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Published on: August 2, 2024
Ocular involvement in facial nerve paralysis: risk factors for severe visual impairment and ocular surface exposure
S Singh1,2, A V Das3, Mohammad Hasnat Ali4
1Ophthalmic Plastic Surgery Services, L V Prasad Eye Institute, Hyderabad, India.
Purpose:
To identify the risk factors associated with the development of ocular surface exposure and severe visual impairment (SVI) in patients with facial nerve palsy (FNP).
Methods:
Ocular data of all consecutive FNP patients (N = 1870) presenting to an eye-care network over the past 10 years were reviewed. Risk factors associated with SVI (best-corrected visual acuity <20/200) and ocular surface exposure at presentation were evaluated using multivariate analysis and odds ratios (OR).
Results:
The prevalence of SVI was 15%, and 47% had ocular surface exposure at the first presentation. The presence of corneal scar (28% vs. 10.2%, p < .001; OR 3.05), corneal ulcer (12.9% vs. 2.3%, p < .001; OR 4.67), older age at presentation (p < .001; OR 1.02), >10 mm lagophthalmos (p < .001; OR 8.7), male sex, and duration of FNP (p = .021; OR 1) were independent risk factors for developing SVI. Of the 893 eyes with ocular surface exposure, 75 (3.9%) had a corneal ulcer, and 11 (0.6%) were perforated, with the rest having epithelial defects and punctate keratopathy. Patients with neoplastic etiology (15.9% vs. 5.7%; p < .001; OR 2.39), lagophthalmos (49% vs. 29.7%; p < .001; OR 2.25) and poor Bell's phenomenon (9.4% vs. 4.2%; p = .005; OR 1.8) had twofold risk for developing ocular surface exposure.
Conclusion:
Eyes with lagophthalmos, poor Bell's phenomenon, and FNP of neoplastic etiology have a higher risk of developing ocular surface exposure. Male sex, increasing age, longer duration of FNP, and >10 mm lagophthalmos are associated with SVI in FNP patients; hence, early and timely intervention is necessary.
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