SPATIAL DISTRIBUTION OF CHORIOCAPILLARIS IMPAIRMENT IN EYES WITH CHOROIDAL NEOVASCULARIZATION SECONDARY TO AGE-RELATED MACULAR DEGENERATION: A Quantitative OCT Angiography Study. Issue 3 (March 2020)

• Record Type: Journal Article
• Authors: Moult, Eric M.; Alibhai, Agha Yasin; Rebhun, Carl; Lee, ByungKun; Ploner, Stefan; Schottenhamml, Julia; Husvogt, Lennart; Baumal, Caroline R.; Witkin, Andre J.; Maier, Andreas; Duker, Jay S.; Rosenfeld, Phillip J.; Waheed, Nadia K.; Fujimoto, James G.
• Is Part Of: Retina. Volume 40:Issue 3(2020)
• Publication Date: 2020-03
• Subjects: choriocapillaris -- CNV -- OCTA -- AMD -- blood flow -- choroid; Retina -- Diseases -- Periodicals; Retinal Diseases; Vitreous Body; 617.735
• DOI: 10.1097/IAE.0000000000002556
• Languages: English
• ISSNs: 0275-004X

Abstract

Abstract : Purpose: To develop an optical coherence tomography angiography (OCTA)-based framework for quantitatively analyzing the spatial distribution of choriocapillaris (CC) impairment around choroidal neovascularization (CNV) secondary to age-related macular degeneration. Methods: In a retrospective, cross-sectional study, 400-kHz swept-source OCTA images from 7 eyes of 6 patients with CNV secondary to age-related macular degeneration were quantitatively analyzed using custom software. A lesion-centered zonal OCTA analysis technique—which portioned the field-of-view into zones relative to CNV boundaries—was developed to quantify the spatial dependence of CC flow deficits. Results: Quantitative, lesion-centered zonal analysis of CC OCTA images revealed highest flow-deficit percentages near CNV boundaries, decreasing in zones farther from the boundaries. Optical coherence tomography angiography using shorter (1.5 ms) interscan times revealed more severe flow deficits than OCTA using longer (3.0 ms) interscan times; however, spatial trends were similar for both interscan times. A detailed description of the OCTA processing steps and parameters was provided so as to elucidate their influence on quantitative measurements. Conclusion: Impairment of the CC, assessed by flow-deficit percentages, was most prominent closest to CNV boundaries. The lesion-centered zonal analysis technique enabled quantitative CC measurements relative to focal lesions. Understanding how processing steps, imaging/processing parameters, and artifacts can affect quantitative CC measurements is important for longitudinal, OCTA-based studies of disease progression, and treatment response. Abstract : Supplemental Digital Content is Available in the Text.Using quantitative, spatially resolved analysis, this study found choriocapillaris flow impairment surrounding choroidal neovascularization secondary to age-related macular degeneration. An extensive discussion of image processing steps and parameters is also presented with the aim of reducing misinterpretations and mitigating artifacts.