# Choroidal Vascularity Index in Adult-Onset Foveomacular Vitelliform Dystrophy: A Pilot Study
## 4 Discussion  
In this investigation we found that eyes with AOFVD presented a greater CVI than eyes with CD and controls. The major choroidal involvement was on the luminal component. To evaluate the possible role of the choroid in the pathogenesis of AOFVD, some authors evaluated CT in AOFVD with contrasting results. [PERSON] et al. reported choroidal thickening in AOFVD and suggested a different pathogenetic mechanism with respect to advanced dry and neovascular AMD, where choroidal thinning was observed [7]. Similarly to these results, [PERSON] et al. found increased subfoveal CT in patients with AOFVD compared to controls. These authors performed subgroup analysis of the different stages of disease (vitelliform, pseudohypopyon, and vitelliruptive) and did not find differences in CT between groups [10]. In contrast, [PERSON] et al. and [PERSON] et al. did not report a difference in CT between eyes with AOFVD and control subjects [8; 17]. However, these authors further analyzed CT in eyes with different stages of disease and found mean choroidal thickening in the vitelliruptive stage with respect to controls, indicating that CT changes may be stage-sensitive [8]. In order to account for any stage-sensitive bias, we only \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Feature** & **AOFVD N = 18** & **AMD N = 18** & **Controls N = 16** & \(p\) **Value** \\ \hline
**Luminal Area** & 1.05 \(\pm\) 0.39 & 0.83 \(\pm\) 0.27 & 0.77 \(\pm\) 0.26 & 0.04 \\
**Total area** & 1.46 \(\pm\) 0.48 & 1.25 \(\pm\) 0.43 & 1.12 \(\pm\) 0.36 & 0.07 \\
**CVI** & 0.71 \(\pm\) 0.04 & 0.68 \(\pm\) 0.03 & 0.69 \(\pm\) 0.02 & 0.004 \\
**SFCT** & 215.4 \(\pm\) 52.2 & 196.9 \(\pm\) 64.3 & 230.5 \(\pm\) 68.4 & 0.29 \\
**CT N 500** & 226.5 \(\pm\) 61.3 & 180.5 \(\pm\) 66.7 & 213.6 \(\pm\) 61.9 & 0.09 \\
**CT T 500** & 221.8 \(\pm\) 53.3 & 202.4 \(\pm\) 56.4 & 207.1 \(\pm\) 60.3 & 0.57 \\
**CT N 1500** & 210.1 \(\pm\) 68.9 & 155.7 \(\pm\) 70.9 & 213.5 \(\pm\) 74.6 & 0.04 \\
**CT T 1500** & 206.1 \(\pm\) 57.2 & 206.7 \(\pm\) 50.1 & 191.3 \(\pm\) 73.8 & 0.71 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Clinical features in adult-onset foveomacular vitelliform dystrophy (AOFVD) and age-related macular degeneration with conventional drusen. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Feature** & \multicolumn{2}{c}{**AOFVD**} & \multicolumn{2}{c}{**AMD**} \\  & \multicolumn{2}{c}{**N = 18**} & \multicolumn{2}{c}{**N = 18**} \\ \hline \hline \multirow{4}{*}{Luminal Area} & \multicolumn{2}{c}{\(p\) value} & \multicolumn{2}{c}{\(p\) value} \\ \cline{3-4}  & AMD & 0.05 & AOFVD: & 0.05 \\ \cline{1-1}  & Control & 0.02 & Control: & 0.63 \\ \cline{1-1}  & AMD & 0.001 & AOFVD: & 0.001 \\ \cline{1-1}  & Control & 0.03 & Control: & 0.25 \\ \hline \hline \end{tabular} Post-hoc test using least significant difference (LSD); AOFVD: adult-onset foveomacular vitelliform dystrophy; AMD: age-related macular degeneration.  
\end{table} 
Table 3: Post-hoc analysis of the different subgroups; adult-onset foveomacular vitelliform dystrophy (AOFVD) and age-related macular degeneration with conventional drusen. included the vitelliform type and, in accordance with [PERSON] et al. [9] and [PERSON] et al. [8], we did not find any difference in CT between eyes with AOFVD and control eyes. Recent studies using OCTA have shown CC vessel density reduction in patients with AOFVD [10,18,19]. [PERSON] et al. found reduced CC vessel density in the vitelliform stage and increased density in the vitelliruptive stage [10]. [PERSON] et al. examined enface OCTA images and reported vascular network rarefaction with reduced CC [19], indicating stage-sensitive variations in line with the progressive nature of vitelliform deposits. OCTA technology presented several advantages, especially in terms of image quality, acquisition time, and microvascular resolution, which allow proper estimation of the choriocapillaris flow impairment [20,21,22].