Features of abnormal choroidal circulation in central serous chorioretinopathy

Research Progress of Central Serous Chorioretinopathy in Recent 20 Years Based on Visual Bibliometric Analysis

OBJECTIVE

To dynamically track the publications on central serous chorioretinopathy (CSC) and depict the research status and hot spots to guide future research.

METHODS

Gather all papers published in this area between 2004 and 2024 in the WOSCC databases comprehensively, assess their trends, and characterize the contributions of various nations, authors, institutions, and journals. In addition, VOSviewer, CiteSpace, and R software are used to obtain the most popular keywords for the topic.

RESULTS

A total of 2,203 papers were published across 1,863 institutions in 59 countries. Among these, 6,907 authors contributed to publications in 300 journals and generated a total of 35,638 citations. The number of publications continues to grow steadily. Notably, Jay Chhablani's team/Lab stands out as the leading contributor with ownership of 84 publications. Through keyword network analysis and clustering techniques, risk factor-related clustering, imaging-related clustering, pathogenesis-related clustering, and treatment-related clustering were identified. Furthermore, keyword analysis has unveiled emerging frontier areas including pachychoroid disease, choroidal vasculature abnormalities, PDT therapy, and optical coherence tomography that have garnered increasing interest.

CONCLUSION

This study presents a comprehensive review of central serous retinopathy research conducted in the past two decades, highlighting key trends and exploring emerging research frontiers within this field. As such, it provides valuable references and suggestions for researchers engaged in studying this topic.

Choroidal venous overload in Vogt‒Koyanagi‒Harada disease

BACKGROUND/OBJECTIVES

This study aimed to investigate the change of choroidal venous overload in Vogt‒Koyanagi‒Harada (VKH) disease. Clinical records of 52 patients with VKH disease (52 eyes) and 24 control subjects (24 eyes) who underwent multimodal imaging, including fluorescein angiography (FA) and indocyanine green angiography (ICGA), were retrospectively reviewed.

SUBJECTS/METHODS

Imaging data were assessed for signs associated with choroidal venous overload, e.g., choroidal perfusion delay, choroidal vascular hyperpermeability, dilated choroidal veins, and intervortex venous anastomosis (IVA). Dual FA and ICGA scoring for active posterior segment inflammation was performed. Clinical and imaging features associated with choroidal venous overload were compared between early- and late-stage VKH disease.

RESULTS

Choroidal perfusion delay, choroidal vascular hyperpermeability, dilated choroidal veins, and IVA were more prevalent in eyes with VKH disease (69.2%, 67.3%, 61.5%, and 65.4%, respectively) than in control eyes (25.0%, 20.8%, 25.0%, and 37.5%, respectively) (p < 0.05). All eyes with IVA in the early-stage of VKH disease had got other 3 signs. All choroidal venous overload signs were more prevalent in patients with early-stage (20 eyes) than in those with late-stage VKH disease (32 eyes) (p < 0.05). The number of choroidal venous overload signs were inversely related to disease duration (p < 0.001) and proportionally related to the total ICGA score (p < 0.001). IVA was significantly associated with the total ICGA score in logistic regression (p = 0.014).

CONCLUSIONS

Choroidal venous overload occurs early in VKH disease. Angiographic signs of choroidal venous overload may be useful markers to assess the status of VKH disease.

Evaluation of carotid intima-media thickness measurements in patients with central serous chorioretinopathy

BACKGROUND

Central serous chorioretinopathy (CSC) is a systemic disease more than a disease localized to the eye, and there may be vascular involvement in its pathogenesis.

OBJECTIVE

This study aimed to evaluate the carotid intima-media thickness (IMT) of patients with CSC, to compare it with that of healthy individuals, and to explore whether there might be an association between CSC and subclinical carotid atherosclerotic disease.

MATERIALS AND METHODS

Adult patients with CSC (n = 30) and healthy individuals (n = 30) were included in this prospective study. All participants underwent complete ophthalmologic imaging and were then referred to the radiology department. Carotid IMT measurements were performed using ultrasound imaging. Measurements of the two groups were obtained and compared.

RESULTS

There was no statistically significant difference between patients with CSC and the control group with respect to age, gender, and smoking habits. The mean (±standard deviation, SD) carotid IMT values obtained by ultrasound measurements for the right and left sides in the patient group were 0.71 mm (± 0.19) and 0.71 mm (± 0.21), respectively. The mean (±SD) carotid IMT values for the right and left sides in the control group were 0.61 mm (± 0.15) and 0.60 mm (± 0.15), respectively. The mean carotid IMT values in the patient group were significantly higher than those in the control group for the right and left sides (p = 0.02 and p = 0.03, respectively).

CONCLUSION

Carotid IMT is increased in patients with CSC compared to healthy individuals. This outcome might reinforce the benefit of carotid artery screening following diagnosis of CSC by ophthalmologists for early detection of subclinical carotid atherosclerotic disease.

Central Serous Chorioretinopathy: An Update on the Current State of Management

Central serous chorioretinopathy (CSCR) is a relatively common retinal disorder that leads to central vision impairment, often with a high recurrence rate. The exact etiology and pathogenetic mechanisms have not been fully elucidated but are likely to be associated with hyperpermeability of the choroidal capillaries and failure of the retinal pigment epithelium (RPE), leading to serous detachment of the neurosensory retina. Multimodal imaging plays a critical role in the diagnostic approach and monitoring of CSCR. Fortunately, the natural course of the disease is usually self-limiting, with spontaneous resolution and total fluid reabsorption. However, some patients may exhibit recurrences or persistent subretinal fluid (chronic CSCR), leading to progressive and irreversible RPE atrophy or photoreceptor damage. Thus, to prevent permanent visual loss, individualized treatment should be considered. Recent developments in the diagnostic and therapeutic approach have contributed to better outcomes in patients with CSCR. More studies are required to improve our understanding of epidemiology, pathogenesis, diagnosis, and treatment, with a significant impact on the management of this challenging clinical entity. The purpose of this review is to summarize the current knowledge about the clinical features, diagnostic workup, and therapeutic approach of CSCR.

Foveal atrophy in patients with active central serous chorioretinopathy at first presentation: characteristics and treatment outcomes

BACKGROUND/AIMS

This study aimed to investigate the clinical characteristics and treatment outcomes of patients with active central serous chorioretinopathy (CSC) and foveal atrophy.

METHODS

Patients diagnosed with active idiopathic CSC using multimodal imaging and followed up for at least 6 months were included. They were divided into two groups (foveal atrophy group vs foveal non-atrophy group) according to a cut-off central foveal thickness of 120 µm on baseline optical coherence tomography (OCT). Baseline characteristics, angiographic and tomographic features and treatment outcomes were compared between the two groups.

RESULTS

Of the 463 patients, 92 eyes of 92 patients (19.9%) were in the foveal atrophy group and 371 eyes of 371 patients (80.1%) were in the foveal non-atrophy group. The baseline subretinal fluid (SRF) height was 111.3±76.8 µm in the foveal atrophy group and 205.0±104.4 µm in the foveal non-atrophy group on OCT images (p<0.001). Complete resolution of SRF after treatment was noted in 60.4% and 93.5% of patients in the foveal atrophy and foveal non-atrophy groups at the final visit, respectively (p<0.001). The foveal atrophy group showed worse visual acuity at baseline (logarithm of the minimum angle of resolution, 0.43±0.33 vs 0.13±0.18, p<0.001) and final visit (0.41±0.32 vs 0.05±0.15, p=0.035).

CONCLUSIONS

CSC with foveal atrophy was associated with a shallow SRF height, low treatment efficacy and poor vision before and after treatment. We suggest that early active treatment should be considered for eyes with CSC accompanied by a persistent shallow SRF and foveal atrophy.

