Dry eye outcomes after endonasal dacryocystorhinostomy: tear film changes and risk factors for symptom deterioration.

PURPOSE: To evaluate postoperative changes in tear film, ocular surface, and meibomian gland parameters following successful endonasal dacryocystorhinostomy (en-DCR) and predictive factors in postoperative dry-eye symptom deterioration in patients with primary acquired nasolacrimal duct obstruction (PANDO). STUDY DESIGN: Single-center prospective observational study. METHODS: This study included 50 patients with unilateral PANDO who underwent successful en-DCR. Tear film break-up time (TFBUT), Schirmer test, tear meniscus height (TMH), meibomian gland parameters, and dry eye-related symptoms were assessed preoperatively and 3 months postoperatively. Measurements were compared between affected and unaffected eyes, and between pre- and postoperative visits. Patients were categorized into unchanged/improvement or deterioration groups based on postoperative symptom changes. Multivariate logistic regression was performed to identify risk factors for postoperative deterioration. RESULTS: Postoperatively, the affected eyes demonstrated significant reductions in TFBUT, Schirmer values, and upper and lower TMH, while the fellow eyes remained unchanged. Meibomian gland function significantly improved after surgery. Subjective dry eye symptoms remained unchanged or improved in the majority of the patients. However, 15 patients (30.0%) experienced postoperative symptom deterioration. Patients in the deterioration group had significantly longer preoperative TFBUT and lower DEQS scores. Multivariate analysis showed that lower preoperative upper TMH tended to be associated with an increased risk of postoperative symptom deterioration. CONCLUSIONS: Restoration of lacrimal drainage by en-DCR was associated with significant postoperative changes in tear film and ocular surface parameters, together with improvement in meibomian gland function. Lower preoperative upper TMH may be a potential risk factor for postoperative worsening of dry eye symptoms.