Vitreal concentrations of Vascular Endothelial Growth Factor in patients with Rhegmatogenous Retinal Detachment

Abstract

Purpose : The most prominent process resulting in anatomic failure after initial successful detachment surgery is proliferative vitreoretinopathy (PVR). It has been reported that tissues associated with PVR also have elevated levels of VEGF. However, our preliminary results in intravitreal injection of Bevacizumab in primary vitrectomy to decrease the rate of retinal redetachment showed neither a benefit nor any harm from intervention in both anatomic and visual outcomes. The results of our previous research prompted us to investigate whether VEGF levels are elevated in human RRDs and, if so, by how much compared to non-RRD conditions. We aimed to examine the vitreal VEGF concentration in patients with primary RRD by comparing the levels in cases with PVR A or B.

Methods : Undiluted vitreous sampling by vitrectomy probe was performed before opening the inflow port; sample volumes ranged 0.5-0.7ml and were immediately frozen and stored at -80°C. We also analyzed the vitreous VEGF level in 22 non-diabetic retinopathy patients who were candidate of 23-gauge PPV (Pars Plana Vitrectomy) due to Macular Hole (MH) or Epiretinal Membrane (ERM). We also analyzed the vitreous VEGF level in 21 fresh cadaveric globes. The vitreous samples were sent for analysis of VEGF level with ELISA microplate reader (DYNEX technologies, MRX microplate reader, USA).

Results : Eighteen patients with RRD and 22 samples of control and 21 fresh cadaveric globes enrolled in this study.The VEGF level in RRD group was statistically higher than control group (0.643 ± 0.088 Vs 0.043 ± 0.104, p < 0.001). The mean VEGF level in cadaveric group was similar to the control group (0.033 ± 0.058 Vs 0.043 ± 0.104, p > 0.05) .We did not find any statistically significant relation between the VEGF level and RRD extension (r=-0.365, P=0.147). Our data reveals that VEGF levels do not depend on the type or location of the breaks. This was explained by the fact that no variables, including break type (Hole or Horseshoe tear), break size (or number), or break extension, were statistically significant.

Conclusions : Our study showed that vitreous level of VEGF is significantly higher in patients with primary RRD than normal. It does not seem to be influenced by the break size or their numbers and may cast added information for future management of RRD and /or PVR.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.