSR, nAMD, or indeterminate presentation. All patients underwent clinical assessment, axial length measurement, enhanced-depth imaging–optical coherence tomography, and intravenous fluorescein angiography. A final consensus diagnosis was derived following review of these factors.

Results:

A total of 56 eyes of 56 patients were enrolled (CSR = 34; nAMD = 22). The subfoveal choroidal thickness was greater in the CSR group (421 ± 106 µm) than the nAMD group (219 ± 91 µm, P < .001). The following odds ratio of CSR reached statistical significance: age 70 and younger (72.00, 95% CI: 11.99-432.50), subfoveal choroidal thickness greater than or equal to 300 µm (33.92, 95% CI: 4.06-283.18), dome-shaped neurosensory detachment (13.24, 95% CI: 3.22-54.45), retinal pigment epithelial changes (0.31, 95% CI: 0.10-0.97), subretinal hyperreflective material (0.11, 95% CI: 0.03-0.42), and fibrovascular pigment epithelial detachment (0.05, 95% CI: 0.01-0.47). A stepwise CSR vs nAMD clinical decision-making algorithm is proposed.

Conclusions:

Choroidal thickness is increased in CSR when compared with nAMD. The presented odds ratios and the CSR vs nAMD clinical decision-making tool can be applied to distinguish CSR from nAMD.

Characteristics of Pachychoroid Diseases and Age-Related Macular Degeneration: Multimodal Imaging and Genetic Backgrounds

The emergence of pachychoroid disease is changing the concept of age-related macular degeneration (AMD). The concept of pachychoroid diseases was developed through clinical observation of multimodal images of eyes with AMD and central serous chorioretinopathy; however, recent genetic studies have provided a proof of concept for pachychoroid spectrum disease, which should be differentiated from drusen-driven AMD. The genetic confirmation of pachychoroid concept further provides novel viewpoints to decode previously reported findings, which facilitates an understanding of the true nature of pachychoroid diseases and AMD. The purpose of this review was to elucidate the relationship between pachychoroid diseases and AMD by interpreting previous findings on pachychoroid diseases and AMD from the novel viewpoints of genetic associations. We confirmed that previous genetic studies supported the concept of pachychoroid diseases. From a genetic viewpoint, the presence of thick choroid and the presence of choroidal vascular hyperpermeability were important characteristics of pachychoroid spectrum diseases. Previous studies have also suggested the classification of polypoidal choroidal vasculopathy (PCV) into two subtypes, pachychoroid neovasculopathy and drusen-driven PCV. Genetic viewpoints will be beneficial to rearrange subtypes of drusen-driven AMD and pachychoroid spectrum diseases. Further genetic studies are needed to investigate pachyvessels, pachydrusen and the significance of polypoidal lesions in pachychoroid neovasculopathy and drusen-driven AMD/PCV.

Choroidal thickness estimation from colour fundus photographs by adaptive binarisation and deep learning, according to central serous chorioretinopathy status

This study was performed to estimate choroidal thickness by fundus photography, based on image processing and deep learning. Colour fundus photography and central choroidal thickness examinations were performed in 200 normal eyes and 200 eyes with central serous chorioretinopathy (CSC). Choroidal thickness under the fovea was measured using optical coherence tomography images. The adaptive binarisation method was used to delineate choroidal vessels within colour fundus photographs. Correlation coefficients were calculated between the choroidal vascular density (defined as the choroidal vasculature appearance index of the binarisation image) and choroidal thickness. The correlations between choroidal vasculature appearance index and choroidal thickness were −0.60 for normal eyes (p < 0.01) and −0.46 for eyes with CSC (p < 0.01). A deep convolutional neural network model was independently created and trained with augmented training data by K-Fold Cross Validation (K = 5). The correlation coefficients between the value predicted from the colour image and the true choroidal thickness were 0.68 for normal eyes (p < 0.01) and 0.48 for eyes with CSC (p < 0.01). Thus, choroidal thickness could be estimated from colour fundus photographs in both normal eyes and eyes with CSC, using imaging analysis and deep learning.

Visualization of Mouse Choroidal and Retinal Vasculature Using Fluorescent Tomato Lectin Perfusion

Purpose

To develop a reliable and simplified method to assess choroid and retinal vasculature on whole mount and cross sections in mice using tomato lectin (TL; Lycopersicon esculentum).

