Role of the choroidal vascularity index in branch retinal vein occlusion (BRVO) with macular edema

Investigation of choroidal structure changes after intravitreal anti-VEGF therapy for retinal vein occlusion

BACKGROUND

We aimed to investigate the effect of retinal vein occlusion (RVO) on the posterior segment structures of the eye and its changes with intravitreal anti-Vascular Endothelial Growth Factor (VEGF) treatment.

METHODS

This prospective longitudinal study included 29 eyes of 29 patients with RVO (17 males and 12 females) followed for 6 months. The best corrected visual acuity (BCVA), macula, choroid ticknesses and choroidal vascularity index (CVI) obtained by spectral-domain optical coherence tomography were recorded at baseline and the first, third, and sixth months after the first injection. Results were compared with fellow eyes (non-affected eyes) and age- and sex-matched controls.

RESULTS

BCVA increased significantly in the 6th month, more in the first month of injection (p < 0.05 for each). Central macular tickness, subfoveal choroid tickness, stromal and total area of choroid decreased significantly after injection (p < 0.05 for each). CVI values increased significantly, especially in the 1st month after injection (p < 0.05 for each). In eyes with Branch RVO, there was a significant decrease in the macular thickness of the occlusive areas with treatment, while there was no statistically significant change in the non-occlusive macular thickness.

CONCLUSION

Observation of changes in choroidal structure may be useful to assess the activity of RVO and predict the efficacy of anti-VEGF therapy.

THE DIAGNOSTIC VALUE OF MULTISPECTRAL FUNDUS IMAGING IN HYPERTENSIVE RETINOPATHY

PURPOSE

To observe the diagnostic value of multispectral fundus imaging (MSI) in hypertensive retinopathy (HR).

METHODS

A total of 100 patients with HR were enrolled in this cross-sectional study, and all participants received fundus photography and MSI. Participants with severe HR received fundus fluorescein angiography (FFA). The diagnostic consistency between fundus photography and MSI in the diagnosis of HR was calculated. The sensitivity of MSI in the diagnosis of severe HR was calculated by comparison with FFA. Choroidal vascular index was calculated in patients with HR using MSI at 780 nm.

RESULTS

MSI and fundus photography were highly concordant in the diagnosis of HR with a Kappa value = 0.883. MSI had a sensitivity of 96% in diagnosing retinal hemorrhage, a sensitivity of 89.47% in diagnosing retinal exudation, a sensitivity of 100% in diagnosing vascular compression indentation, and a sensitivity of 96.15% in diagnosing retinal arteriosclerosis. The choroidal vascular index of the patients in the HR group was significantly lower than that of the control group, whereas there was no significant difference between the affected and fellow eyes.

CONCLUSION

As a noninvasive modality of observation, MSI may be a new tool for the diagnosis and assessment of HR.

Central and Peripheral Changes in Retinal Vein Occlusion and Fellow Eyes in Ultra-Widefield Optical Coherence Tomography Angiography

Purpose

To explore the central and peripheral retinal and choroidal changes in retinal vein occlusion (RVO) and fellow eyes using ultra-widefield swept-source optical coherence tomography angiography (UWF-SS-OCTA).

Methods

Fifteen ischemic central RVO (CRVO), 15 branch RVO (BRVO), and 15 age-matched healthy controls were prospectively recruited. Retinal and choroidal parameters, including retinal vessel flow density (VFD) and vessel linear density (VLD), choroidal vascularity volume (CVV), choroidal vascularity index (CVI), and VFD in the large and medium choroidal vessels (LMCV-VFD), were measured in the central and peripheral regions of the 24 × 20-mm UWF-SS-OCTA images.