Optical coherence tomography choroidal enhancement using generative deep learning

Spectral-domain optical coherence tomography (SDOCT) is the gold standard of imaging the eye in clinics. Penetration depth with such devices is, however, limited and visualization of the choroid, which is essential for diagnosing chorioretinal disease, remains limited. Whereas swept-source OCT (SSOCT) devices allow for visualization of the choroid these instruments are expensive and availability in praxis is limited. We present an artificial intelligence (AI)-based solution to enhance the visualization of the choroid in OCT scans and allow for quantitative measurements of choroidal metrics using generative deep learning (DL). Synthetically enhanced SDOCT B-scans with improved choroidal visibility were generated, leveraging matching images to learn deep anatomical features during the training. Using a single-center tertiary eye care institution cohort comprising a total of 362 SDOCT-SSOCT paired subjects, we trained our model with 150,784 images from 410 healthy, 192 glaucoma, and 133 diabetic retinopathy eyes. An independent external test dataset of 37,376 images from 146 eyes was deployed to assess the authenticity and quality of the synthetically enhanced SDOCT images. Experts' ability to differentiate real versus synthetic images was poor (47.5% accuracy). Measurements of choroidal thickness, area, volume, and vascularity index, from the reference SSOCT and synthetically enhanced SDOCT, showed high Pearson's correlations of 0.97 [95% CI: 0.96-0.98], 0.97 [0.95-0.98], 0.95 [0.92-0.98], and 0.87 [0.83-0.91], with intra-class correlation values of 0.99 [0.98-0.99], 0.98 [0.98-0.99], and 0.95 [0.96-0.98], 0.93 [0.91-0.95], respectively. Thus, our DL generative model successfully generated realistic enhanced SDOCT data that is indistinguishable from SSOCT images providing improved visualization of the choroid. This technology enabled accurate measurements of choroidal metrics previously limited by the imaging depth constraints of SDOCT. The findings open new possibilities for utilizing affordable SDOCT devices in studying the choroid in both healthy and pathological conditions.

Ink blot leakage in central retinal artery occlusion

PURPOSE

To describe a typical case of acute central retinal artery occlusion (CRAO) with an ink-blot pattern of hyperfluorescent leak on fundus fluorescein angiography (FFA).

CASE DESCRIPTION

A 21-year-old woman came to the clinic with one day of painless right eye vision loss. Her right eye had finger counting at ½ meter. Her right eye had a relative afferent pupillary defect, but her anterior segment and intraocular pressure of both eyes were normal.

RESULTS

The right eye fundus showed signs of acute CRAO with severe grade on optical coherence tomography (OCT). FFA imaging showed a mid-phase hyperfluorescent leak that persisted until the late stage. OCT scan through the hyperfluorescent spot showed absence of neurosensory detachment with normal retinal pigment epithelium, ruling out a central serous chorioretinopathy (CSCR). Ocular massage and anterior chamber paracentesis were performed. At the 10-day follow-up, the patient's visual acuity was counting fingers at ½ meter, and the OCT scan showed findings of CRAO chronicity. The hyperfluorescent spot disappeared on the subsequent FFA.

CONCLUSION

We report a case of ink-blot leakage on FFA, similar to that observed in CSCR in an eye with acute CRAO. We propose that the hyperfluorescent spot in our acute CRAO was likely caused by red blood cell aggregation or rouleaux formation.

Chronic Central Serous Chorioretinopathy in Elderly Subjects: Structure and Blood Flow Characteristics of Retina and Choroid

INTRODUCTION

With advancements in imaging technology, researchers have been able to identify more distinctive imaging features of central serous chorioretinopathy (CSC). However, existing research primarily concentrates on young patients aged 50 years and below, leaving a dearth of studies on elderly CSC patients. Previous studies indicate that elderly CSC patients may exhibit unique imaging characteristics and have a clinical prognosis that significantly differs from younger patients. This study aimed to evaluate the characteristics of retina, choroid structure, and blood flow in elderly patients with chronic CSC (cCSC) examined multimode imaging and try to find new pathogenesis information of it.

METHODS

Using a cut-off age of 50 years, patients with chronic central serous chorioretinopathy were divided into two groups: older and younger. The control group consisted of 40 healthy individuals, with their right eyes assigned. Various clinical features were recorded, including the incidence of ellipsoid zone rupture (EZ-), fibrin in the subretinal fluid (SRF), pachydrusen, subretinal drusenoid deposits (SDD), pigment epithelial detachment (PED), double-layer sign (DLS), and choroidal lipid globule cavern. Measurements were taken for the thickness of the outer nuclear layer (ONL), the length of the extended outer photoreceptor segment (POS), the height and width of SRF, the vascular density of each layer of the retinal capillary plexus, the central macular thickness (CMT), and the subfoveal choroidal thickness (SFCT).

RESULTS

The proportion of females in the elderly group (43.75%) was significantly higher than that in the youth group (22.41%) (p = 0.034). The degree of hyperopia in the elderly group (1.03 ± 0.73) was higher than that in the youth group (0.26 ± 1.06), with a significant difference in BCVA (p = 0.05). The thickness of SFCT, CMT, ONL in the elderly group, and the length of photoreceptor outer segment in the elderly group were thinner than those in the youth group (p < 0.05). Choroidal capillary perfusion area (CCPA), macular area, and paramacular area were lower in the elderly group than those in the youth group in the full scan range (p < 0.05). The blood flow densities of deep capillary plexus (DCP), intermediate capillary plexus (ICP), and superficial capillary plexus (SCP) in the whole scan range, macular area, and paramacular area were lower in the elderly group than in the youth group, but the differences were not statistically significant.

CONCLUSIONS

In conclusion, our data suggest that elderly patients with cCSC may experience different disease outcomes. Elderly cCSC patients exhibit less gender bias, poorer vision, more severe structural damage and ischemia in the choroid and retina, and have a higher risk of developing choroidal neovascularization.

Long-term visual outcomes in pachychoroid spectrum diseases and its associating factors of eyes with chronic central serous chorioretinopathy

To analyze the long-term visual outcomes of pachychoroid spectrum diseases (PSD). Retrospective study. We reviewed the medical charts of consecutive patients with PSD, including focal choroidal excavation (FCE), pachychoroid pigment epitheliopathy (PPE), central serous chorioretinopathy (CSC), and pachychoroid neovasculopathy (PNV). The patients initially visited the Tokyo University Hospital from January 2008 to March 2021. Survival analyses were performed, in which loss of vision was defined as visual acuity (VA) of 0.2 logarithm of minimal angle of resolution (logMAR) or worse, 0.5 logMAR or worse, or VA worsening by 0.3 logMAR or greater. Moreover, we further investigated factors associated with visual prognosis, particularly in the CSC group. A total of 741 eyes of 638 patients were included in this analysis. The CSC or PNV group showed significantly worse visual prognosis than the FCE&PPE group for VA to 0.2 logMAR or worse (P = 0.0117 or 0.0001, respectively) and for VA worsening by 0.3 logMAR or greater (P = 0.0283 or 0.0037, respectively). In the CSC group, unlike age, sex, or treatment history, the accumulative duration of subfoveal fluid existence ≥ 12 months (continuous or intermittent) was significantly associated with visual prognosis (P < 0.0001). Among PSD, CSC and PNV were associated with a higher risk of vision loss in the long term than FCE and PPE. The duration of subretinal fluid existence was identified as a significant factor affecting long-term visual outcomes in CSC.

Increased risk of glaucoma development in patients with central serous chorioretinopathy: results of a 11-year population-based cohort study

PURPOSE

To investigate whether patients with central serous chorioretinopathy (CSC) have increased risk of developing glaucoma.

METHODS

Patients diagnosed with CSC between 1 January 2008 and 31 December 2018 were included in this study using data from the Taiwanese National Health Insurance Research Database (NHIRD). The CSC cohort was matched with a non-CSC cohort using the propensity score matching method, based on sex, age (in 10-year intervals), index date year, comorbidities, and steroid use, resulting in equal numbers of patients in both cohorts. Patients were followed up until 31 December 2019 or until they were withdrawn from the NHIRD. The incidence of glaucoma was compared between the two cohorts using the Cox regression model, and the risk of developing glaucoma was estimated using the Kaplan-Meier method.

