Choroidal Vascular Abnormalities by Ultra-widefield Indocyanine Green Angiography in Polypoidal Choroidal Vasculopathy

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.

Quantification of Choroidal Vascular Hyperpermeability on Ultra-Widefield Indocyanine Green Angiography in Macular Neovascularization

To obtain a quantitative parameter for the measurement of choroidal vascular hyperpermeability (CVH) on ultra-widefield indocyanine green angiography (UWICGA) using an objective analysis method in macular choroidal neovascularization (CNV). A total of 113 UWICGA images from 113 subjects were obtained, including with 25 neovascular age-related macular degeneration (nAMD), 37 with polypoidal choroidal vasculopathy (PCV) (19 with thin-choroid and 18 with thick-choroid), 33 with pachychoroid neovasculopathy (PNV), and 18 age-matched controls. CVH was quantified on a gray image by the subtraction of 2 synchronized UWICGA images of early and late phases. The measured CVH parameter was compared with human graders and among CNV subtypes and correlated with choroidal vascular density (CVD) and subfoveal choroidal thickness (SFCT). The mean CVH values were 28.58 ± 4.97, 33.36 ± 8.40, 33.61 ± 11.50, 42.19 ± 13.25, and 43.59 ± 7.86 in controls and patients with nAMD, thin-choroid PCV, thick-choroid PCV, and PNV, respectively (p < 0.001). CVH was higher in thick-choroid PCV and PNV compared to the other groups (all p ≤ 0.006). The measured CVH value positively correlated with those reported by human graders (p < 0.001), CVD, and SFCT (p = 0.001 and p < 0.001, respectively). CVH can be measured objectively using quantitative UWICGA analysis. The CVH parameter differs among macular CNV subtypes and correlates with CVD and SFCT.

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

Purpose

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

Methods

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

Results

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

Conclusions

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

Clinical implications of choroidal vascular brightness using ultra-widefield indocyanine green angiography in polypoidal choroidal vasculopathy

Polypoidal choroidal vasculopathy (PCV) is characterized by choroidal vascular abnormalities including polypoidal lesion and branching vascular networks. Not only choroidal structural changes, but also choroidal hyperpermeability and congestion are also thought to be involved in pathogenesis of PCV. We investigated choroidal vascular brightness intensity (CVB) using ultra-widefield indocyanine green angiography (UWF-ICGA) images and analyzed its association with clinical features in patients with PCV. In this study, 33 eyes with PCV and 27 eyes of age-matched controls were included. CVB was measured by extracting the enhanced pixels of choroidal vessels after the reference brightness across the images was adjusted to be uniform. Associations between choroidal vascular features and the clinical features of PCV were also determined. The mean CVB was higher in PCV than control eyes, regardless of the segmented region (all p < 0.001). CVB was also higher at the posterior pole than at the periphery, and the inferior quadrants were brighter than the superior quadrants in both the PCV and control group (all p < 0.05). In affected eyes, CVB was higher than in unaffected fellow eyes at the posterior pole, whereas there was no difference at the periphery. Posterior pole CVB correlated significantly with subfoveal choroidal thickness (r = 0.502, p = 0.005), polyp number (r = 0.366 p = 0.030), and the greatest linear dimension (r = 0.680, p = 0.040). Greatest linear dimension was positively correlated with CVB at posterior pole (p = 0.040), whereas SFCT or CVD in all regions didn't show the significant correlation. The UWF ICGA results showed an increase in CVB at the inferior quadrants and posterior pole, suggesting venous outflow congestion in PCV eyes. CVB might provide more substantial information on the phenotype than other choroidal vascular features.

Vortex vein engorgement and different shapes of venous drainage systems in polypoid choroidal vasculopathy vs. age‑related macular degeneration on indocyanine green angiography