Results

Ischemic CRVO and BRVO eyes showed increased foveal avascular zone area, perimeter, and acircularity index (AI) compared to their fellow eyes and healthy control eyes, and RVO fellow eyes also had larger AI values than controls (P < 0.05). For ischemic CRVO and BRVO eyes versus control eyes, VFD, VLD, CVV, CVI, and LMCV-VFD decreased, but retinal thickness and volume in the superficial capillary plexus, deep capillary plexus, and whole retina increased (P < 0.05). Moreover, RVO fellow eyes also showed significantly decreased retinal VFD, LMCV-VFD, and CVI, as well as increased retinal thickness and volume, compared with control eyes (P < 0.05). Alterations were not consistent throughout the retina, as they involved only the peripheral or central regions in some cases.

Conclusions

The affected and unaffected fellow eyes of RVO patients both demonstrated central and/or peripheral structural and vascular alterations in the retina and choroid. Because UWF-SS-OCTA enables visualization and evaluation of the vasculature outside the posterior pole, it presents a promising approach to more fully characterize vascular alterations in RVO.

Longitudinal Assessment of the Choroidal Vascularity Index in Eyes with Branch Retinal Vein Occlusion-Associated Cystoid Macular Edema

INTRODUCTION

Cystoid macular edema (CME) is the most common cause of central vision loss in eyes with branch retinal vein occlusion (BRVO eyes). In recent literature, choroidal vascularity index (CVI) has been proposed to be an enhanced depth imaging optical coherence tomography (EDI-OCT) metric that may help characterize choroidal vascular changes in the setting of retinal ischemia, and potentially prognose visual outcomes and treatment patterns for patients with BRVO-related CME. This study sought to further characterize choroidal vascular changes in BRVO by comparing the CVI, subfoveal choroidal thickness (SFCT), and central subfield thickness (CST) in BRVO eyes with CME compared to unaffected fellow eyes.

METHODS

This was a retrospective cohort study. Subjects included treatment-naïve BRVO eyes with CME diagnosed within 3 months of onset of symptoms and unaffected fellow eyes. EDI-OCT images were collected at baseline and at the 12-month follow-up visit. CVI, SFCT, and CST were measured. Demographics, treatment patterns, and best-corrected visual acuity (VA) were abstracted. Median CVI, SFCT, CST, and VA were compared between the two cohorts. Longitudinal relationships between these variables were analyzed.

RESULTS

A total of 52 treatment-naïve eyes with BRVO and CME and 48 unaffected fellow eyes were identified. Baseline CVI was lower in eyes with BRVO than in fellow eyes (64.7% vs. 66.4%, P = 0.003). At 12 months, there was no difference in CVI between BRVO eyes and fellow eyes (65.7% vs 65.8%, P = 0.536). In BRVO eyes, there was a strong correlation between reduced CST and improved VA over the 12-month study period (r = 0.671, P < 0.001).

CONCLUSION

There are differences in CVI in treatment-naïve BRVO eyes with CME at presentation compared to fellow eyes, but these differences resolve over time. Anatomic changes in macular thickness in BRVO eyes with CME may be correlated with VA outcomes.

Serial choriocapillaris flow changes in eyes with branched retinal vascular obstruction (BRVO)

PURPOSE

To evaluate the choriocapillaris (CC) flow changes in branched retinal vascular obstruction (BRVO) on optical coherence tomography angiography (OCTA).

METHODS

Retrospective analysis of 29 patients with unilateral BRVO (58 eyes, including unaffected fellow eyes for controls). 4.5 x 4.5 mm macular scans were divided into 4 quadrants. Serial analyses were conducted on CC flow voids of the opposite quadrant to the active occluded area in BRVO eyes. Each of the quadrants were also compared to the occluded quadrant of resolved eyes and the contralateral quadrant of fellow eyes by matched data analysis. A regression analysis was performed on the several parameters (Choroidal thickness; CT, Choroidal vascularity index; CVI, Central macular thickness; CMT, The number of intravitreal injections) and CC flow voids.