RESULTS

After adjusting for sex, age, comorbidities, and steroid use, the CSC cohort showed a significantly higher risk of developing glaucoma compared to those without CSC (adjusted HR = 3.99; 95% CI = 3.44-4.62). The cumulative incidence of glaucoma in the CSC cohort was also significantly higher than in the non-CSC cohort (log-rank test, p < 0.001). Among the glaucoma subtypes, normal tension glaucoma had the highest risk (adjusted HR = 5.79; 95% CI = 3.41-9.85), followed by primary open-angle glaucoma (adjusted HR = 2.77; 95% CI = 2.12-3.62).

CONCLUSIONS

In conclusion, our study shows that CSC patients are at a higher risk of developing glaucoma, especially NTG. Awareness and regular glaucoma screenings are essential for patients with CSC.

INDOCYANINE GREEN ANGIOGRAPHY OF TYPE 1 MACULAR NEOVASCULARIZATION IN AGE-RELATED MACULAR DEGENERATION AND CENTRAL SEROUS CHORIORETINOPATHY REVEALS DIFFERENT DISEASE MECHANISMS

PURPOSE

To assess the rate of late phase hyperfluorescent plaque (LPHP) in Type 1 macular neovascularization (MNV) in central serous chorioretinopathy (CSCR) and age-related macular degeneration (AMD) and to evaluate its prognostic value.

METHODS

Retrospective study including Type 1 MNV in AMD and CSCR, from 2012 to 2020. Eyes with a late indocyanine green angiography image (>20 minutes) and clear visualization of MNV on optical coherence tomography angiography (OCTA) were included. Quantitative and qualitative parameters on optical coherence tomography and best-corrected visual acuity were recorded at baseline and after three monthly antivascular endothelial growth factor injections.

RESULTS

Eighty-three eyes were included, 35 with CSCR and 48 with AMD. Patients in the CSCR group were significantly younger than in the AMD group (61.3 ± 10.4 vs. 80.2 ± 6.8 years, respectively, P < 0.001), predominantly male (68.6% CSCR vs. 35.4% AMD; P = 0.003), and with a thicker choroid (379 ± 93.3 µ m vs. 204.2 ± 93.2 µ m; P < 0.001). Type 1 MNV in CSCR showed fewer LPHP compared with AMD (31.4% vs. 77.1%; P < 0.001). The baseline visual acuity was lower in patients with LPHP (0.37 ± 0.22 vs. 0.27 ± 0.28 logarithm of the minimum angle of resolution, P = 0.03). On multivariate analysis, AMD was associated with the presence of LPHP ( P < 0.001). No significant difference in the response to antivascular endothelial growth factor was observed.

CONCLUSION

Leakage of macromolecules from MNV and accumulation in the retinal pigment epithelium and/or in the stroma imaged by the LPHP is less common in eyes with Type 1 MNV in CSCR than in AMD. Late phase indocyanine green angiography imaging offers an insight into the metabolism of the dye and the environment surrounding the neovascular membrane.

Central Serous Chorioretinopathy by Autofluorescence, Enface and SLO-Retromode Imaging

The aim of our study was to investigate the clinical features of central serous chorioretinopathy (CSC) with autofluorescence (AF), retromode (RM), and enface imaging. This retrospective study was conducted at Fondazione Policlinico Universitario A. Gemelli, IRCCS, Rome (Italy), between September and December 2022. Each patient underwent a complete ophthalmological examination, which included optical coherence tomography (OCT), enface image analysis, AF, and RM imaging. We further evaluated the presence and area of extension of serous retinal detachment and retinal pigment epithelium (RPE) atrophy through AF, RM, and enface imaging. We included 32 eyes from 27 patients (mean age: 52.7 ± 13.3 years). The median AF area was 19.5 mm² (IQR 6.1-29.3), while the median RM area was 12.3 mm² (IQR 8.1-30.8), and the median enface area was 9.3 mm² (IQR 4.8-18.6). RPE atrophy was diagnosed in 26 cases (81.3%) with RM imaging and in 75% of cases with AF. No difference emerged between AF and RM analysis in the detection of central serous detachment in CSC. However, RM imaging showed a high specificity (91.7%) and negative predictive value (84.6%) to detect RPE changes when compared to the AF standard-of-care technique. Thus, RM imaging could be considered an adjunctive imaging method in CSC.

URINARY METABOLOMICS OF CENTRAL SEROUS CHORIORETINOPATHY

PURPOSE

To analyze the urinary metabolomic profile of central serous chorioretinopathy cases.

METHODS

In a cross-sectional study, 80 participants with central serous chorioretinopathy were compared with 80 age-matched and sex-matched controls. Urinary metabolites were measured using Metabolon's Discovery HD4 platform.

RESULTS

Of 1,031 metabolites total that were measured in urine samples, 53 were upregulated and 27 downregulated in central serous chorioretinopathy participants compared with controls. After exclusion of potentially confounding xenobiotics and bile compounds that could represent digestive processes, 14 metabolites were significantly higher and 12 metabolites were significantly lower in cases compared with controls. One upregulated metabolite (tetrahydrocortisol sulfate) is involved in the corticosteroid subpathway. The downregulated metabolites are unrelated to the identified corticosteroid subpathway.

CONCLUSION

The upregulation of urinary tetrahydrocortisol sulfate in central serous chorioretinopathy cases provides a precise molecular basis to further study the role of corticosteroids in producing choroidal venous congestion.

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.

Central serous chorioretinopathy: Pathophysiology, systemic associations, and a novel etiological classification

Central serous chorioretinopathy (CSC) has remained an enigmatic disease since its initial description by Von Graefe. Over the years, multiple risk factors have been recognized: these include psychological stress, behavioral traits, and corticosteroids. The basic pathophysiology of CSC involves choroidal thickening, vascular congestion, altered choroidal blood flow (ChBF), and choroidal hyperpermeability, leading to retinal pigment epithelium decompensation and subsequent neurosensory detachment. Multiple organ systems, mainly the nervous, cardiovascular, endocrinal, and renal systems participate in the control of the vascular tone and the ChBF via hypothalamus-pituitary-adrenal axis and renin-angiotensin-aldosterone system, while others such as the hepatic system regulate the enzymatic degradation of corticosteroids. Many vasoactive and psychotropic drugs also modulate the ocular perfusion. In addition, there are anatomical and genetic predispositions that determine its progression to the chronic or recurrent form, through cellular response and angiogenesis. We herein review the basic pathophysiology and immunogenetics in CSC along with the role of multiple organ systems. With this background, we propose an etiological classification that should provide a framework for customized therapeutic interventions.

Comparison of swept-source OCTA and indocyanine green angiography in central serous chorioretinopathy

Background

To compare swept-source optical coherence tomography angiography (SS-OCTA) and indocyanine green angiography (ICGA) in patients with central serous chorioretinopathy (CSC).

Methods

SS-OCTA and ICGA images of 39 eyes with symptomatic CSC were collected and aligned. Spatial overlap of the annotations of the coarse granulated high reflective area on choriocapillary OCTA and the hyperfluorescence area on mid-phase ICGA was calculated according to the Jaccard index (JI). SS-OCTA findings of fellow eyes and changes in SS-OCTA abnormalities during the follow-up were also analyzed.

Results

Three main types of abnormalities in choriocapillaris SS-OCTA images were found: type A, coarse granulated high reflective area (39 eyes [100%]); type B, roundish dark halo around Type A (32 eyes [82.1%]); and type C, coarse granulated low reflective area (39 eyes [100%]). The mean JI of type A on SS-OCTA and the hyperfluorescence area on ICGA were 0.55 ± 0.15 for grader 1 and 0.49 ± 0.15 for grader 2. The mean area of type A abnormalities on SS-OCTA and hyperfluorescence on ICGA was 3.976 (IQR, 2.139–8.168) and 3.043 (IQR, 1.408–4.909) mm² (P = 0.199). The areas of type A, B and C abnormalities on SS-OCTA after laser treatment or observation were 3.36mm² (IQR, 2.399–9.312), 2.9mm² (IQR, 2.15–3.7), and 0.19mm² (IQR, 0.08–0.23), respectively, which was smaller than those in the baseline (7.311mm² (IQR 3.788–11.209), P < 0.001; 4.3mm² (IQR, 2.8–9.8), P = 0.002;0.33mm² (IQR, 0.23–0.38), P < 0.001). The change in the type A, B or C area was not significantly different between the two groups (P = 0.679, 0.732, and 0.892).

