Prevalence of Dry Eye Disease and Ocular Surface Abnormalities in Eyes with Corneal Transplantation: A Cross-Sectional Study.

Purpose: To evaluate tear film and ocular surface parameters and estimate the prevalence of dry eye disease (DED) in eyes following corneal transplantation. Patients and Methods: This cross-sectional study assessed 104 eyes of 81 patients who had undergone penetrating keratoplasty (PK; 81 eyes), deep anterior lamellar keratoplasty (DALK; 9 eyes), or endothelial keratoplasty (EK; 14 eyes) for ≥ 3 months. Comprehensive ocular surface evaluations included the Ocular Surface Disease Index (OSDI), tear osmolarity, tear meniscus height (TMH), fluorescein tear breakup time, Oxford fluorescein staining, eyelid margin morphology, Schirmer I test, meibomian gland expressibility, and meibum quality. Results: Among post-PK/DALK eyes, more than 50% demonstrated at least one significant ocular surface abnormality, whereas this was observed in at least 25% of post-EK eyes. Elevated tear osmolarity was detected in approximately 20% of eyes in both groups. Based on TFOS DEWS II criteria, 32% of post-PK/DALK eyes and 57% of post-EK eyes met the diagnostic threshold for DED. Post-PK/DALK eyes with a follow-up time of ≤ 6 months exhibited significantly higher Oxford staining scores compared to those with follow-up > 6 months (P = 0.011). In unilateral PK/DALK cases, operated eyes showed greater ocular surface staining (P < 0.001) and a greater proportion of tear hyperosmolarity (P = 0.001) compared to unoperated fellow eyes. Conclusion: DED is common after corneal transplantation. While more pronounced in the early postoperative period, ocular surface epitheliopathy may persist long-term after surgery. These findings underscore the need for proactive long-term ocular surface monitoring and management to optimize surgical outcomes.