Behcet's Uveitis analysis by TowardPi SS-OCTA

Behçet disease (BD) is a systemic disorder characterized by recurrent attacks of inflammation and vascular occlusion involving multiple systems. Behcet's Uveitis (BU) involves the entire fundus rather than the macula alone, a widefield fundus investigation is needed to fully and precisely describe its characteristics. Fluorescein angiography (FA) visualizes retinal vasculitis, but as a qualitative method, it can only display the superficial vascular plexus with limited value for delineating choroidal circulation. Indocyanine green fluorescence angiography (ICGA) images the choroidal vessels, whereas it cannot clearly visualize and quantify each layer of the choroid. Neither of these two invasive fundus imaging methods can simultaneously show and quantify the retina and choroid.

In this study, TowardPi SS-OCTA was utilized to visualize and quantify retinal and choroidal vessels for different scanning sizes including macula and peripheral regions. It was found that BU patients had enlargement of foveal avascular zone (FAZ) and decreased VD within a 300μm width around the FAZ. VD of choriocapillaris was lower in the peripheral fundus of BU compared to the controls. Fovea and peripheral fundus were prone to the damage of ischemia as evidenced by significantly decreased VD of capillaries.

“This technology has remarkably expanded our knowledge of the whole fundus through in vivo investigation of the anatomical and pathologic features of retinal and choroidal vascular layers.” Quote from “Analysis of Vascular Changes of Fundus in Behcet's Uveitis by Widefield Swept-source Optical Coherence Tomography Angiography and Fundus Fluorescein Angiography” published in <RETINA>

Fig1. Comparison of OCTA (L) and FA (R), patient with BU with a 5-year disease duration.

Fig2. SRV, DRV, CC, and LMVC layers blood flow quantification of BU（A, B）and normal subject (C).

Authors: Suo Guo, Hui Liu, Yu Gao, Lingyu Dai, Jing Xu, Peizeng Yang. The First Affiliated Hospital of Chongqing Medical University, China.

Link of abstract:

https://pubmed.ncbi.nlm.nih.gov/36729551/