RESULTS

The CC flow void increased sequentially: The uninvolved quadrant of acute BRVO-affected eyes, that of resolved eyes after 3-month/1-year, the contralateral quadrant of fellow eye, the involved (occluded) quadrant of resolved eyes. There were significant correlations between initial CMT, the number of injections and the CC flow void of uninvolved quadrants (P = 0.025, 0.031, respectively), and between the involved (occluded) quadrants and fellow CT (P = 0.029).

CONCLUSION

CC flow void of uninvolved macular areas decreased significantly in eyes with acute BRVO, suggesting that CC changes were limited to the blocked area and a compensatory mechanism would work in surrounding areas.

[Biomarkers in the treatment of retinal vein occlusion]

BACKGROUND

Retinal vein occlusion, subdivided into central retinal and branch retinal vein occlusion, is one of the most frequent vascular diseases of the retina. Biomarkers of optical coherence tomography (OCT), OCT-angiography and (ultra-widefield) fluorescein angiography are of exceptional importance in the initial diagnosis and also in the treatment of complications associated with retinal vascular occlusion, particularly macular edema.

METHODS

A systematic literature review was carried out in PubMed with the keywords central retinal vein occlusion, branch retinal vein occlusion, biomarker, OCT, OCT angiography, ultra-widefield fluorescein angiography with prioritization of the most important aspects.

RESULTS

Relevant biomarkers in OCT include central retinal thickness (CRT), macular fluid, the integrity of the photoreceptor bands (external limiting membrane and ellipsoid zone), disorganization of retinal inner layers (DRIL), hyperreflective foci, choroidal thickness and signs of ischemia, such as a prominent middle limiting membrane (p-MLM), paracentral acute middle maculopathy (PAMM) as well as hyperreflectivity of inner retinal layers (HIRL). The importance of OCT-angiography lies particularly in the assessment of microvascular alterations, especially vessel density in the deep retinal vascular plexus, the foveal avascular zone and of areas with no capillary perfusion. Biomarkers of ultra-widefield angiography, such as peripheral ischemia (ischemic index) and neovascularízation are essential with respect to treatment decisions for retinal laser.

CONCLUSION

A multitude of simple and complex biomarkers currently enable an effective individualized evaluation of treatment and prognosis in retinal vein occlusion. A shift from invasive to noninvasive biomarkers can be observed.

Three-Dimensional Analysis of Choroidal Vessels in the Eyes of Patients With Unilateral BRVO

Purpose

To investigate the three-dimensional analysis of choroidal vascular changes in eyes with monocular branch retinal vein occlusion (BRVO) using swept-source optical coherence tomography (SS-OCT).

Methods

Twenty two unilateral BRVO patients with superior-temporal branch retinal vein occlusion and 27 healthy eyes were analyzed retrospectively. OCT and OCT angiography (OCTA) images of 12 * 12 mm centered on the foveal of each eye were analyzed. Three-dimensional choroidal vascularity index (CVI), choroidal thickness, and choriocapillaris density were compared among BRVO eyes, fellow eyes, and healthy control eyes. En face CVI maps in BRVO eyes were generated to analyze the dilatation pattern of choroidal vessels.

Results

CVI values in a few 1 * 1 mm grids in the non-affected hemi side were higher in BRVO eyes compared with the fellow eyes and control eyes (p < 0.05). Choriocapillaris density decreased in both BRVO eyes and fellow eyes compared with normal eyes while choriocapillaris density was higher in a few grids in the non-affected hemi side in BRVO eyes compared with fellow eyes (p < 0.05). Choroidal dilatation pattern was categorized into four types and inferior choroidal dilatation and posterior pole choroidal dilatation were the major types.

Conclusion

Three-dimensional CVI tended to increase in non-affected hemi side and choroidal vessels tended to dilate in adjacent areas in BRVO eyes. Choriocapillaris density decreased in both eyes of monocular BRVO patients. The choroidal changes suggested that choroidal redistribution occurred in BRVO.