Conclusion

The coarse granulated high reflective area in SS-OCTA corresponded well with the hyperpermeability area in ICGA. SS-OCTA promotes noninvasive visualization and follow-up quantifications of the choroidal vasculature in CSC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-022-02607-4.

Imaging-based Assessment of Choriocapillaris: A Comprehensive Review

PURPOSE

Over the past two decades, advancements in imaging modalities have significantly evolved the diagnosis and management of retinal diseases. Through these novel platforms, we have developed a deeper understanding of the anatomy of the choroidal vasculature and the choriocapillaris. The recently developed tools such as optical coherence tomography (OCT) and OCT angiography (OCTA) have helped elucidate the pathological mechanisms of several posterior segment diseases. In this review, we have explained the anatomy of the choriocapillaris and its close relationship to the outer retina and retinal pigment epithelium.

METHODS

A comprehensive search of medical literature was performed through the Medline/PubMed database using search terms: choriocapillaris, choroid, quantification, biomarkers, diabetic retinopathy, age-related macular degeneration, choroidal blood flow, mean blur rate, flow deficit, optical coherence tomography, optical coherence tomography angiography, fluorescein angiography, indocyanine green angiography, OCTA, Doppler imaging, uveitis, choroiditis, white dot syndrome, tubercular serpiginous-like choroiditis, choroidal granuloma, pachychoroid, toxoplasmosis, central serous chorioretinopathy, multifocal choroiditis, choroidal neovascularization, choroidal thickness, choroidal vascularity index, choroidal vascular density, and choroidal blood supply. The search terms were used either independently or combined with choriocapillaris/choroid.

RESULTS

The imaging techniques which are used to qualitatively and quantitatively analyze choriocapillaris are described. The pathological alterations in the choriocapillaris in an array of conditions such as diabetes mellitus, age-related macular degeneration, pachychoroid spectrum of diseases, and inflammatory disorders have been comprehensively reviewed. The future directions in the study of choriocapillaris have also been discussed.

CONCLUSION

The development of imaging tools such as OCT and OCTA has dramatically improved the assessment of choriocapillaris in health and disease. The choriocapillaris can be delineated from the stromal choroid using the OCT and quantified by manual or automated methods. However, these techniques have inherent limitations due to the lack of an anatomical distinction between the choriocapillaris and the stromal choroid, which can be overcome with the use of predefined segmentation slabs on OCT and OCTA. These segmentation slabs help in standardizing the choriocapillaris imaging and obtain repeatable measurements in various conditions such as diabetic retinopathy, age-related macular degeneration, pachychoroid spectrum, and ocular inflammations. Additionally, Doppler imaging has also been effectively used to evaluate the choroidal blood flow and quantifying the choriocapillaris and establishing its role in the pathogenesis of various retinochoroidal diseases. As tremendous technological advancements such as wide-field and ultra-wide field imaging take place, there will be a significant improvement in the ease and accuracy of quantifying the choriocapillaris.

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.

Patients with central serous chorioretinopathy not only have pachychoroidal disorders but also altered retinal metabolic function

PURPOSE

The aim of our study was to compare metabolic (oxygen saturation; %) and anatomical (diameter; μm) retinal vessel parameters of patients with central serous chorioretinopathy (CSC) to those of controls.

METHODS

In this prospective cross-sectional cohort study, 72 eyes of patients with CSC were compared with 21 eyes of healthy controls. Of the 72 patients, 52 had chronic, nonactive CSC (subgroup nCSC) and 20 had active CSC (subgroup aCSC), according to activity on fluorescein angiography. Retinal vessel oximetry (RO) was performed using the Oxymap T1 oximeter. Oxygen saturation in all major peripapillary retinal arterioles (A-SO₂ ) and venules (V-SO₂ ) was measured, and their difference (A-V SO₂ ) was calculated. In addition, we evaluated the corresponding diameter in retinal arterioles (D-A) and venules (D-V). For statistical evaluation, ANOVA-based linear mixed-effects models were calculated (SPSS®; p < 0.05).

RESULTS

Central serous chorioretinopathy (CSC) patients had significantly higher A-SO₂ and V-SO₂ compared to that of controls (p = 0.031 and p = 0.018 respectively). Especially, the subgroup of aCSC patients showed significantly higher A-SO₂ and V-SO₂ values (p = 0.027 and p = 0.034, respectively). In addition, superotemporal and superonasal quadrant location showed significant interactions with A-SO₂ and V-SO₂ (p ≤ 0.03). Diameter in retinal arterioles (D-A), an venules (D-V) and A-V SO₂ findings showed no significant differences (p > 0.096).

CONCLUSION

These data indicate that patients with CSC have altered metabolic function. The presence of disease activity showed the greatest influence on RO measurement, both compared to controls and to those with inactive chronic CSC disease.

Evaluation of the choriocapillaris after photodynamic therapy for chronic central serous chorioretinopathy. A review of optical coherence tomography angiography (OCT-A) studies

PURPOSE

Emerging evidence suggests that choroidal microcirculation and microstructural changes after verteporfin photodynamic therapy (vPDT) for chronic central serous chorioretinopathy (CSC) can be shown in detail using OCT-Angiography (OCT-A). The use of OCT-A for the examination of choriocapillaris (CC) has attracted significant attention as the technique offers potential explanations for the effects of vPDT on choroidal tissue.

METHODS

A meticulous literature search was performed in the PubMed database without restriction on year of publication until June 2021. The reference list of all electronically retrieved articles was carefully reviewed for potentially relevant articles that had not been identified.

RESULTS

We identified and reviewed 11 studies reporting a comprehensive update on microvasculature and morphologic changes of the CC layer as seen on OCT-A in chronic CSC. The reviewed articles extensively analyze both the qualitative and quantitative characteristics of the CC flow pattern after applying vPDT safety-enhanced protocols. The changes in the CC plexus indicate the potential of beneficial or deleterious treatment effect on choroidal tissue remodeling. The reviewed series have revealed variability of flow pattern, vessel density, and perfusion of the CC over time.

CONCLUSION

The CC plexus alterations during the post-vPDT period in chronic CSC may imply the treatment effect on choroidal tissue, indicating the potential of anatomical or functional recovery over time. The reviewed literature may confirm the diagnostic value of OCT-A in the assessment of the pathophysiology of eyes with CSC.

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.

Effect of eplerenone on choroidal blood flow changes during isometric exercise in patients with chronic central serous chorioretinopathy

PURPOSE

To investigate choroidal blood flow changes after isometric exercise in patients with chronic central serous chorioretinopathy nontreated or treated with mineralocorticoid receptor antagonists (MRA).

METHODS

Foveolar choroidal laser Doppler flowmetry parameters - velocity (ChVel), volume (ChVol) and blood flow (ChBF) - of 22 eyes of 22 treated patients, 16 eyes of 16 untreated patients and 19 healthy controls were measured during a squatting test. Treatment consisted in MRA administration (eplerenone 50 mg/day or spironolactone 50 mg/day). The experiment comprised three successive periods: 30 seconds of rest, 2 min of continuous squatting exercise, and 150 seconds of recovery. Significance levels were calculated using a generalized estimating equation.

RESULTS

During the squatting period, nontreated CSCR eyes had a similar change in ChVel (p = 0.8), ChVol (p = 0.8), ChBF (p = 0.5) and resistance to healthy eyes. Treated CSCR eyes exhibited significantly smaller changes in ChVel (-0.1 ± 11%, p = 0.04) than healthy eyes (6 ± 8%). No significant difference was found for ChVol and ChBF between the groups. The increase in ChVol from baseline in the nontreated CSCR group (4.4 ± 9%) was lower than that of treated group (6.7%±11%; p = 0.01). Finally, ChBF and ChVel changes in the CSCR groups were not significantly different.

