VEGF and axial length (RVU)
Reviewed by Saruban Pasu

The authors of this paper set out to examine whether the concentrations of VEGF in the vitreous were associated with refractive error and axial length in eyes without retinal disease, except of macular holes or epiretinal membranes. A vitreous sample was obtained during 23-gauge pars plana vitrectomy on 34 patients (21 macular holes, 13 epiretinal membranes). Mean age was 62.4, mean IOP was 13.8, mean spherical equivalent was -3.26 +/- 4.23 dioptres (range, -17.50 to 1.50D) and mean axial length was 24.1 +/-1.8mm (range, 21.0 – 29.1mm). The intravitreal VEGF concentration was significantly lower than the VEGF concentration in the blood. Intravitreal VEGF concentrations were not significantly associated with gender or age. A higher intravitreal VEGF concentration was significantly associated with a shorter axial length and a higher hyperopic refractive error. Plasma concentrations of VEGF were not significantly associated with axial length or refractive error. These results are consistent with other studies showing that aqueous humour concentrations of VEGF were significantly and negatively correlated with axial length. The results of this study fit with the observations made in population-based and hospital-based studies that myopia is associated with the lower prevalence of exudative age-related macular degeneration, proliferative diabetic retinopathy, and branch retinal vein occlusion. VEGF may be more diluted in the larger vitreous cavity of eyes with a longer axial length than in the smaller vitreous cavity of eyes with a shorter axial length. 

Intravitreal vascular endothelial growth factor concentration and axial length.
Hu Q, Liu G, Deng Q, et al.
RETINA
2015;35(3):435-9.