Haller's vessels patterns in non-neovascular age-related macular degeneration

RETICULAR PSEUDODRUSEN DISAPPEARANCE AFTER DEVELOPMENT OF MACULAR NEOVASCULARIZATION

PURPOSE

To explore changes in reticular pseudodrusen (RPD) number and location after the development of macular neovascularization (MNV) in eyes with prior intermediate age-related macular degeneration, focusing on different retinal regions differently affected by MNV.

METHODS

This retrospective longitudinal study included intermediate age-related macular degeneration eyes with RPD that developed MNV. Reticular pseudodrusen were assessed at baseline when MNV was diagnosed (MNV stage) and after anti-vascular endothelial growth factor treatment. Three regions of interest were considered: MNV area, subretinal fluid (SRF) area, and a marginal area of 1,000 µm around SRF (marginal zone). Reticular pseudodrusen counts were compared with age- and sex-matched control eyes with RPD that did not develop MNV.

RESULTS

Reticular pseudodrusen number exhibited a significant decrease after MNV development in the MNV area (P = 0.048) and in the area with SRF (P = 0.078). A statistically significant decrease was also disclosed in the marginal area around SRF (P = 0.002), associated with larger SRF areas. Control eyes did not show any significant change in the RPD count.

CONCLUSION

Reticular pseudodrusen reduction after MNV development suggests a complex interplay involving the MNV itself, the presence of SRF, and trophic changes. The results of this study highlight the role of MNV in retinal nutritional balance and provide intriguing results in the RPD life cycle.

LeptoVitelliform Maculopathy: delineating a distinct clinical entity from acquired vitelliform lesions

OBJECTIVES

To characterize acquired vitelliform lesions associated with leptochoroid (i.e., diffuse choroidal thinning) and reticular pseudodrusen (RPD) and compare this phenotype to the acquired vitelliform lesion (AVL) in the dystrophic spectrum.

METHODS

This retrospective, observational case-control study enrolled 56 patients (56 eyes) affected by vitelliform lesions (AVL), including 27 patients with AVL associated with RPD and leptochoroid (i.e., choroidal thinning) referred to as LeptoVitelliform Maculopathy (LVM), and 29 AVL patients without other funduscopic abnormalities. The main structural features analysed were the integrity of the external limiting membrane (ELM), ellipsoid zone (EZ), and retinal pigment epithelium (RPE), the presence of hyporeflective spaces, and hypertransmission. Choroidal vascular index (CVI) was calculated using ImageJ software.

RESULTS

Patients with LVM were 6.69 years older and presented smaller vitelliform lesions considering both vertical (P < 0.001) and horizontal diameters (P < 0.001) with a similar visual impairment compared to the AVL group (P = 0.27). The LVM subgroup showed a greater alteration of the ELM (p < 0.001) and choroidal hypertransmission (i = 0.007), accompanied by less frequent RPE bumps (P = 0.001) and hyporeflective spaces within the vitelliform material (P = 0.002). Furthermore, the LVM group presented a lower CVI with a significant attenuation on both the luminal and stromal compartments compared to AVL (P < 0.001, both).

CONCLUSIONS

The phenotypic combination of subretinal vitelliform lesion and RPD may delineate a distinct phenotype that shares with AVL only the presence of vitelliform material and a similar visual deterioration. The presented findings of LVM highlight significant structural and microvascular alterations that may hold prognostic relevance, warranting future longitudinal studies.

Pachy-Reticular Pseudodrusen

PURPOSE

To characterize the features of a peculiar association between reticular pseudodrusen (RPD) and pachychoroid (pachy-RPD) and to compare them with eyes affected by RPD and normal/leptochoroid.

DESIGN

Observational, retrospective, case-control study.

PARTICIPANTS

Among a cohort of patients with intermediate age-related macular degeneration (AMD), we selected eyes with RPD and pachychoroid (i.e., choroidal thickness of >50 μm). A control group of RPD eyes but without pachychoroid (i.e., a choroidal thickness of <250 μm) was included.

METHODS

Number and stages of RPD were evaluated in each ETDRS subfield. Furthermore, choroidal perfusion was investigated using the choroidal vascularity index (CVI), and choriocapillaris perfusion density (PD) on structural OCT and OCT angiography.

MAIN OUTCOME MEASURES

Description of the multimodal imaging features of pachy-RPD and differences with RPD associated with normal/leptochoroid.

RESULTS

Among 111 RPD eyes, 37 were included in the pachy-RPD group and 74 in the control group. Patients with pachy-RPD were significantly younger than patients with RPD and normal/leptochoroid (mean age, 75 ± 16 and 82 ± 7 years, respectively; P = 0.002). Total RPD number was comparable between the 2 groups (P = 0.220). However, pachy-RPD eyes showed a significantly higher number of stage 1 RPD in comparison to the controls (P < 0.001), and a lower number of stage 3 (P < 0.001) and stage 4 RPD (P = 0.052). The CVI and choriocapillaris PD were greater in pachy-RPD than in the control group (P < 0.001 and P= 0.010, respectively).

CONCLUSIONS

Pachy-RPD are characterized by a different distribution of RPD stages (i.e., more early stages and fewer advanced stages) in comparison to RPD with normal/leptochoroid. Furthermore, pachy-RPD eyes showed greater perfusion indices of the choroid. These features suggest that the presence of pachychoroid could be a protective factor in the RPD evolution to the advanced AMD forms.

FINANCIAL DISCLOSURE(S)

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

Choroidal vascularity index in leptochoroid: A comparative analysis between reticular pseudodrusen and high myopia

PURPOSE

To investigate the choroidal vascularity index (CVI) in patients affected by leptochoroid.

