Pulsation of anastomotic vortex veins in pachychoroid spectrum diseases

Association between the arm-to-choroidal circulation time and clinical profile in patients with polypoidal choroidal vasculopathy

PURPOSE

To investigate the association between the arm-to-choroidal circulation time (ACT) on indocyanine green angiography (IA) and clinical profile in patients with polypoidal choroidal vasculopathy (PCV).

STUDY DESIGN

Single-center retrospective study.

METHODS

We included 38 eyes of 38 patients with PCV diagnosed using multimodal imaging and did not undergo previous treatment. All patients were treated with monthly aflibercept injections for 3 months and treat-and-extend regimens for the subsequent 12 months. Posterior vortex vein ACT was assessed on the first visit using Heidelberg IA. The patients were divided into two groups: ACT ≥20 s (L group; eight eyes) and ACT <20 s (S group; 30 eyes). The clinical profiles before and after treatment were analyzed to assess associations with ACT.

RESULTS

The mean ACT was 16.39±3.3 s (L group: 21.25±1.49 s, women:men=2:6, mean age: 77.3±6.5 years; S group: 15.10±2.17 s, women:men=7:23, mean age: 75.5±6.9 years). No significant difference was observed in the mean subfoveal choroidal thickness between the L and the S groups (176±75 μm vs. 230±79 μm, P=0.10). However, there were significant differences between the L and S groups in retinal fluid accumulation and hemorrhage recurrence (eight/eight eyes, 100% vs. 13/30 eyes, 43%, P<0.001), mean aflibercept injections (8.8±1.6 vs. 7.0±1.6, P<0.01) during the 12-month period, and the number of polypoidal lesions (1.8±0.7 vs. 1.3±0.5, P<0.05).

CONCLUSION

Patients with PCV and ACT >20 s are more likely to experience exudative change recurrence in the retina during treatment because they have more polypoidal lesions.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

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

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.

COMPLEX HEMODYNAMICS OF INTERVORTEX VEIN ANASTOMOSES IN HIGHLY MYOPIC EYES

PURPOSE

To analyze the complex pattern of filling of the intervortex vein (IVV) anastomoses through large trunks in highly myopic eyes based on indocyanine green angiographic (ICGA) videos.

METHODS

The medical records of 1,060 consecutive highly myopic eyes that had undergone ICGA were studied. IVV anastomoses were identified in the ICGA images, and the ICGA images and videos were analyzed comprehensively to characterize their hemodynamic features.

RESULTS

Seven eyes with IVV anastomoses through large trunks were analyzed. In the ICGA videos of six eyes, laminar flow was observed in the IVV anastomotic vessels. The laminar flow started in the arterial phase in two eyes, with pulsatile fashion in 1 of them. The flow began in the early arteriovenous transition phase in four eyes. The laminar flow continued for a mean of 12.17 ± 3.06 seconds, and the remaining section was gradually filled slower than the surrounding veins. The anastomotic trunk for the remaining one eye was too narrow to be analyzed. Four eyes had longitudinal ICGA records, and two had significant attenuation and narrowing of the anastomotic vessels.

CONCLUSION

The very early filling of part of the IVV anastomoses suggests that arteriovenous anastomoses are involved in the IVV of highly myopic eyes. However, this suggestion needs further study. There may be similar pathogenesis for IVV anastomoses either in thick or thin sclera.

Intervortex Venous Anastomosis in the Macula in Central Serous Chorioretinopathy Imaged by En Face Optical Coherence Tomography

PURPOSE

To assess the presence of macular intervortex venous anastomosis in central serous chorioretinopathy (CSCR) patients using en face optical coherence tomography (EF-OCT).

METHODS

A cross-sectional study where EF-OCT 6 × 6 and 12 × 12 mm macular scans of patients with unilateral chronic CSCR were evaluated for anastomosis between vortex vein systems in the central macula. The presence of prominent anastomoses was defined as a connection with a diameter ≥150 µm between the inferotemporal and superotemporal vortex vein systems which crossed the temporal raphe. Three groups were studied: CSCR eyes (with an active disease with the presence of neurosensorial detachment; n = 135), fellow unaffected eyes (n = 135), and healthy eyes as controls (n = 110). Asymmetries, abrupt termination, sausaging, bulbosities and corkscrew appearance were also assessed.

