Ocular Surface Findings in Patients with Surgery-Indicated Chronic Rhinosinusitis with Nasal Polyps: A Retrospective Study

Background/Objectives: Inflammation plays a central role in the pathophysiology of both chronic rhinosinusitis (CRS) and dry eye disease (DED), suggesting a possible link between these two conditions. This study aimed to investigate the relationship between surgery-indicated chronic rhinosinusitis with nasal polyps (CRSwNP) and ocular surface parameters related to dry eye disease and to evaluate their association with radiological disease severity. Methods: This retrospective study included 32 patients with surgery-indicated CRSwNP who underwent functional endoscopic sinus surgery (January 2021–January 2025) and 31 controls, all of whom had complete ophthalmological examinations. Ocular surface parameters, including Ocular Surface Disease Index (OSDI) scores, tear break-up time (BUT), Schirmer test values, and Oxford staining scores, were compared between the groups. Disease severity was assessed using the Sino-Nasal Outcome Test-22 (SNOT-22) and the Lund–Mackay score (LMS). Generalized estimating equations (GEE) were used for eye-level analyses. Associations between ipsilateral LMS and ocular surface parameters, as well as the effects of the degree and location of sinus involvement, were also assessed. Results: Higher OSDI scores (p = 0.001), lower BUT and Schirmer test values, and higher Oxford staining scores were observed in the CRSwNP group (all p < 0.05). Ipsilateral LMS was not significantly associated with ipsilateral BUT, Schirmer test values, or Oxford staining scores. No association was observed between OSDI scores and either LMS or SNOT-22 scores. No sinus region, including the osteomeatal complex, showed a significant association after correction for multiple comparisons. Conclusions: Surgery-indicated CRSwNP is associated with objective ocular surface dysfunction, including impaired tear film stability and reduced aqueous tear secretion. However, ocular surface findings and dry eye symptoms were not related to radiological disease burden. These findings suggest that ocular surface evaluation may be considered in patients with surgery-indicated CRSwNP, but prospective studies are needed to confirm this.