METHODS

Three distinct age-matched cohorts were collected: patients with reticular pseudodrusen (RPD) secondary to age-related macular degeneration, patients with high-myopia, and healthy controls. CVI was calculated in the subfoveal 6000 μm diameter area.

RESULTS

54 eyes (54 patients) were included (18 eyes in each cohort). No statistical differences were disclosed in terms of age between controls, RPD patients (p = 0.062), and myopic patients (p = 0.070). Total choroidal area showed a different distribution among the 3 cohorts (p < 0.001), due to the reduction of luminal and stromal choroidal area in both RPD and myopic groups in comparison to controls (p < 0.001). Interestingly, CVI showed a different distribution between the 3 cohorts (p < 0.001). In detail, RPD group showed no changes in CVI in comparison to controls (p = 1.000), whereas the myopic group showed a higher CVI in comparison to both RPD group and controls (p < 0.001 in both analyses).

CONCLUSIONS

Different changes of the choroidal vascular and stromal components characterize the leptochoroid secondary to RPD eyes and high-myopic eyes. The relative greater impairment of the vascular area in RPD eyes in comparison to myopic eyes could be at the basis of the lower development of RPD in patients with high myopia.

Towards a better understanding of non-exudative choroidal and macular neovascularization

Non-exudative macular and choroidal neovascularization (MNV and CNV) usually refers to the entity of treatment-naïve type 1 neovascularization in the absence of associated signs of exudation. Histopathological studies, dating back in the early 70s, identified the presence of non-exudative MNV, but the first clinical report of this finding was in the late 90s using indocyanine green angiography in eyes with age-related macular degeneration (AMD). With more advanced retinal imaging, there has been an ever increasing appreciation of non-exudative MNV associated with AMD and CNV with other macular disorders. However, consensus regarding the exact definition and the clinical management of this entity is lacking. Furthermore, there may be variation in the imaging features and clinical course suggesting that a spectrum of disease may exist. Herein, we review the large body of published work that has provided a better understanding of non-exudative MNV and CNV in the last decade. The prevalence, multimodal imaging features, clinical course, and response to treatment are discussed to elucidate further key insights about this entity. Based on these observations, this review also proposes a new theory about the origin and course of different sub-types of non-exudative MNV/CNV which can have different etiologies and pathways according to the clinical context of disease.

CHOROIDAL VASCULARITY INDEX IS ASSOCIATED WITH GEOGRAPHIC ATROPHY PROGRESSION

PURPOSE

To investigate the correlation between choroidal vascularity index and the enlargement of geographic atrophy (GA) lesion secondary to age-related macular degeneration during the 2-year follow-up.

METHODS

In this longitudinal observational study, 26 eyes (26 patients, mean age 75.7 ± 8.8 years) affected by GA were included. Choroidal vascularity index was calculated in the subfoveal 3000-µm area. The main outcome measure included correlation analysis between baseline choroidal vascularity index and the rate of GA enlargement.

RESULTS

During the 2-year follow-up, the mean GA area increased from 6.99 ± 5.28 mm2 to 10.69 ± 6.61 mm2(P < 0.001), accounting for a growth rate of 0.35 ± 0.20 and 0.31 ± 0.17 mm/year after the square root transformation in the first and second year of follow-up, respectively. Stromal choroidal area significantly decreased during the 2-year follow-up (P = 0.002). Interestingly, there was a significant correlation between the baseline choroidal vascularity index and the rate of GA enlargement (r=-0.432, P = 0.027) and between stromal choroidal area and the rate of GA enlargement (r = 0.422, P = 0.032). No other significant relationship was disclosed among choroidal parameters with the rate of GA enlargement.

CONCLUSION

Choroidal vascularity index impairment is strictly related to the rate of GA enlargement during the 1-year and 2-year follow-up in patients affected by GA. For this reason, choroidal vascularity index could be considered a predictor of GA progression in the clinical setting, and it could be considered as a new potential biomarker in the efficacy evaluation of new GA interventions.

Choroidal Vascularity Index in Different Cohorts of Dry Age-Related Macular Degeneration

Purpose

The purpose of this study was to investigate the choroidal luminal and interstitial stromal alterations using choroidal vascularity index (CVI) among different cohorts of dry age-related macular degeneration (dAMD) compared to healthy subjects.

Methods

Four distinct cohorts were collected: three different cohorts of patients with dAMD (i.e. drusen, reticular pseudodrusen [RPD], and geographic atrophy [GA]) and an age-matched cohort of healthy subjects (controls). CVI (the ratio between the luminal choroidal area [LCA] and the total choroidal area [TCA]) was calculated in the subfoveal 1000 µm area.

Results

One hundred twenty eyes (from 120 patients) were included (30 eyes in each cohort). The mean age was 76.6 ± 7.1 years. No statistical differences were disclosed in terms of age, axial length, and central macular thickness among study groups. TCA showed a different distribution among the four cohorts (P = 0.003), mainly due to the LCA changes (P = 0.001). Interestingly, CVI showed a different distribution among the four cohorts (P < 0.001). RPD showed a lower CVI in comparison to controls (P = 0.040), whereas GA showed a lower CVI in comparison to drusen, RPD, and controls (P = 0.001, P = 0.046, and P < 0.001, respectively).

Conclusions

Different cohorts of dAMD are characterized by different impairments of the choroidal vascular and stromal components, reflecting different degrees of AMD severity.

Translational Relevance

CVI provides insights for better understanding the pathogenesis of AMD.