Perfusion in the macula during closure of full-thickness macular hole with silicone tamponade

Background. Despite the development of new surgical techniques, silicone tamponade continues to be an important part of the surgical treatment for full-thickness macular hole (FTMH). However, there has been little research into the potential effect of silicone oil in the vitreous cavity on retinal blood flow in the macular area and functional recovery after surgery. Aim. To study changes in retinal blood flow in the postoperative period following closure of the FTMH using silicone tamponade. Materials and methods. The study included 40 patients (40 eyes) with stage 4 idiopathic FTMH, according to the classification of D. Gass. The patients were divided into two subgroups: 20 patients with silicone tamponade and 20 with gas tamponade. The OCT angiography method was used to study the area of the foveal avascular zone (FAZ), vascular density in the superficial and deep capillary plexus (SCP and DCP) in the fovea and parafovea, as well as the apical (minimum) diameter of the macular hole, the area of cystic changes in the inner nuclear and outer plexiform layers, and changes BCVA and retinal sensitivity (RS) at the fovea and parafovea levels. The studies were conducted before surgery and 2 and 6 months afterwards. Results. In the subgroup with silicone tamponade, two months after macular hole closure, there was a significantly lower vascular density in the SCP and the DCP in the fovea (p = 0.032 and p = 0.034, respectively), as well as a decrease in vascular density in these regions in the parafovea (p = 0.04 and p = 0.029, respectively). Additionally, there were lower mean values for the RS in both the fovea and the parafovea (p = 0.029 and p = 0.031, respectively). The change in the mean foveal and parafoveal RS correlates with changes in the vessel density in the DCP fovea and parafovea (r = 0.34 and r = 0,29 respectively, p<0.05) and with the vessel density in the SCP in the fovea (r = 0.33, p = 0.01), respectively. Conclusion. Silicone tamponade used in the treatment of FTMH may have a negative impact on macular perfusion, potentially slowing down or reducing the functional recovery of the retina during the early postoperative period.