CONCLUSIONS

No abnormalities were detected in the changes in ChBF parameters during increased ocular perfusion pressure in nontreated CSCR patients compared with controls. MRA treatment in CSCR patients induced a significant reduction in ChBVel and an increase in ChBVol in response to isometric exercise, suggesting that MRA exerts effects on choroidal vascular changes.

Pachychoroid disease spectrum: review article

PURPOSE

The aim of this article is to do a comprehensive literature review about the current understandings of the pachychoroid disease spectrum, describing its multimodal imaging analysis, pathophysiology, differential diagnosis, and current types of management.

METHODS

This comprehensive literature review was performed based on a search on the PubMed database, of relevant pachychoroid published papers according to our current knowledge.

DISCUSSION

The pachychoroid disease spectrum, according to some authors, includes the following: pachychoroid pigment epitheliopathy (PPE), central serous chorioretinopathy (CSC), pachychoroid neovasculopathy (PNV), polypoidal choroidal vasculopathy (PCV)/aneurysmal type 1 neovascularization (AT1), and more recently focal choroidal excavation (FCE) and peripapillary pachychoroid syndrome (PPS). Each one of these entities will be described and discussed in this article.

CONCLUSION

Significant advances in multimodal imaging have enabled a better understanding of the typical choroidal changes in pachychoroid disease spectrum. The clinical knowledge and managing options about this disease significantly increased in the last years. However, it is still unclear why some eyes with typical pachychoroid disease phenotype show no evidence of RPE damage and subretinal fluid (uncomplicated pachychoroid) while others present progressive tissue damage, neovascularization, and atrophy.

Optical coherence tomography angiography of central serous chorioretinopathy: quantitative evaluation of the vascular pattern and capillary flow density

Background

This study aimed to evaluate the vascular pattern and capillary flow density (CFD) map on optical coherence tomography angiography (OCTA) images of patients affected by central serous chorioretinopathy (CSC).

Methods

In this retrospective cohort study, OCTA (AngioVue RTVue XR Avanti, Optovue) 3 × 3 mm macula scans of both eyes of patients with CSC were taken at baseline; the images were segmented and compared with OCTA scans of fellow eyes without CSC as well as age-matched healthy subjects. OCTA images were processed by quantitative textural analysis (ImageJ software) to provide an objective grading of choroidal capillary alterations. The texture of OCTA images was examined by the autocorrelation method.

Results

In eyes with CSC (40 eyes), we found six different morphological patterns of the choriocapillaris layer vasculature (CCL), likely corresponding to different grades of OCT choroidal hyporeflectivity and OCTA reduction of the decorrelation signal. Moreover, the OCTA capillary flow density map revealed capillary depletion in the superficial capillary plexus (p value = 0.0023), in the deep vascular network (p value =  < 0.0001), and in the CCL (p value = 0.0001). Such findings were not observed in healthy subjects (13 eyes).

Conclusions

OCTA in CSC is a useful tool that allows the identification of the clinical type of CSC by means of specific CCL patterns. Moreover, CFD depletion is observed in association with the inner retinal layers, pointing to an involvement of the inner blood retinal barrier in CSC. According to our results, it is plausible that the patterns observed herein may correlate to the different clinical subtypes of the disease.

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.

Choriocapillaris: Fundamentals and advancements

The choriocapillaris is the innermost structure of the choroid that directly nourishes the retinal pigment epithelium and photoreceptors. This article provides an overview of its hemovasculogenesis development to achieve its final architecture as a lobular vasculature, and also summarizes the current histological and molecular knowledge about choriocapillaris and its dysfunction. After describing the existing state-of-the-art tools to image the choriocapillaris, we report the findings in the choriocapillaris encountered in the most frequent retinochoroidal diseases including vascular diseases, inflammatory diseases, myopia, pachychoroid disease spectrum disorders, and glaucoma. The final section focuses on the development of imaging technology to optimize visualization of the choriocapillaris as well as current treatments of retinochoroidal disorders that specifically target the choriocapillaris. We conclude the article with pertinent unanswered questions and future directions in research for the choriocapillaris.

USE OF CHOROIDAL VASCULARITY INDEX FOR CHOROIDAL STRUCTURAL EVALUATION IN CENTRAL SEROUS CHORIORETINOPATHY WITH CHOROIDAL NEOVASCULARIZATION

PURPOSE

To evaluate choroidal vascular structure in eyes with central serous chorioretinopathy (CSC) by assessing the choroidal vascular index (CVI).

METHODS

We retrospectively analyzed the medical records of 117 eyes with CSC. Subjects were divided into 4 groups according to clinical characteristics: 1) acute CSC (N = 29), 2) non-neovascularized chronic CSC without flat irregular pigment epithelial detachment (N = 49), 3) non-neovascularized chronic CSC with flat irregular pigment epithelial detachment (N = 21), and 4) chronic CSC with choroidal neovascularization (N = 18). Subfoveal choroidal area (1,500 mm) of swept source optical coherence tomography scans were divided into luminal and stromal areas by the image binarization technique. The CVI was defined as the ratio of the luminal to the total subfoveal choroidal area.

RESULTS

The CVI was significantly lower in eyes of Group 4 than those of other groups (all P < 0.05). The subfoveal choroidal thickness was significantly lower in Group 4 than in Groups 1 and 2 (P < 0.05), but regression analysis showed no association with the CVI.

CONCLUSION

Decreased CVI may reflect choroidal vascular structure changes in eyes with choroidal neovascularization complicating CSC. These findings suggest that the CVI could be useful for evaluating choroidal vascular changes in eyes with CSC.

Correlation of sectoral choroidal vascularity with angiographic leakage in central serous chorioretinopathy

PURPOSE

To correlate sectoral choroidal vascularity with angiographic leakage in eyes with central serous chorioretinopathy (CSCR).

METHODS

This was a retrospective, cross-sectional study including patients with active CSCR. Multimodal imaging including fundus fluorescein angiography (FFA) and optical coherence tomography (OCT) were performed to identify leakage site and obtain choroidal measurements, respectively. An automated algorithm was used to perform shadow compensation, choroidal boundary localization and binarization, three (3-D) dimensional mapping, and early treatment of diabetic retinopathy study (ETDRS) grid based choroidal quantification that is, choroidal thickness (CT) and choroidal vascularity index (CVI). Nested analysis of variance (ANOVA) was performed to compare CT and CVI in different sectors.

RESULTS

Thirty-two eyes with active CSCR were analyzed. CT values varied significantly among the sectors (range, 450.27-482.63 µm; p = 0.005) and rings (range, 459.71-480.45 µm; p < 0.001), however, CVI failed to show significant variation among various segments (sectors, rings, and quadrants; range, 0.53-0.54; all p values > 0.05). Among 25 leaking spots in 25 different sectors, 12 (48%) had an increased CT compared to the overall CT whereas only 24% had increased CVI compared to overall CVI. Mean CT and CVI of the sectors with leakage (427.1 ± 81.1 µm; 0.51 ± 0.05) and remaining sectors without leakage (411.3 ± 73.9 µm; 0.53 ± 0.04) were not statistically different (p = 0.48; p = 0.12, respectively).

CONCLUSION

Though CT varied in different segments and increased CT corresponded to leakage points on FFA in 48% of eyes, CVI changes were more diffusely spread and local changes in CVI were not predictive of leakage location in eyes with active CSCR.

Macular microvascular changes in resolved central serous chorioretinopaty using spectral-domain optical coherence tomography angiography

PURPOSE

The purpose of this study was to evaluate microvascular changes in the retina and choriocapillaris in central serous chorioretinopathy (CSCR) patients with resolved serous detachment using optical coherence tomography angiography (OCTA).

METHOD

49 eyes of 46 patients with CSCR were included in the study. 32 eyes of 16 age-matched controls were included in the control group. Fundus photography, fluorescein angiography, spectral-domain optical coherence tomography and OCTA were used. Choriocapillaris (CC) flow area, foveal avascular zone (FAZ), parafoveal vascular density of superficial and deep capillary plexus of the acute and chronic CSCR groups were compared with the values of the control group. Contrary to previous studies, OCTA data were obtained at a time when there was no serous detachment. This was because we aimed at minimizing erroneous measurements that might arise due to serous detachment.