RESULTS

In 79.2% of the CSCR eyes there were prominent anastomoses in the central macula between the inferotemporal and superotemporal vortex vein systems, being more frequent than in fellow eyes and controls (51.8% and 58.2% respectively). The number of anastomotic connections was higher in the affected eye group (2.9 ± 1.8) than in the unaffected fellow eye group (2.1 ± 1.7) and the controls (1.5 ± 1.6) (p < 0.001). Asymmetry, abrupt terminations and the corkscrew appearance of the choroidal vessels were more frequent in the affected eyes, although no differences in sausaging or bulbosities were observed.

CONCLUSIONS

Intervortex venous anastomoses in the macula were common in CSCR, being more frequently observed in affected eyes than in fellow unaffected eyes and healthy controls. This anatomical variation could have important implications concerning the pathogenesis and classification of the disease.

Quadrant laser photocoagulation trial to ameliorate choroidal congestion in central serous chorioretinopathy

PURPOSE

To investigate the efficacy and safety of quadrant laser photocoagulation to ameliorate the choroidal congestion in central serous choroidopathy (CSC).

STUDY DESIGN

Historically controlled study.

METHODS

We prospectively studied 20 eyes with acute CSC in the quadrant laser group, in which laser photocoagulation was applied to the macular leakage point(s) as well as the quadrant of the fundus showing vortex vein dilatation. Central choroidal thickness (CCT), vertical diameter of dilated vortex vein, resolution rate of serous retinal detachment (SRD), and visual field were evaluated post-treatment. We also compared the results with those of 18 retrospectively analyzed eyes with acute CSC in an external control group, in which laser photocoagulation had been applied only to the macular leakage point(s).

RESULTS

In the quadrant laser group, 2 eyes were excluded from data analysis due to choroidal neovascularization (CNV). CCT was significantly reduced in both groups, but more significantly in the quadrant laser group. The vertical diameter of the dilated vortex vein was significantly decreased only in the quadrant laser group. The resolution rate of SRD was similar in the two groups. In the quadrant laser group, 8 eyes (44.4%) showed mild deterioration of the visual field, consistent with the area subjected to quadrant laser photocoagulation.

CONCLUSION

Quadrant laser photocoagulation can have limited efficacy for ameliorating vortex vein congestion in CSC. When laser photocoagulation to the macular area is combined with quadrant laser photocoagulation, attention must be paid to the possible development of CNV and visual field deterioration.

Choroidal arteriovenous anastomoses: a hypothesis for the pathogenesis of central serous chorioretinopathy and other pachychoroid disease spectrum abnormalities

The pachychoroid disease spectrum (PDS) includes several chorioretinal diseases that share specific choroidal abnormalities. Although their pathophysiological basis is poorly understood, diseases that are part of the PDS have been hypothesized to be the result of venous congestion. Within the PDS, central serous chorioretinopathy is the most common condition associated with vision loss, due to an accumulation of subretinal fluid in the macula. Central serous chorioretinopathy is characterized by distinct risk factors, most notably a high prevalence in males and exposure to corticosteroids. Interestingly, sex differences and corticosteroids are also strongly associated with specific types of arteriovenous anastomoses in the human body, including dural arteriovenous fistula and surgically created arteriovenous shunts. In this manuscript, we assess the potential of such arteriovenous anastomoses in the choroid as a causal mechanism of the PDS. We propose how this may provide a novel unifying concept on the pathophysiological basis of the PDS, and present cases in which this mechanism may play a role.

Angiopoietin-1 Is Required for Vortex Vein and Choriocapillaris Development in Mice

BACKGROUND

The choroidal vasculature, including the choriocapillaris and vortex veins, is essential for providing nutrients to the metabolically demanding photoreceptors and retinal pigment epithelium. Choroidal vascular dysfunction leads to vision loss and is associated with age-related macular degeneration and the poorly understood pachychoroid diseases including central serous chorioretinopathy and polypoidal choroidal vasculopathy that are characterized by formation of dilated pachyvessels throughout the choroid.

