Neha Khandelwal

CHOROIDAL VASCULARITY INDEX: A Novel Optical Coherence Tomography Based Parameter in Patients With Exudative Age-Related Macular Degeneration.

Purpose: To evaluate choroidal structural changes in exudative age-related macular degeneration (AMD) using choroidal vascularity index computed from image binarization on spectral domain optical coherence tomography with enhanced depth imaging. Methods: This prospective case series included 42 consecutive patients with unilateral exudative AMD. Choroidal images were segmented into luminal area and stromal area. Choroidal vascularity index was defined as the ratio of luminal area to total choroid area. Mean choroidal vascularity index and mean choroidal thickness between study and fellow eyes of the same patient with dry AMD were compared using Students t-test. Results: There was a significantly lower choroidal vascularity index in eyes with exudative AMD (60.14 ± 4.55 vs. 62.75 ± 4.82, P < 0.01). Luminal area (P < 0.01) was decreased in eyes with exudative AMD but there was no significant difference in total choroid area (P = 0.05) and choroidal thickness (P = 0.93) between study and fellow eyes. Conclusion: Eyes with exudative AMD demonstrated reduced choroidal vascularity index but insignificant differences in choroidal thickness compared with their fellow eyes. Choroidal vascularity index may be a potential noninvasive tool for studying structural changes in choroid and monitoring choroidal disease in exudative AMD.

Choroidal Vascularity Index in Vogt-Koyanagi-Harada Disease: An EDI-OCT Derived Tool for Monitoring Disease Progression

Purpose We assessed the application of the choroidal vascularity index (CVI) in the follow-up of Vogt-Koyanagi-Harada disease (VKH) patients derived from image binarization of enhanced depth imaging optical coherence tomography (EDI-OCT) images with Fiji software. Our secondary objective was to derive the retinochoroidal vascularity index based on en face fundus fluorescein and indocyanine green angiography (FFA and ICGA). Methods In this retrospective cohort study, EDI-OCT scans of 18 eyes of 9 patients with VKH were obtained at baseline within 2 weeks of acute presentation, and again at 6 to 12 months. Images with poor quality were excluded. Choroidal thickness (CT) and CVI were analyzed and compared to 13 eyes of 13 healthy controls. En face FFA and ICGA obtained from 12 eyes of 7 patients were segmented to derive retinochoroidal vascularity index. Results There was no statistical difference in age or sex between the study group and controls. Choroidal thickness of patients with VKH was 359.23 ± 57.63 μm at baseline, compared to 274.09 ± 56.98 μm in controls (P = 0.003). Follow-up CT in VKH patients was 282.62 ± 42.51 μm, which was significantly decreased from baseline (P = 0.0001). Choroidal vascularity index in VKH patients was 70.03 ± 1.93% at baseline, compared to 64.63 ± 1.92% in controls (P < 0.001). Choroidal vascularity index was 66.94 ± 1.82% at follow-up, significantly reduced from baseline (P < 0.0001). Fundus fluorescein angiography and ICGA retinochoroidal vascularity indices at baseline were 70.67 ± 2.65% and 66.42 ± 2.16%, respectively. Conclusions In this small series of VKH patients, EDI-OCT–derived CVI had a statistically significant reduction over time, similar to CT. We propose that OCT, FFA, and ICGA-derived vascularity indices may be potential novel supportive tools in monitoring disease progression in VKH. Translational Relevance Choroidal vascularity index can be used potentially to study and analyze the structural changes in choroid. It can be a useful tool to explain the changes in the CT in different retinochoroidal disorders. Choroidal vascularity index also can be used for longitudinal follow-up in patients with VKH disease and other inflammatory disease involving the choroid.

Choroidal vascular changes in age-related macular degeneration

To assess the choroidal vascular changes using choroidal vascularity index (CVI) in patients with age‐related macular degeneration (AMD) compared to controls.

Choroidal Structural Changes in Myopic Choroidal Neovascularization After Treatment With Antivascular Endothelial Growth Factor Over 1 Year.

Purpose To evaluate choroidal structural changes in eyes with myopic choroidal neovascularization (mCNV) treated with anti-VEGF over 12 months. Methods We prospectively evaluated subfoveal choroidal thickness (SFCT) and choroidal vascularity index (CVI) using spectral-domain optical coherence tomography (SD-OCT) at baseline, 6, and 12 months in both eyes in patients presenting with unilateral mCNV. Choroidal vascularity index was defined as the ratio of luminal area to total choroidal area after SD-OCT images were binarized digitally. Results We included 20 patients (20 eyes with mCNV and 20 fellow eyes without mCNV) with mean age of 60.35 ± 10.85 years. At baseline, mean SFCT and CVI was similar between eyes with mCNV and fellow eyes (69.20 ± 63.04 μm vs. 67.10 ± 65.74 μm, P = 0.713 for SFCT and 59.44 ± 3.92% vs. 59.03 ±. 5.58%, P = 0.958 for CVI). Subfoveal choroidal thickness decreased significantly in the mCNV eyes to 54.75 ± 45.43 μm (P = 0.017) at 12 months after anti-VEGF therapy, whereas SFCT in the contralateral eyes did not change significantly. There was no significant change in CVI in mCNV eyes or contralateral eyes from baseline to 12 months. Thinning of SFCT did not influence final BCVA. Conclusions Thinning of subfoveal choroid without alteration in CVI was observed in eyes with mCNV treated with anti-VEGF therapy over 12 months. This finding may be explained by mechanical stretching in response to globe expansion.

