The Prevalence of Corneal Sensitivity Loss in Patients with and without Dry Eye Disease.

Purpose: To assess the prevalence of corneal sensitivity loss in consecutive patients presenting to the clinic as well as in those patients with and without dry eye disease (DED).

Methods: Retrospective, single-center study of consecutive patients who presented to the eye clinic and underwent corneal sensitivity testing using a non-contact esthesiometer. Data included demographics, medical history, prior or current treatments, comorbidities, corneal sensitivity measurements, dry eye symptoms (Standard Patient Evaluation of Eye Dryness Questionnaire [SPEED] questionnaire), and corneal staining scores (Oxford scale). The primary outcome was the prevalence of corneal sensitivity loss, defined as ≥8 mbar. Secondary outcome measures included the prevalence of corneal sensitivity loss in eyes with DED (Oxford ≥2 and SPEED ≥5) and without DED (Oxford ≤1 and SPEED <5).

Results: A total of 395 eyes of 198 patients were included for analysis. Average age was 67.7 ± 16.0 years, and the majority of patients (60.6%) were female. Corneal sensitivity loss was observed in 9.4% of all eyes, and 12.6% of patients had reduced corneal sensitivity in at least one eye. When assessing eyes with signs of DED (Oxford ≥2), 19.7% (13/66) had corneal sensitivity loss. This prevalence increased to 31.4% (11/35) in eyes with both signs and symptoms of DED. Conversely, the prevalence was 5.5% (12/219) in eyes without DED. Binary logistic regression demonstrated that Oxford staining score was the strongest predictor of reduced corneal sensitivity (OR: 2.0, 95% CI: 1.3-3.0, p=0.001), with other significant factors including history of DED, stroke, and herpes zoster virus.

Conclusion: Reduced corneal sensation, a sign of corneal nerve damage and precursor to neurotrophic keratitis, affects nearly 10% of all eyes and 30% of eyes with signs and symptoms of DED. Routine clinical testing of corneal sensation should be implemented, particularly in patients with DED, to ensure early diagnosis and prompt treatment to prevent disease progression.