METHODS

Using neural crest-specific Angpt1 knockout mice, we show that Angiopoietin 1, a ligand of the endothelial receptor TEK (also known as Tie2) is essential for choriocapillaris development and vortex vein patterning.

RESULTS

Lacking choroidal ANGPT1, neural crest-specific Angpt1 knockout eyes exhibited marked choriocapillaris attenuation and 50% reduction in number of vortex veins, with only 2 vortex veins present in the majority of eyes. Shortly after birth, dilated choroidal vessels resembling human pachyvessels were observed extending from the remaining vortex veins and displacing the choriocapillaris, leading to retinal pigment epithelium dysfunction and subretinal neovascularization similar to that seen in pachychoroid disease.

CONCLUSIONS

Together, these findings identify a new role for ANGPT1 in ocular vascular development and demonstrate a clear link between vortex vein dysfunction, pachyvessel formation, and disease.

Vortex vein congestion in the monkey eye: A possible animal model of pachychoroid

Purpose

To create vortex vein congestion in the monkey eye as a possible pachychoroid model.

Methods

We ligated superotemporal and inferotemporal vortex veins at the surface of the sclera in monkey eyes. Optical coherence tomography (OCT) and indocyanine green angiography (ICGA) were performed before and 2, 7, and 28 days after the vortex vein ligations to investigate changes in vortex vein morphology and alterations in choroidal blood flow.

Results

Before the vortex vein ligations, en face OCT and ICGA images showed well organized vortex veins as well as horizontal and vertical watershed zones. Two days after the vortex vein ligations, dilatation of the superotemporal and inferotemporal vortex veins as well as intervortex venous anastomoses were seen on en face OCT and ICGA images. B-mode OCT images showed choroidal thickening associated with dilatation of the outer choroidal vessels. Moreover, video ICGA revealed choriocapillaris filling delay and pulsatile flow in the dilated vortex veins. At 7 and 28 days after we ligated the vortex veins, these findings were reduced, except for the intervortex venous anastomoses.

Conclusions

We created a monkey model of vortex vein congestion by ligating two vortex veins. This animal model demonstrated pachychoroid-related findings, indicating that vortex vein congestion is involved in the pathogenesis of pachychoroid. However, remodeling of the choroidal drainage route via intervortex venous anastomosis appeared to compensate for the vortex vein congestion created in this model.

A new insight into pachychoroid diseases: Remodeling of choroidal vasculature

Purpose

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

Methods

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

Results

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

Conclusions

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

Clinical characteristics and pachychoroid incidence in Japanese patients with neovascular age-related macular degeneration

The phenotypes of neovascular age-related macular degeneration (nAMD) are recognized as differing between Caucasian and Asian patients. Pachychoroid is thought to be more prevalent in Asians than in Caucasians, and may be involved in the development of nAMD in Asian patients. Therefore, we investigated the clinical characteristics and pachychoroid incidence in Japanese patients with nAMD. We retrospectively analyzed 385 eyes of 370 consecutive Japanese patients with treatment naïve nAMD. According to the nAMD nomenclature, type 1 macular neovascularization (MNV) was observed in 132 eyes (34.3%), polypoidal choroidal vasculopathy (PCV) in 137 (35.6%), mixed type 1 and type 2 MNV in 32 (8.3%), type 2 MNV in 43 (11.2%), and type 3 MNV in 41 (10.6%). Pachychoroid was seen in 58.3% of type 1 MNV, 75.2% of PCV, 34.4% of mixed type 1 and type 2 MNV, 14.0% of type 2 MNV, and 0% of type 3 MNV. Compared to nAMD patients without pachychoroid (188 eyes), those who had nAMD with pachychoroid (197 eyes) were significantly younger, had a higher proportion of males, greater central choroidal thickness, and a higher frequency of macular vortex vein anastomoses (all P < 0.001). Furthermore, drusen subtypes differed significantly between the two groups (P < 0.001). These results suggest that most Japanese nAMD patients might have type 1 MNV or PCV. Moreover, in approximately half of patients, nAMD might be associated with pachychoroid, and choroidal congestion may be involved in the development of MNV in these cases.