RESULTS

1- The acute CSCR patients (1.705±0.292mm²) were found to have lower choriocapillaris (CC) flow area compared to the control group (2.155±0.069mm²). (P<0.001). Lower CC flow area was found in the chronic CSCR patients (1.774±0.216mm²) compared to the control group (2.155±0.069mm²) (P<0.001). 2- Chronic CSCR patients (49.27%±3.84) had a lower parafoveal density in the superficial capillary plexus compared to the control group (52.25%±2.85) (P<0.05). 3- No statistically significant difference was found between the acute CSCR group (55.07%±6.29) and chronic CSCR group (52.65%±5.18) in terms of parafoveal density in the deep capillary plexus when individually compared to the control group (53.34%±2.7). 4-A positive correlation was found between the parafoveal density in the deep capillary plexus and central foveal thickness (CFT) in the chronic CSCR group (r=0.382) (P˂0.05) 5- No statistically significant difference was found in the FAZ of the acute CSCR group (0.258±0.054mm²) and chronic CSCR group (0.342±0.124mm²) when individually compared to the control group (0.311±0.1mm²). The largest mean FAZ area was found in the chronic CSCR group.

CONCLUSION

Our study showed that the pathogenesis of CSCR is characterized by choriocapillaris and retinal microvascular changes.

Serous business: Delineating the broad spectrum of diseases with subretinal fluid in the macula

A wide range of ocular diseases can present with serous subretinal fluid in the macula and therefore clinically mimic central serous chorioretinopathy (CSC). In this manuscript, we categorise the diseases and conditions that are part of the differential diagnosis into 12 main pathogenic subgroups: neovascular diseases, vitelliform lesions, inflammatory diseases, ocular tumours, haematological malignancies, paraneoplastic syndromes, genetic diseases, ocular developmental anomalies, medication-related conditions and toxicity-related diseases, rhegmatogenous retinal detachment and tractional retinal detachment, retinal vascular diseases, and miscellaneous diseases. In addition, we describe 2 new clinical pictures associated with macular subretinal fluid accumulation, namely serous maculopathy with absence of retinal pigment epithelium (SMARPE) and serous maculopathy due to aspecific choroidopathy (SMACH). Differentiating between these various diseases and CSC can be challenging, and obtaining the correct diagnosis can have immediate therapeutic and prognostic consequences. Here, we describe the key differential diagnostic features of each disease within this clinical spectrum, including representative case examples. Moreover, we discuss the pathogenesis of each disease in order to facilitate the differentiation from typical CSC.

Choroidal and Retinal Changes After Systemic Adrenaline and Photodynamic Therapy in Non-Human Primates

Purpose

To determine the tomographic, angiographic, and histologic changes in the choroid and retina of cynomolgus monkeys after systemic adrenaline and verteporfin photodynamic therapy (vPDT).

Methods

Six cynomolgus monkeys (12 eyes) were treated with vPDT only (n = 2), adrenaline only for eight weeks (n = 2), adrenaline for eight weeks with vPDT at week 4 (n = 4), and adrenaline for 12 weeks and vPDT at week 8 (n = 4). Spectral-domain optical coherence tomography, angiography, and autofluorescence were performed at baseline and every 14 days thereafter until 28 days after adrenaline therapy or vPDT. Choroid parameters included choroidal thickness (CT) changes and structural changes using semiautomated image binarization. Histology with light and electron microscopy was performed.

Results

Adrenaline resulted in subfoveal CT increase at week 4 compared with baseline (3.4%, P = 0.010), with further increase at week 8 (3.9%, P = 0.007). This correlated with choroidal luminal area increase (16.0% at week 8 compared with baseline, P = 0.030). Outer retinal changes included subretinal fluid, ellipsoid zone (EZ) disruption, photoreceptor elongation, and sub/intraretinal bright dots. Hypocyanescent spots surrounded by leakage was observed. Histology showed dilated choroidal vessels, intracytoplasmic vacuoles, and retinal pigment epithelium (RPE) enlarged basal infoldings. The vPDT decreased subfoveal CT at four weeks after vPDT (−7.5%, P = 0.007). This correlated with choroidal stromal area decrease (−18.0%, P < 0.010). Within the treatment spot, there was outer retinal atrophy, EZ disruption, irregular RPE thickening, intense hypoautofluorescence, hyperfluorescence, and hypocyanescence. On histology, there were outer retina, RPE, and choroid changes.

Conclusions

Adrenaline induces choroidal vessel dilation and CT increase. The vPDT decreases CT because of a reduction in choroidal stromal component.

Long term outer retinal changes in central serous chorioretinopathy submitted to half-dose photodynamic therapy

PURPOSE

To evaluate long-term changes in the foveal and parafoveal outer retina after half-dose photodynamic therapy (HD-PDT) in central serous chorioretinopathy (CSC).

METHODS

Retrospective study including CSC patients submitted to HD-PDT. Best corrected visual acuity (BCVA) was evaluated. Spectral-domain optical coherence tomography automatic segmentation algorithm was used and data on retinal, inner retinal, outer retinal and outer nuclear layers (ONL) in both foveal 1 mm (C) and parafoveal 3 mm ETDRS circles for the superior, nasal, inferior and temporal sectors, were obtained at baseline and 3, 12 and 24 months post-treatment. Subfoveal choroidal thickness, photoreceptors' outer segment thickness, subretinal fluid (SRF) height and width were also measured.

RESULTS

Twenty-one eyes of 15 patients were included. At baseline, the mean ONL thickness in the foveal area was significantly thinner in affected eyes compared to their fellow unaffected ones (55,50 ± 32,75 μm vs 93,00 ± 17,0 μm; p = 0,011), and was negatively correlated to logMAR BCVA (R=-0,601, p = 0,008) ONL thickness increased by 10,94 ± 11,88 μm at 24 months in the foveal area, and all the parafoveal sectors presented a similar increase. Baseline SRF width was significantly correlated with baseline BCVA (R1 = 0,483, p = 0,036), and with ONL thickness in all sectors.

CONCLUSION

In our study we found a significant long-term increase in foveal and parafoveal ONL thickness in CSC after HD-PDT, suggesting that this seems to be a safe treatment for the outer retina. This is the first study mapping the outer retinal changes in the macular area to 24 months follow up.

One-year comparison of anti-vascular endothelial growth factor and half-dose photodynamic therapies for pachychoroid neovasculopathy

BACKGROUND

To compare 1-year outcomes between anti-vascular endothelial factor (VEGF) therapy and half-dose photodynamic therapy (PDT) for treatment-naive pachychoroid neovasculopathy (PNV) with subretinal fluid (SRF).

METHODS

Consecutive patients with treatment-naive PNV patients with SRF treated with intravitreal anti-VEGF injections or half-dose PDT followed by as-needed schedule with 1-year follow-up were studied retrospectively.

RESULTS

Eighty-two eyes of 82 patients were eligible: 50 eyes underwent anti-VEGF therapy and 32 eyes underwent half-dose PDT. SRF resolved in 41 (82%) of 50 eyes after initial three monthly injections and 31 (96.9%) of 32 eyes 3 months after initial PDT, and 43 (86%) eyes and 30 (94%) eyes 1 year after initial anti-VEGF injection and half-dose PDT, respectively. No significant differences were found in SRF resolution rates 3 months and 1 year after initial treatment between the two treatment groups. Best-corrected visual acuity (BCVA) improved significantly after initial three monthly injections (P = 0.025) and initial PDT (P = 0.022) compared with baseline; the improvements were maintained 1 year after initial treatment in the two treatment groups. No significant differences were found in BCVA between the two treatment groups at baseline and throughout the 1-year follow-up period. Mean (± standard error) numbers of intravitreal injections and PDT over 12 months were 3.7 ± 0.16 and 1.1 ± 0.06, respectively.

