Lid wiper epitheliopathy and ocular surface dysfunction in benign essential blepharospasm before and after botulinum toxin-A injection.

[OBJECTIVE] To investigate ocular surface dysfunction in patients with benign essential blepharospasm (BEB) by evaluating lid wiper epitheliopathy (LWE) and ocular surface parameters and to compare these findings with those of normal and dry eye controls. Additionally, we aimed to assess the impact of botulinum toxin (BTX-A) injection on ocular surface parameters and LWE.

[METHODS] This study included BEB patients and age- and sex-matched healthy and dry-eye controls. LWE grading and ocular surface parameters were assessed, including OSDI score, Schirmer's I test, tear break-up time (TBUT), corneal staining, eyelid margin abnormalities, and meibomian gland function. Patients with BEB received BTX-A injections, and measurements were repeated 1, 3, and 6 months post-treatment.

[RESULTS] Compared to control groups, the BEB group exhibited significantly increased OSDI scores, corneal surface staining, eyelid margin abnormalities, meibomian expression, meibography scores, meibomian gland loss, and LWE grades of the upper and lower eyelid (p < 0.05) while TBUT and Schirmer's I test values were significantly decreased (p < 0.05). Significant positive correlations were observed between the severity and frequency of BEB and ocular surface dysfunction, including LWE (p < 0.05). LWE severity was significantly correlated with age, female gender, and ocular surface parameters (p < 0.05). BTX-A injection significantly improved ocular surface parameters for 6 months, but LWE reduction was insignificant at 6 months (p < 0.05).

[CONCLUSION] LWE was identified as a significant contributor to conjunctivocorneal damage in BEB. Furthermore, BTX-A injection effectively treats ocular surface dysfunction, including LWE.