Methods

Albino mice (n = 27) received 1 mg/mL of TL (conjugated to Dylight-594) intravascularly through the tail vein, jugular vein, or cardiac left ventricle. Whole mounts of the retina and choroid were evaluated using fluorescence microscopy. Perfusion with GSL-IB4 conjugated to Dylight-594 and fluorescein isothiocyanate was performed to compare against labeling with TL. Co-labeling of choroidal endothelial cells with perfused TL on cross-sections with antibodies directed against the choriocapillaris-restricted endothelial cell marker CA4 was performed. The percentage of perfused choroidal and retinal vessels was assessed semiquantitatively. One mouse was subjected to thermal laser damage before perfusion to cause retinal and choroidal vasculature ablation.

Results

Intravascular injection of TL led to consistent, robust labeling of retinal and choroidal vascular walls. On cross-sections, choriocapillaris was co-labeled with CA4 and TL. On flat mount, TL perfusion resulted in better labeling of choroidal vessels using tail/jugular vein injection compared with cardiac perfusion (P < .01). More consistent labeling of the choroidal and retinal vascular trees was observed with TL than with GSL-IB4. Vascular damage caused by laser ablation was detected readily using this method.

Conclusions

TL injection intravascularly can reliably label normal and ablated choroid and retinal vasculature in mouse in a quick, simple manner.

Translational Relevance

These data will help to facilitate modeling in rodents for diseases such as age-related macular degeneration, diabetes, and other ischemic/angiogenic processes that can also be used for treatment evaluation.

Correlation of retinal changes with choroidal changes in acute and recurrent central serous chorioretinopathy assessed by swept-source optical coherence tomography

Purpose

To evaluate affected choroidal regions and corresponding retinal changes in acute and recurrent central serous chorioretinopathy using swept-source optical coherence tomography.

Methods

The foveal and subfoveal choroidal thicknesses were measured with swept-source optical coherence tomography. The retina was divided into five zones on the swept-source optical coherence tomography image based on baseline choroidal thickness being <100, 100-199, 200-299, 300-399 and ⩾400 μm. The retinal and choroidal thicknesses in the same five regions were evaluated during follow-up. The measurements were then compared between baseline (when central serous chorioretinopathy was active) and follow-up (after complete resolution of disease).

Results

At baseline, in the acute group, the mean outer retinal layer thickness was significantly higher in areas with thicker choroid and lower in areas with thinner choroid. No such change was noticed in the recurrent group. In the acute group, the overall retinal thickness from baseline to follow-up decreased from 269.84 to 251.9 µm, ganglion cell layer thickness decreased from 107.14 to 101.28 µm, retinal nerve fibre layer thickness decreased from 56.96 to 49.33 µm, and no significant difference was noted in choroidal thickness. In the recurrent group, choroidal thickness significantly increased from 254.58 to 262.55 µm and ganglion cell layer decreased from 103.43 to 94.01 µm. No significant difference was noted in overall retina and retinal nerve fibre layer. Reduction in choroidal and retinal layer thicknesses was better in eyes which underwent laser treatment than the observation group.

Conclusion

Swept-source optical coherence tomography might serve as an important non-invasive tool for both evaluating the extent of pathology and to predict the recurrence rate.

OCTA characterisation of microvascular retinal alterations in patients with central serous chorioretinopathy

PURPOSE

This study aimed to describe the characteristics of microvascular retinal alterations in eyes with chronic central serous chorioretinopathy (CSC) employing optical coherence tomography angiography (OCTA) analysis.

METHODS

We collected data from 472 eyes with chronic CSC from 336 patients who had OCTA obtained. Each OCTA image was graded by two readers to assess the presence of microvascular retinal alterations, including regions of vascular rarefaction/retinal hypoperfusion, enlargement of the foveal avascular zone (FAZ) and presence of telangiectasias or microaneurysms. Volume spectral domain optical coherence tomography (SD-OCT) scans were obtained through the macula and the OCT was correlated with the OCTA findings in eyes with retinal vascular alterations.

