Quantitative Analysis of the Choriocapillaris in Uveitis Using En Face Swept-Source Optical Coherence Tomography Angiography

Abstract

Purpose: To perform a quantitative analysis of choriocapillaris (CC) flow deficits (FDs) in patients with uveitis. Design: Retrospective cross-sectional studyMethods: Swept-source optical coherence tomography based angiography (SS-OCTA) macular volume scans (3×3 mm and 6×6 mm) were obtained using the PLEX® Elite 9000: En face CC images were generated and analyzed using an automated flow deficit identification algorithm. Three quantitative metrics were determined for each eye: FD number (FDN), mean FD size (MFDS), and FD density (FDD). Quantitative metrics were compared between uveitis and control eyes. The uveitis cohort was further subdivided by the presence or absence of choroidal involvement, and quantitative metrics were compared between subgroups and normal controls Results: A total of 38 eyes from 38 controls and 73 eyes from 73 uveitis subjects were included in this study. Eyes with uveitis have significantly larger CC MFDS (3×3 mm, p<0.0001; 6×6 mm, p<0.0001) and higher FDD (p=0.0002; p=0.0076) when compared to control eyes. Additional analysis determined that these differences are due to the choroidal disease subgroup, which demonstrates significantly larger MFDS (3×3 =1108 μm 2 ; 6×6 =1104 μm 2 ) compared to both normal controls (752 μm 2 , p<0.0001; 802 μm 2 , p<0.0001) and uveitis patients without choroidal involvement (785 μm 2 , p<0.0001; 821 μm 2 , p<0.0001). No significant differences were found between the quantitative metrics of controls and patients without choroidal involvement.Conclusions: Automated quantification of CC can identify pathological FDs and provide quantitative metrics describing such lesions in patients with uveitis. Posterior uveitis patients have significantly larger CC FDs than patients with other forms of uveitis.

Microvasculature Features of Vogt-Koyanagi-Harada Disease Revealed by Widefield Swept-Source Optical Coherence Tomography Angiography

“…Optical coherence tomography angiography is a new non-invasive imaging technique that can detect the movement of erythrocytes within blood vessels ( 9 ). Compared to spectral-domain OCT (SD-OCT), swept-source OCT (SS-OCT) is able to incorporate longer wavelengths (1,040 to 1,060 nm) and to simultaneously provide images of the vitreous, retina, and choroid ( 9 ), yielding high-resolution near-complete images of choroidal anatomy and CC perfusion ( 38 ). Therefore, SS-OCTA is a better imaging modality tool for detailed chorioretinal angiography than SD-OCTA.…”

Comparison of Indocyanine Green Angiography and Swept-Source Wide-Field Optical Coherence Tomography Angiography in Posterior Uveitis

“…OCTA has shown its advantage in the evaluation and management of retinal vascular diseases ( 7 , 8 ). OCTA allows better assessment of CC, which is displayed as dense and evenly spaced textures of capillaries distributed on a normal OCTA scan ( 9 – 11 ).…”

The use of optical coherence tomography angiography in comparing choriocapillaris recovery between two treatment strategies for multifocal choroiditis: a pilot clinical trial

“…In addition, we did not have automated measurements of CC FD in our study. With improvements in technology and application of quantitative algorithms, automated quantification is being increasingly employed [ 17 , 18 , 25 ]. In the future, such automated measurements may be applied to OCTA imaging of lesions of choroiditis as well.…”