There are differences in vortex vein engorgement and appearance in polypoid choroidal vasculopathy (PCV), age-related macular degeneration (AMD), and healthy eyes. The present study aimed to use indocyanine green angiography (ICGA) to find a simple, clinically meaningful method for evaluating the filling degree of vortex veins in various eye diseases. Participant clinical characteristics were recorded. The number of vortex veins (NVV), central vortex vein diameter (CVVD), mean root area of the vortex vein (MRAVV), mean diameter of the thickest peripheral branch (MDPTB), subfoveal choroidal thickness and percentage of vortex vein anastomosis (PVVA) were obtained by marking the vortex veins on ICGA. The proportion of subretinal haemorrhage and the numbers and types of vortex veins in each quadrant were counted separately. The CVVD and MDPTB were significantly increased in the PCV compared with those in the AMD group (P<0.05). The CVVD, MRAV, and PVVA were significantly increased in the PCV compared with those in the healthy group (P<0.05). The type IV vortex vein (complete with ampulla) proportion was the lowest while the type I (vortex vein absent) proportion was the highest in the PCV group (P<0.001). NVV in the inferior-temporal region was increased in the PCV compared with that in the AMD group (P=0.034). Subretinal haemorrhage occurred in the inferior temporal choroid in 47.62% of examined eyes in PCV group, and in the superior temporal choroid in 23.81% of the PCV group, with significant differences between the quadrants (P<0.001). Vortex vein engorgement and shape differed significantly between PCV, AMD and healthy eyes. The vortex vein branches in PCV eyes were significantly dilated in the posterior pole; moreover, the peripheral choroid and the lower proportion of type IV vortex veins may be pathognomonic for PCV.

Polypoidal Choroidal Vasculopathy: Updates on Risk Factors, Diagnosis, and Treatments

There have been recent advances in basic research and clinical studies in polypoidal choroidal vasculopathy (PCV). A recent, large-scale, population-based study found systemic factors, such as male gender and smoking, were associated with PCV, and a recent systematic review reported plasma C-reactive protein, a systemic biomarker, was associated with PCV. Growing evidence points to an association between pachydrusen, recently proposed extracellular deposits associated with the thick choroid, and the risk of development of PCV. Many recent studies on diagnosis of PCV have focused on applying criteria from noninvasive multimodal retinal imaging without requirement of indocyanine green angiography. There have been attempts to develop deep learning models, a recent subset of artificial intelligence, for detecting PCV from different types of retinal imaging modality. Some of these deep learning models were found to have high performance when they were trained and tested on color retinal images with corresponding images from optical coherence tomography. The treatment of PCV is either a combination therapy using verteporfin photodynamic therapy and anti-vascular endothelial growth factor (VEGF), or anti-VEGF monotherapy, often used with a treat-and-extend regimen. New anti-VEGF agents may provide more durable treatment with similar efficacy, compared with existing anti-VEGF agents. It is not known if they can induce greater closure of polypoidal lesions, in which case, combination therapy may still be a mainstay. Recent evidence supports long-term follow-up of patients with PCV after treatment for early detection of recurrence, particularly in patients with incomplete closure of polypoidal lesions.

Peripheral and macular polypoidal choroidal vasculopathy: A retrospective comparative case series

PURPOSE

To compare clinical and imaging features and treatment outcomes between eyes having peripheral polypoidal choroidal vasculopathy (PCV) and macular PCV.

METHODS

In this retrospective comparative case series, confirmed cases of peripheral and macular PCV cases on indocyanine green angiography (ICGA) were included. The various demographic features, imaging characteristics and clinical course between cases with peripheral and macular PCV were compared and analysed.

RESULTS

Fifteen eyes of 12 patients and 22 eyes of 20 patients were diagnosed with peripheral PCV and macular PCV respectively based on polyps seen on ICGA. Mean age at presentation in peripheral and macular PCV groups were 76.3 ± 8.78 and 69.1 ± 8.64 years respectively (p = 0.038). Mean logMAR visual acuity in the peripheral and macular PCV group was 0.423 ± 0.568 and 0.535 ± 0.513 respectively (p = 0.595). Peripheral subretinal hemorrhage was noted commonly in the peripheral PCV group (n = 10, 66%) and hard exudates were common in the macular PCV (19, 86%) group. Subfoveal choroid was significantly thinner in peripheral PCV group compared to macular PCV group (215.2 ± 39.94 vs 283.3 ± 50.08; p = 0.001). At final follow-up visit, 50% eyes (n = 11) in macular PCV group were still active and 87% (n = 13) eyes in the peripheral PCV showed an inactive disease (p = 0.035).

CONCLUSION

Peripheral and macular PCV cases are two separate clinical entities having distinct pathogenesis, clinical and imaging features and treatment outcomes. Further studies are needed for understanding the pathomechanism in these distinct disease entities.

A Comparative Study of Choroidal Vascular and Structural Characteristics of Typical Polypoidal Choroidal Vasculopathy and Polypoidal Choroidal Neovascularization: OCTA-Based Evaluation of Intervortex Venous Anastomosis

BACKGROUND

The aim of this study was to compare the choroidal characteristics of typical polypoidal choroidal vasculopathy (T-PCV) and polypoidal choroidal neovascularization (P-CNV) cases, and to investigate the presence of intervortex venous anastomoses in these PCV subtypes by using en face optical coherence tomography angiography (OCTA).

