Corneal innervation changes ın Alzheimer's: implications for sensory dysfunction.

Area of Science:

• Ophthalmology
• Neurology
• Medical Diagnostics

Background:

• Alzheimer's disease (AD) is a progressive neurodegenerative disorder.
• Corneal nerves play a role in sensory function and ocular health.
• Investigating peripheral nerve changes may offer insights into systemic neurological conditions.

Purpose of the Study:

• To compare corneal subbasal nerve plexus (CSNP) parameters and corneal sensitivity between AD patients and healthy controls.
• To assess the potential of corneal nerve changes as biomarkers for AD.

Main Methods:

• A cross-sectional study involving 22 AD patients and 18 healthy controls.
• In vivo confocal microscopy used to measure CSNP parameters: nerve fiber length (NFL), nerve fiber density (NFD), and nerve branch density (NBD).
• Cochet-Bonnet esthesiometer employed to evaluate corneal sensitivity.

Main Results:

• AD patients exhibited significantly lower NFL, NFD, and NBD compared to controls (p < 0.001 for all).
• Corneal sensitivity was also significantly reduced in the AD group (p < 0.001).
• These findings indicate a parallel decrease in corneal nerves and sensitivity in AD.

Conclusions:

• Corneal nerve damage and reduced sensitivity are significantly associated with Alzheimer's disease.
• Corneal nerve plexus assessment and sensitivity testing may serve as valuable tools for early AD diagnosis and monitoring.
• Ocular surface complications secondary to these neurodegenerative changes warrant clinical consideration.