Choroidal and Retinal Anatomical Responses Following Systemic Corticosteroid Therapy in Vogt–Koyanagi–Harada Disease Using Swept-Source Optical Coherence Tomography

ABSTRACT Purpose: To assess structural changes in retina and choroid after systemic corticosteroid therapy in Vogt–Koyanagi–Harada (VKH) disease using swept-source optical coherence tomography (SS-OCT). Methods: SS-OCT was conducted before treatment and during first-month follow-up in 16 eyes treated with systemic corticosteroids for active VKH. Retina was divided into five zones depending on pretreatment choroidal thickness (CT) of <100, >100 to <200, >200 to <300, >300 to <400 and >400μm, and changes in retinal thickness and CT after treatment in these zones were compared with baseline. Results: Mean CT significantly improved from 83.1±8.75 to 156.4±62.73μm(p = 0.008) in the zone with pre-CT <100μm and significantly decreased from 336.1 ± 17.28 to 266.28 ± 81.39μm(p = 0.008) in the zone with pre-CT > 300μm. Conclusions: We have shown choroidal remodeling in VKH. SS-OCT can serve as an important noninvasive tool in assessment of treatment response in patients with VKH disease.

Fluorescent Dye Labeling of Erythrocytes and Leukocytes for Studying the Flow Dynamics in Mouse Retinal Circulation

The retinal and choroidal blood flow dynamics may provide insight into the pathophysiology and sequelae of various ocular diseases, such as glaucoma, diabetic retinopathy, age-related macular degeneration (AMD) and other ocular inflammatory conditions. It may also help to monitor the therapeutic responses in the eye. The proper labeling of the blood cells, coupled with live-cell imaging of the labeled cells, allows for the investigation of the flow dynamics in the retinal and choroidal circulation. Here, we describe the standardized protocols of 1.5% indocyanine green (ICG) and 1% sodium fluorescein labeling of mice erythrocytes and leukocytes, respectively. Scanning laser ophthalmoscopy (SLO) was applied to visualize the labeled cells in the retinal circulation of C57BL/6J mice (wild type). Both methods demonstrated distinct fluorescently labeled cells in the mouse retinal circulation. These labeling methods can have wider applications in various ocular disease models.

Fluorescein Labeled Leukocytes for in vivo Imaging of Retinal Vascular Inflammation and Infiltrating Leukocytes in Laser-Induced Choroidal Neovascularization Model

ABSTRACT Purpose: To study the effect of anti-VEGF treatment on retinal inflammation in a laser-induced CNV rodent model. Methods: Leukocytes labeled with 1% sodium fluorescein were injected into the laser-induced CNV (wild type C57BL/6) mice at days 4 (baseline), 7, 14, and 19. At baseline intravitreally 3 mice received 1× PBS, and 3 mice received anti-VEGF. FFA, OCT, and SLO were performed at each time point to assess the CNV pathophysiology and inflammatory response. Results: Fluorescein leakage, SRF, and leukocyte infiltration were observed at baseline in both the groups before injection. From days 7 to 19, leukocyte infiltration and SRF were noted in the 1× PBS group, but limited or no SRF and leukocyte infiltration was observed in the anti-VEGF group. Conclusions: Leukocyte infiltration was established as an in vivo imaging inflammatory marker and along with FFA and OCT showed response to anti-VEGF therapy in laser-induced CNV model.

Choroidal Structural Changes in Tubercular Multifocal Serpiginoid Choroiditis

ABSTRACT Purpose: To assess choroidal vascular changes among patients with tubercular multifocal serpiginoid choroiditis (TB MSC) using previously validated techniques. Methods: Patients with TB MSC (n = 18) and healthy controls (n = 30) underwent enhanced-depth imaging optical coherence tomography (EDI-OCT) imaging. Using previously validated algorithm of image binarization, EDI-OCT scans were segmented to derive total choroidal area, luminal area, stromal area, and choroidal vascularity index (CVI). Results: There was a statistically significant difference in the CVI between controls (66.90 ± 1.77%) and TB MSC patients (65.46 ± 2.53%; p < 0.001). There was significant reduction in CVI at follow-up (3 months) (63.77 ± 3.91%; p = 0.05). The choroidal thickness was higher in TB MSC compared to controls (278.90 ± 57.84 µm versus 329.33 ± 27.69 µm; p = 0.001). Conclusions: CVI provides insight into structural changes in choroid in TB MSC. During the active disease, there is relative decrease in choroidal vascularity. As the lesions heal, choriocapillaris atrophy occurs with remodeling of choroid.

Choroidal vascularity index changes after vitreomacular surgery

To study the structural changes in the choroid using swept‐source (SS) optical coherence tomography (OCT), a tool for the choroidal vascularity index (CVI) following epiretinal membrane removal.

Choroidal structural analysis and vascularity index in retinal dystrophies

To assess choroidal structural changes in patients with retinal dystrophies using choroidal vascularity index (CVI), a novel optical coherence tomography (OCT) based tool.