CONCLUSIONS

Both treatments are similarly effective on SRF resolution and VA improvement 1 year after the initial treatment. Half-dose PDT may be an option for treatment for PNV. Prospective studies are required to confirm these findings.

Early alterations in retinal microvasculature on swept-source optical coherence tomography angiography in acute central serous chorioretinopathy

The purpose of the study was to evaluate the retinal blood flow in patients with acute central serous chorioretinopathy (CSC) over an observational period of 1 month using swept-source optical coherence tomography (SS-OCTA), focusing especially on changes in the area of subretinal fluid (A-SRF). We correlated these findings with conventional indocyanine green angiography (ICGA). ICGA and SS-OCTA images were collected and analyzed of 12 eyes of 12 patients. The A-SRF was annotated and a qualitative analysis of choriocapillaris, the vessel density (VD) and perfusion density (PD) of the retinal superficial capillary plexus (SCP) and the deep capillary plexus (DCP) was performed in A-SRF and the unaffected remaining area (RA). The VD and PD in the DCP were statistically significantly lower in A-SRF than in the RA at baseline. (VD: p = 0.014; PD: p = 0.036). After 1 month, there was a statistically significant difference in the VD and PD of the DCP (VD: p = 0.015; PD: p = 0.014), and for the PD of the SCP between the A-SRF and the RA (p = 0.015), with lower values in the A-SRF. We found low perfused areas in choriocapillaris corresponding to hypofluorescent areas on ICGA. In conclusion there is a difference in VD and VD of the DCP in the area of SRF in acute CSC. These alterations may lead to a chronic change in the microvasculature and potentially to morphological changes.

THE INCIDENCE OF NEOVASCULARIZATION IN CENTRAL SEROUS CHORIORETINOPATHY BY OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

PURPOSE

To evaluate the incidence of neovascularization (NV) secondary to central serous chorioretinopathy (CSC)-a condition belonging to the spectrum of pachychoroid disorders by means of optical coherence tomography angiography.

METHODS

One hundred and seventy five eyes with CSC were evaluated in this retrospective observational study. The eyes with acute or chronic CSC with no NV were included in Group 1, and those with NV were evaluated in Group 2. Only eyes that had undergone structural optical coherence tomography and optical coherence tomography angiography were included. Age, best-corrected visual acuity, and subfoveal choroidal thickness were evaluated in all eyes. In Group 2, the type and morphology of NV and the occurrence of exudation were considered.

RESULTS

Of a total of 175 eyes with CSC, 86 had the acute form and 89 the chronic. Approximately 140 belonged to Group 1 (80%) and 35 to Group 2 (20%). Approximately 39.2% of all patient with chronic CSC developed NV. Mean age in Groups 1 and 2 was 53.3 years (±10.9) and 66.6 years (±10.2), respectively. Mean best-corrected visual acuity in Groups 1 and 2 was 45.7 (±11.7) and 30.9 (±17.9) early treatment diabetic retinopathy study letters, respectively. Mean CCT in Group 1 and 2 was 417.5 µm (±123) and 344.2 µm (±165.9), respectively. In Group 2, all patients had Type 1 NV (100%); 29 eyes (83%) had filamentous feature, and 6 eyes (17%) had irregular shape. Silent nonexudative NV was observed in 7 eyes (20%), all belonging to Group 2.

CONCLUSION

The use of optical coherence tomography angiography in everyday clinical practice allows for the accurate analysis of the chorioretinal vascular setting, with the identification of new vessels that could remain misdiagnosed.

Quantitative Assessment of Asymmetric Choroidal Outflow in Pachychoroid Eyes on Ultra-Widefield Indocyanine Green Angiography

Purpose

To quantitatively demonstrate asymmetric choroidal outflow in pachychoroid (central serous chorioretinopathy [CSC]/pachychoroid pigment epitheliopathy [PPE]) eyes using mid-phase, ultra-widefield indocyanine green angiography (UWF ICGA) images.

Methods

Eyes with a clinical diagnosis of CSC/PPE were imaged with multimodal imaging including UWF ICGA (Optos California). Quadrant brightness was measured by manually segmenting based on vortex vein location, calculating the brightness “max-min” value to assess nonuniformity between quadrants, and comparing between CSC/PPE and control eyes. A multivariate linear regression was performed to determine, across individual eyes, which specific quadrants have the greatest brightness in pachychoroid eyes, after taking into account patient-eye-specific variability.

Results

Thirty-three eyes (18 patients) with CSC/PPE along with 16 eyes of 9 controls had a mean age of 51.94 ± 9.72 vs. 53.78 ± 17.92 years (P = 0.731), respectively. Max-min analysis showed significantly increased likelihood of nonuniform drainage between vortex veins in both CSC/PPE and control eyes. Multivariate linear regression in control eyes showed that on average, the inferotemporal quadrant was significantly brighter than the superonasal quadrant (9.72 units, P < 0.001). Among CSC/PPE eyes, adjusting for the preferential, nonuniform drainage in control eyes, the inferonasal and inferotemporal quadrants in CSC/PPE eyes remained significantly brighter than the reference quadrant by 5.36 units (P = 0.034) and 7.51 units (P = 0.008), respectively.

Conclusions

Asymmetric choroidal venous outflow occurs in both control and CSC/PPE eyes based on UWF ICGA quantitative brightness levels in each quadrant. Increased brightness levels along inferior quadrants in mid-phase ICGA images suggest venous outflow congestion among eyes with CSC or PPE.

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY-GUIDED PHOTODYNAMIC THERAPY FOR ACUTE CENTRAL SEROUS CHORIORETINOPATHY

PURPOSE

To compare the anatomic results of optical coherence tomography angiography (OCTA)-guided half-dose photodynamic therapy (PDT) versus indocyanine green angiography (ICGA)-guided PDT in eyes with acute central serous chorioretinopathy.

METHODS

This study is a prospective, single-center, noninferiority, double-masked, randomized, controlled clinical trial. Fifty-one eyes of 45 patients with acute central serous chorioretinopathy were recruited, and randomized to an ICGA-guided group and an OCTA-guided group. The primary outcome measures were the rates of complete subretinal fluid (SRF) resolution at 1 month and 3 months.

RESULTS

Forty-six eyes of 40 patients finished the follow-up and were analyzed. In the OCTA-guided group, the SRF was completely resolved in 13 (56.5%) eyes within 1 month and in 21 (91.3%) eyes within 3 months. In the ICGA-guided group, the SRF was resolved in 16 (69.6%) of the eyes within 1 month and in 22 (95.7%) of the eyes by 3 months. Optical coherence tomography angiography-guided PDT was demonstrated noninferior to ICGA-guided PDT for SRF resolution rate at 3 months (P = 0.016), but not at 1 month (P = 0.311) for acute central serous chorioretinopathy patients. Subretinal fluid did not recur in any of the eyes in the OCTA-guided group, but did recur in 2 eyes (8.7%) of the ICGA-guided group during the 3-month follow-up period.

CONCLUSION

Optical coherence tomography angiography-guided PDT seemed to be noninferior to ICGA-guided PDT for resolution of SRF at 3 months in eyes with acute central serous chorioretinopathy.

Optical coherence tomography angiography of central serous chorioretinopathy patients' response to breath-holding manoeuvre

PURPOSE

To demonstrate through the use of optical coherence tomography angiography (OCTA) that normal vasoreactivity cannot be monitored in central serous chorioretinopathy (CSR) patients in the presence of vasoactive stimuli owing to hypoxia caused by the breath-holding manoeuvre (BHM).

METHODS

This cross-sectional study included a total of 210 eyes, including 70 CSR patients (70 symptomatic eyes, 70 asymptomatic eyes) and 70 control group. Images of the macula (3 × 3 mm) and the optic disc (4.5 × 4.5 mm) were obtained at the baseline and after BHM using OCTA. The change in vascular parameters in the OCTA after BHM was evaluated in CSR patients and the control group.

