Abstract
Purpose :
Optical coherence tomography angiography (OCT-A) has been shown to identify flow voids in the choriocapillaris and choroid in the acute phase of VKH which correspond to hypo-fluorescent spots on Indocyanine Green Angiography (ICGA).1,2 The purpose of this retrospective, cross sectional study was to compare the sensitivity of OCT-A at detecting flow voids to ICGA and choroidal thickness by EDI OCT in patients with convalescent or chronic VKH treated for various durations.
1. Aggarwal et al. The role of OCT-angiography in the diagnosis and management of acute Vogt-Koyanagi-Harada disease. Ocul Immun Inflamm 2018; 26(1): 142-153
2. Wintergerst MWM et al. OCT-angiography for evaluation of Sattler’s layer in Vogt-Koyanagi-Harada Disease. Ophthalmic Surg Lasers Imaging Retina 2018; 49: 639-642
Methods :
This retrospective Institutional Review Board (IRB) approved study was conducted at the Bascom Palmer Eye Institute of the University of Miami. Patients with convalescent or chronic VKH (on systemic immune suppression more than one year after onset) who had same day imaging by EDI OCT, ICGA, and OCT-A between 7/1/18 and 11/23/18 were eligible for inclusion. Pathologic changes were defined as sub-foveal choroidal thickness greater than 300 microns by EDI OCT, hypo-fluorescent spots on ICGA, and flow voids in the choriocapillaris and choroid on OCT-A.
Results :
Sixteen eyes of eight patients were included in the analysis. EDI OCT demonstrated choroidal thickening in twelve eyes (75%), ICGA demonstrated hypo-fluorescent spots in sixteen eyes (100%), and OCT-A showed flow voids in fifteen eyes (94%). When co-utilizing modalities, twelve eyes (75%) showed abnormalities on EDI and ICGA, eleven eyes (69%) showed abnormalities on EDI and OCT-A, and fifteen eyes (94%) showed abnormalities on ICGA and OCT-A.
Conclusions :
OCT-A flow voids roughly co-localized to areas of ICG hypo-fluorescence which may indicate prior damage rather than active disease in patients receiving immune suppressive therapy in chronic or convalescent VKH. Longitudinal studies correlating changes in immunosuppressive therapy and clinical impression of uveitis activity would help determine whether flow voids on OCT-A represent residual choroidal inflammation in VKH.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.