METHODS

A total of 35 eyes of 33 PCV cases were included. The PCV cases were divided into T-PCV and P-CNV groups. The choroidal vascularity index (CVI) was calculated. En face OCTA images were evaluated for the presence of intervortex venous anastomoses. The diameter of the largest anastomotic Haller vessel was measured.

RESULTS

T-PCV cases had significantly higher mean CVI values (73.9 ± 3.7 vs. 70.8 ± 4.5%) than P-CNV cases (p = 0.039). Intervortex venous anastomoses were observed in 85.7% of T-PCV eyes and in 91.7% of P-CNV eyes on en face OCTA (p = 1.000). In the cases with intervortex venous anastomosis, the mean diameter of the largest anastomotic vessel on en face OCTA was 341.2 ± 109.1 µm in the T-PCV and 280.4 ± 68.4 µm in the P-CNV group (p = 0.048).

CONCLUSIONS

The higher CVI value in T-PCV may be an important feature concerning the pathogenesis and classification of PCV. Although there was no difference between the two subtypes in terms of intervortex anastomosis, more dilated anastomotic vessels were observed in the T-PCV.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

Purpose

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

Methods

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

Results

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

Conclusions

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

Structural and vascular changes of the choroid in polypoidal choroidal vasculopathy after intravitreal anti-VEGF therapy

INTRODUCTION

To identify the changes in vessel density (VD) of choriocapillaris (CC) and in subfoveal choroidal thickness (SFCT) and to evaluate their correlation with functional response after three monthly intravitreal injections of Ranibizumab (loading phase) in patients affected by Polypoidal Choroidal Vasculopathy (PCV).

METHODS

A total of 30 eyes of 30 PCV patients and 30 eyes of 30 healthy subjects as control group were enrolled in this prospective study. The best corrected visual acuity (BCVA) was measured at baseline and after one month from third intravitreal injections in each patient. The VD of CC was evaluated in macular area by means of Optical Coherence Tomography Angiography (OCTA). Central macular thickness (CMT) and SFCT were analyzed by Enhanced Depth Imaging (EDI)-OCT.

RESULTS

The VD of CC showed statistically lower values in PCV patients at baseline respect to after loading phase (LP) and normal eyes (p<0.001). CMT and SFCT revealed a statistically significant reduction after LP (p<0.001). Multiple regression analysis revealed a significant negative correlation between the reduced SFCT, CMT at baseline and the improvement of BCVA after LP (p<0.05).

CONCLUSION

The close relationship between the thinner SFCT and better visual outcome after LP reveals the role of the EDI-OCT assessment of choroid as predictive biomarker of functional response to anti-VEGF therapy. This tool could provide a quantitative evaluation of structural features of choroid avoiding mistakes of evaluation at OCTA.

Association between Vortex Vein Engorgement and Treatment Outcomes of Intravitreal Aflibercept for Polypoidal Choroidal Vasculopathy

Purpose: To investigate the influence of the number of engorged vortex veins on treatment outcomes in eyes with treatment-naïve polypoidal choroidal vasculopathy (PCV) undergoing intravitreal aflibercept monotherapy.Methods: The medical charts of 65 patients with PCV who underwent intravitreal aflibercept injection were reviewed retrospectively. The number of quadrants of vortex vein engorgement was evaluated in the middle phase of ultra-widefield indocyanine green angiography, which was classified as extended engorgement if the dilated choroidal vessels expanded the macula. Associations between treatment outcomes with age, subfoveal choroidal thickness (SFCT), central retinal thickness, and vortex vein engorgement were investigated using univariate and multivariate analyses.Results: There were no significant differences in best-corrected visual acuity (BCVA), SFCT, and central retinal thickness at baseline and 12 months, according to the number of vortex vein engorgement. However, an increase in the number of vortex vein engorgement extending to the macula was associated with a thick SFCT (p = 0.038), a greater number of injections (p = 0.041), low BCVA at 12 months (p = 0.038), and a less dry macula at 12 months (p = 0.026). In the multivariate analysis, the number of quadrants with vortex vein engorgement extending to the macula was significantly associated with BCVA changes at 12 months, total number of injections, and a dry macula at 12 months (p = 0.030, p = 0.030, p = 0.020, respectively).Conclusions: More quadrants with vortex vein engorgement extending to the macula in PCV was associated with unfavorable visual outcomes, a less dry macula at 12 months, and a greater number of injections at 1 year after intravitreal aflibercept injection. Clinicians should keep in mind that vortex vein engorgement extending to the macula may be a new biomarker in predicting treatment outcomes in PCV.

Vortex Vein Imaging: What Can It Tell Us?

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