Purpose
To characterize the symptoms, signs and corneal innervation of patients with dry-eye-like symptoms but without dessicated signs, with the aid of laser in vivo cofocal microscopy.
Methods
Twenty-five eyes of 25 suspected corneal neuropathy patients, 24 eyes of 24 age- and sex- matched mild to moderate non-Sjogren’s syndrome dry eye patients (MMDE), and 24 healthy controls were recruited to the study. Ocular surface disease index (OSDI), visual analog scales (VAS), and Hospital Anxiety and Depression Scale (HADS) were used to assess subjective symptoms or psychological evaluation. Slit lamp examination, Schirmer I test (SIt), tear breakup time (TBUT), corneal fluorescein staining and laser in vivo confocal microscopy were conducted. The mechanical corneal sensitivity was measured using Cochet-Bonnet esthesiometer.
Results
the mean OSDI and VAS scores were higher in neuropathy and MMDE patients (P<0.001). The scores of both HADS anxiety and depression subscales among all the subjects were in normal range. The values of SIt (P=0.013) and tBUT (P<0.001) were lower in MMDE patients. The average corneal sensation thresholds for neuropathy patients was lower (P=0.003). the mean corneal nerve density, nerve counts, and LC density, were significantly higher in neuropathy group. The LC density, gender, average corneal sensitivity, and nerve density were independent factors for the OSDI or VAS scores.
Conclusions
Without dessicated signs, dry-eye-like symptoms could be caused only by corneal nerve alteration, immune reaction, and hypersensitivity, especially among female gender. Corneal neuropathy should be recognized instead of misclassified into suspected dry eye disease.
Keywords: 479 cornea: clinical science •
596 microscopy: confocal/tunneling