Ocular surface homeostasis instability in acoustic neuroma: corneal nerve density reduction and blink reflex abnormalities.

PURPOSE

To assess the condition of the ocular surface and electrophysiology in patients diagnosed with acoustic neuroma.

METHODS

For this prospective case-control observational study, twenty-nine patients diagnosed with acoustic neuroma and eleven healthy individuals were included. All participants underwent a comprehensive ophthalmic assessment, including assessment of corneal sensitivity, morphologic examination of cornea nerves using in vivo confocal microscopy (IVCM), and electrophysiology evaluation.

RESULTS

In a cohort of 29 patients diagnosed with acoustic neuroma, 48.3% (n = 14) were male, with an average age of 49.10 ± 11.82 years. Conversely, within the group of 11 healthy participants, 54.5% (n = 6) were male, with an average age of 44.64 ± 8.14 years. The ST I and TFBUT exhibited decreased values in the ipsilateral eyes of patients with acoustic neuroma compared to the contralateral eyes (ST I: 8.25 [1.00, 30.00] vs. 10.35 [1.00, 30.00], P = 0.011; TFBUT: 4.70 [2.00, 15.00] vs. 6.35 [2.00, 15.00], P = 0.029). Furthermore, the ST values of acoustic neuroma negatively correlated with Hannover classification (β: -9.14 [-18.09, -0.18], P = 0.046). In terms of blink reflex electrophysiology, the latency of R1 and R2 waves on the ipsilateral side was prolonged compared to the contralateral sides (P < 0.05).

CONCLUSIONS

This study sheds light on the ocular manifestations of acoustic neuroma with a significant reduction in ST I values and TFBUT. This can be attributed to a decrease in the density of central corneal nerve and a change in blink reflex electrophysiology with a prolonged latency of R1 & R2 waves on the ipsilateral side.