Choroidal vascularity index in pseudoexfoliation syndrome: a review of the literature

Choroidal thickness and choroidal vascularity index (CVI) appear to be distorted in eyes with pseudoexfoliation (PEX) syndrome. The accumulation of exfoliation material in the inner wall of choroidal vessels has led to the hypothesis that CVI may be affected both in glaucoma patients and individuals suspected of having glaucoma. The use of the optical coherence tomography (OCT) over the past few decades has facilitated the thorough and noninvasive examination of the posterior segment, whereas recent breakthroughs in technology have provided a more in-depth analysis of the choroidal vasculature with the introduction of swept-source (SS) OCT, enhanced-depth imaging (EDI) OCT, en-face OCT, and OCT angiography (OCTA). Choroidal thickness (CT) is a useful tool in clinical research as an indicator of ocular and systemic health. Reduced CT may cause retinal hypoxia and be responsible for the retinal nerve fiber layer (RNFL) abnormalities in PEX syndrome. The choroidal blood flow is probably not affected until the PEX material clinically appears in the intraocular structures. Future studies with a larger number of patients, especially unilateral PEX syndrome, and longer follow-up periods need to be carried out in order to shed more light on the association between PEX syndrome and ocular blood flow and choroidal thickness.