Alterations in the Ocular Surface and Corneal Subbasal Nerve Plexus Following Various Retinal Surgical Procedures: A One-Year Confocal Microscopy Prospective Study.

Abstract

To evaluate the effects of retinal surgery on the ocular surface and corneal subbasal nerve plexus (SNP). Ninety-eight patients undergoing 23-gauge pars plana vitrectomy for various vitreoretinal disorders were prospectively studied. We collected detailed operative and perioperative data, measuring dry eye syndrome (DED) severity and Ocular Surface Disease Index (OSDI) scores before surgery and at postoperative intervals. In vivo confocal microscopy (IVCM) quantified SNP and dendritic cell (DC) densities. Fifty-three patients were analyzed. Post-surgery, OSDI scores rose from a baseline of 5.5 ± 3.5 to 12.24 ± 6.5 at one month, later reducing to 7.8 ± 4.0 after a year. DED severity increased from 0.6 ± 0.6 initially to 1.6 ± 0.6 at three months, returning to near baseline (0.9 ± 0.6) one year after surgery. DC densities increased notably by the third (58.85 ± 75.6 cells/mm²) and ninth (59.95 ± 86 cells/mm²) postoperative months, especially in patients undergoing combined phacoemulsification, vitrectomy, and C3F8 gas tamponade. SNP parameters, particularly nerve fiber density and length, showed significant declines one month post-surgery, not recovering to baseline levels within a year. Fiber density dropped from 19.06 ± 8.3 fibers/mm² preoperatively to 4.68 ± 4.8 fibers/mm² at one month, partially recovering to 10.64 ± 8.2 fibers/mm² at twelve months. Fiber length decreased from 13.31 ± 3.2 mm/mm² to 6.86 ± 3.4 mm/mm² at one month, later improving to 9.81 ± 4.5 mm/mm² at twelve months, notably in patients with silicone oil (SiO2) tamponade. Retinal surgery, especially when combined with phacoemulsification and C3F8 or SiO2 tamponade, significantly affects ocular surface integrity and SNP density, with these changes lasting up to a year. Expanded studies with more patients and longer follow-up, using finer 25- and 27-gauge vitrectomy tools, are recommended to confirm and extend these findings.