RESULTS

In the symptomatic eyes of CSR patients, the mean whole image vessel density (VD) in the superficial capillary plexus decreased from 48.0 ± 3.5% under baseline conditions to 46.0 ± 4.5% after BHM (p < 0.01), and the mean whole VD in the deep capillary plexus decreased from 47.9 ± 8.0% under baseline conditions to 46.9 ± 6.7% after BHM (p < 0.01). The OCTA after BHM revealed a decrease in the mean whole image VD of the optic disc in both symptomatic (50.4 ± 2.1% to 49.6 ± 2.0%, p < 0.05) and asymptomatic (50.9 ± 1.8% to 50.4 ± 1.9%, p < 0.05) eyes of CSR patients. No difference for any mean VD of the control group was seen between the baseline and after BHM. Outer retinal flow areas increased significantly after BHM compared with the baseline in both eyes of CSR patients.

CONCLUSION

These results suggest that CSR pathogenesis is related to an imbalance in local vascular regulation and the sympathetic activity of the autonomic nervous system. This technique constitutes a new way of studying retinal vascular changes and may be applied to CSR patients.

Central serous chorioretinopathy: An update on risk factors, pathophysiology and imaging modalities

Central serous chorioretinopathy (CSC) is a common form of vision loss, typically seen in working-age men. The pathophysiology behind CSC still eludes us, however significant advances have been made in understanding this disease over the last decade using information from genetic and cell-based studies and imaging modalities. This review aims to give an overview of the current pathophysiology hypotheses surrounding CSC in addition to future directions in cellular work from human induced pluripotent stem cell derived choroidal endothelial cells from CSC patients. Furthermore, this review will provide the reader with an update on the clinical aspects of CSC including risk factors, diagnostic challenges and findings from multimodal imaging.

Pachychoroid: current concepts on clinical features and pathogenesis

PURPOSE

The term "pachychoroid" refers to a newly described phenotype in which functional and structural choroidal changes are thought to play a key pathogenic role in a spectrum of related retinal disorders. A more detailed understanding of how the choroid is involved within this spectrum and a better knowledge of the most relevant clinical signs of the pachychoroid phenotype are important to differentiate these disorders from other retinal conditions. Our objectives are to provide a literature review of pachychoroid and the commonalities that may be present across pathologies included in the spectrum, and to provide details on the examination, monitoring, and management of these disorders.

METHODS

We searched the PubMed web platform to identify relevant studies using the following keywords: pachychoroid, pachychoroid pigment epitheliopathy, pachychoroid neovasculopathy, aneurysmal type 1 neovascularization, focal choroidal excavation, peripapillary pachychoroid syndrome, vasculopathy pachysclera, pachychoroid geographic atrophy, and pachydrusen. We selected 157 publications and identified the most important features related to pachychoroid.

RESULTS

The presence of hypertrophic or congested vessels in the choroid, not thickened choroid per se, under an area of reduced or absent choriocapillaris in the posterior pole seems to be the most salient feature of pachychoroid. However, other qualitative/quantitative features are needed to differentiate the uncomplicated pachychoroid from the pathological pachychoroid clinical spectrum, which may be associated with exudation, neovascularization, and/or retinal pigment epithelium and photoreceptor atrophy.

CONCLUSIONS

The most salient feature of pachychoroid appears to be the presence of large vessels under an area of reduced or absent choriocapillaris. Knowledge of the features and pathogenesis of the different disorders in the pachychoroid spectrum may assist in the management of patients.

Central serous chorioretinopathy and heart rate variability analysis with a smartphone application

The purpose of this study was to quantitatively analyze heart rate variability (HRV) in patients with central serous chorioretinopathy (CSC) by using a smartphone-based application (ANBAI: DUMSCO Inc.) for measurement, and to clarify its relationships with CSC. The subjects were 64 CSC patients (mean age 48.7 ± 7.6 years, 57 males and 7 females). After providing consent, the patients downloaded ANBAI apps to their smartphones. HRV was measured by photoelectric volume pulse wave measurement with a smartphone camera each morning for a minimum of 1 week. The primary outcome was to analyze HRV by calculating log LF/HF (Low Frequency/High Frequency components), an index of autonomic tone, which was then compared with a control group of 35,226 individuals from the application. Secondary outcome measures included disease duration, body mass index, exercise habits, smoking history, steroid use, occupation, lifestyle regularity, psychological fatigue, physical fatigue, and average sleep time. The log LF/HF was significantly higher in the patient group than in the control group (P < 0.001). Log LF/HF was significantly lower in patients with exercise habits as a factor contributing to log LF/HF in the patient group (P = 0.019). Analysis of HRV in CSC patients showed an impairment of the autonomic nervous system. Exercise habits may also be associated with CSC.

Current diagnosis and management strategies in pachychoroid spectrum of diseases (Review)

This review presents a systematic analysis of the literature regarding the pachychoroid disease spectrum nomenclature, diagnosis criteria and therapeutic options. Pachychoroid related diseases are a new concept, introduced into the ophthalmological nomenclature in 2013 and evolving both as concept and as classification since then. The six disorders included in this phenotype have some common characteristics (thick choroid, pachyvessels, attenuation of the choriocapillaris), but also show individual features. The classification of the pachychoroid spectrum was revised many times, with the recent addition of the focal choroidal excavation (FCE) and peripapillary pachychoroid syndrome (PPS). As the terminology is developing, so is the number of case reports and case series from the initial report in 2013 to 57 reports in 2019. This review takes into account both the current literature and the clinical experience of the authors, emphasizing the understanding of the pathogenesis and aiming to update the therapeutic options available.

Central Serous Chorioretinopathy: Multimodal Imaging and Management Options

Central serous chorioretinopathy (CSCR) is an idiopathic maculopathy characterized by thickened choroid, retinal pigment epithelial detachment, and variable subretinal fluid. CSCR predominantly affects young men, with risk factors including corticosteroid use, the type A behavior pattern, and psychological stress. While usually self-limited with a good visual prognosis, recurrent and persistent CSCR can lead to outer retinal and/or retinal pigment epithelial atrophy, choroidal neovascularization, and visual loss. This article reviews current multimodal imaging and treatment options, which include observation, mineralocorticoid receptor antagonists, thermal laser photocoagulation, and off-label photodynamic therapy with verteporfin.

Pachychoroid neovasculopathy: a type-1 choroidal neovascularization belonging to the pachychoroid spectrum-pathogenesis, imaging and available treatment options

PURPOSE

The purpose of this paper is to provide a meaningful literature review about the epidemiology, pathogenesis, imaging and treatment of pachychoroid neovasculopathy (PNV).

METHODS

A computerized search from inception up to December 2019 of the online electronic database PubMed was performed using the following search string: "pachychoroid neovasculopathy". The reference list in each article was scanned for additional relevant publications.

RESULTS

PNV is a type-1 choroidal neovascularization, overlying focal areas of choroidal thickening and dilated choroidal vessels. It can develop in patients affected by pachychoroid pigment epitheliopathy or chronic central serous chorioretinopathy. The absence of drusen, the presence of pachydrusen, younger age of onset and choroidal thickening distinguish it from neovascular age-related macular degeneration (AMD). PNV incidence and prevalence data are lacking. Its pathophysiology is not fully understood, but angiogenic mechanisms involved in neovascular AMD may be different from those in PNV. Due to optical coherence tomography (OCT) improvements, PNV can be diagnosed more easily than before. In particular, PNV shows a shallow pigment epithelium detachment with an undulating retinal pigment epithelium over a subfoveal choroidal thickening, associated with vein enlargement in Haller's layer (named pachyvessels) and choriocapillaris thinning. On OCT angiography, PNV reveals tangled hyper-reflective filamentous neovessels in the choriocapillaris itself. The current first-line PNV treatment is intravitreal anti-VEGF (vascular endothelial growth factor) injections with a treat-and-extend regimen. In particular, aflibercept shows a higher rate of fluid absorption than others. In the case of fluid recurrence or persistence, photodynamic therapy is a valid alternative.

CONCLUSION

Ongoing research into pathophysiology and imaging improvements may be helpful in defining prognostic criteria and stratifying patient risk, allowing responsible monitoring and management of PNV.