Choroidal vascularity index and choroidal thickness assessment in vitiligo

Abstract

Clinical relevance: Vitiligo is a skin disease characterised by depigmentation and loss of melanocytes. Melanocyte loss may not be limited to the skin in vitiligo, and various abnormalities may occur in the choroid, which is dense in melanocytes. Background: To evaluate structural changes in the choroid by measuring choroidal thickness and vascularity index using optical coherence tomography in patients with vitiligo and comparing them to healthy subjects. Methods: This study included 168 participants: 84 with vitiligo (30 females, 54 males) and 84 controls (36 females, 48 males). Choroidal thickness and vascularity index were measured using the enhanced depth imaging mode in spectral-domain optical coherence tomography. The choroidal thickness was measured at the following five points; subfoveal (SF), 500 μm (NCT1) and 1000 μm (NCT2) nasal to the fovea; and 500 μm (TCT1) and 1000 μm (TCT2) temporal to the fovea. The choroidal vascularity index was calculated using the ImageJ software. Results: SF (p < 0.001), NCT1 (p < 0.001), NCT2 (p = 0.021), TCT1 (p = 0.001), and TCT2 (p < 0.006) choroidal thicknesses were significantly smaller in the vitiligo group than in the control group. Total choroidal (p < 0.001) and stromal (p < 0.001) areas were significantly smaller in the vitiligo group than in the control group. Choroidal vascularity indices were significantly higher in the vitiligo group than in the control group (p < 0.001). However, luminal areas did not differ significantly between groups (p = 0.935). Conclusion: Patients with vitiligo should be regularly monitored for choroidal alterations and, if necessary, referred to an ophthalmologist. © 2023 Optometry Australia.