Impact of Corneal Microbial Latency Detected by Metagenomic next-generation sequencing on Postoperative Recovery Following Keratorefractive lenticule extraction

Purpose: To investigate the microbial species latent in corneas of healthy individuals and determine whether small incision lenticule extraction (SMILE) serves as a risk factor for pathogen reactivation. Setting: The Ophthalmology Department of Peking University Third Hospital, Beijing, China. Design: Prospective Cohort Study. Methods: Metagenomic next-generation sequencing (mNGS) was employed to analyze the microbial composition of corneal lenticules from SMILE. Based on the results, patients were categorized into Viral Group (VG) and Non-Viral Pathogen Group (NVPG). Two Matched Groups (MG1 and MG2) were established by selecting pathogen-negative individuals at a 1:4 ratio relative to two positive groups. Using SPSS to analyze baseline characteristics, preoperative ocular parameters and postoperative ocular parameters among groups. Results: Among the detected pathogens, latent Herpesviruses were identified in 9 cases (4.31%), Papillomavirus were 4 cases (1.91%), and non-viral pathogens were 20 cases (9.57%). Both VG and NVPG groups showed no significant differences in baseline characteristics or preoperative ocular parameters compared with MG groups. In postoperative ocular parameters, no significant differences were found between VG and MG1, though intergroup variations in intraocular pressure and corneal thickness were observed (p>0.05). However, NVPG demonstrated significantly poorer results than MG2 in 1 month-spherical equivalent (p=0.033) and corneal epithelial staining (p=0.044). Conclusion: These findings indicate pathogen latency does not affect ocular status and SMILE surgery is unlikely to reactivate latent viruses or exerts minimal influence. Viral latency has almost no impact on postoperative recovery, while latent non-viral pathogens may interfere with postoperative recovery.