RESULTS

OCTA displayed microvascular retinal alterations in 18 out of 474 eyes (3.6%) from 14 patients (13 male and 1 female; mean±SD age was 54.7±11.1 years). One eye displayed the presence of retinal telangiectasias, while 17 out of 18 eyes were graded as having areas of retinal vascular rarefactions, and 3 out of 17 eyes were also characterised by an enlargement of the FAZ. The parafoveal region was the location most involved by retinal vascular changes (66,7%), followed by foveal (22,2%) and perifoveal (11.1%) regions, respectively.

CONCLUSION

Although CSC is known to represent a choroidal disorder, retinal vascular alterations may be present in these eyes and OCTA may represent a useful tool to identify and describe them.

Analysis of Choroidal Vascularity Index in Keratoconus Patients Using Swept-Source Optical Coherence Tomography-Based Binarization Techniques

PURPOSE

To analyse the vascular density of the choroid in a keratoconus (KC) population using swept-source optical coherence tomography (SS-OCT).

METHODS

Prospective, noninterventional study that analysed 97 eyes from 52 KC patients and 145 eyes from 89 healthy controls. The sample was divided in four different age groups. Inclusion criteria were topographic diagnosis of KC using Pentacam, axial length shorter than 26 mm, good quality of the images, and no other systemic or ocular diseases. A 12 mm horizontal single-line SS-OCT b-scan was performed to create a choroidal thickness (CT) profile. Validated automated segmentation and binarization were used in order to analyse choroidal, stromal, and vascular areas.

RESULTS

The percentage of choroidal vascularity (vascular area/total area) was 56.6% in KC patients vs. 49.4% in controls. Aged-adjusted choroidal, stromal, and vascular areas and corrected choroidal percentage of vascularity are statistically increased in KC patients when compared with healthy controls (p < 0.001). All these parameters show a decreasing trend with age. Both stromal and vascular areas were thicker in KC patients (p < 0.001).

CONCLUSIONS

Choroidal, stromal, and vascular areas and corrected choroidal percentage of vascularity are statistically increased in KC patients when compared with healthy controls. All these parameters tend to decrease with age.

Evaluation of the choroidal features in pachychoroid spectrum diseases by optical coherence tomography and optical coherence tomography angiography

PURPOSE

To evaluate choroidal area, stroma/lumen ratio, choriocapillaris vessel density, and choriocapillaris flow area in eyes with central serous chorioretinopathy, uncomplicated pachychoroid, and pachychoroid pigment epitheliopathy using enhanced depth imaging-optical coherence tomography and optical coherence tomography angiography.

MATERIALS AND METHODS

This retrospective study analyzed enhanced depth imaging-optical coherence tomography and optical coherence tomography angiography scans of 142 eyes of 92 patients with central serous chorioretinopathy, uncomplicated pachychoroid, and pachychoroid pigment epitheliopathy. The choroidal area and stroma/lumen ratio were measured by binarization of enhanced depth imaging-optical coherence tomography images. Choriocapillaris vessel density and choriocapillaris flow area were measured at the choriocapillaris level by manual segmentation of optical coherence tomography angiography scans.

RESULTS

The mean stroma/lumen ratio results were 0.361, 0.345, and 0.354 in central serous chorioretinopathy, uncomplicated pachychoroid, and pachychoroid pigment epitheliopathy groups, respectively (p > 0.05). The mean whole image choriocapillaris vessel density in uncomplicated pachychoroid group was higher compared with central serous chorioretinopathy and pachychoroid pigment epitheliopathy groups (p < 0.0001). The mean foveal, parafoveal, and perifoveal choriocapillaris vessel densities were lower in central serous chorioretinopathy group than in uncomplicated pachychoroid group (p < 0.0001). The mean choriocapillaris flow area was lower in central serous chorioretinopathy group than in uncomplicated pachychoroid and pachychoroid pigment epitheliopathy groups (p < 0.0001 and p = 0.01, respectively).

CONCLUSION

Our findings suggest that both choroidal vessels and stroma are equally involved in central serous chorioretinopathy, uncomplicated pachychoroid, and pachychoroid pigment epitheliopathy. The choriocapillaris segment seems to be more affected in central serous chorioretinopathy compared to uncomplicated pachychoroid and pachychoroid pigment epitheliopathy. However, the reduced optical coherence tomography angiography signal in central serous chorioretinopathy group could be due to shadowing artifact or choriocapillaris hypoperfusion and further studies with higher quality imaging tools are needed.