Corneal thickness in trachomatous dry eye

Area of Science:

• Ophthalmology
• Corneal disease
• Dry eye disease

Background:

• Trachoma is a leading cause of preventable blindness globally.
• Scarring trachoma often leads to chronic dry eye disease due to severe ocular surface desiccation.
• Understanding corneal changes in trachomatous dry eye is crucial for managing visual impairment.

Purpose of the Study:

• To investigate the impact of severe desiccation on corneal thickness in individuals with scarring trachoma.
• To compare corneal thickness between normal corneas and those affected by trachomatous dry eye.

Main Methods:

• Ultrasonic pachymetry was employed to measure corneal thickness.
• Measurements were taken at nine distinct points across the central and peripheral cornea.
• The study included 27 patients with trachomatous dry eye and 31 healthy control subjects.

Main Results:

• Corneal thickness was significantly reduced in trachomatous dry eyes compared to normal eyes across central and midperipheral regions.
• The superior cornea was the thickest part in both groups, but thinner in trachomatous dry eyes (574.03±31.62 µm) versus normal (611.33±34.99 µm).
• The central cornea was the thinnest in both groups, with significantly less thickness in trachomatous dry eyes (510.43±32.12 µm) compared to normal (546.27±36.20 µm).

Conclusions:

• Patients with trachomatous dry eye exhibit significantly reduced corneal thickness in central and midperipheral areas.
• Chronic severe desiccation, tear film instability, and heightened immune responses in trachomatous dry eye likely contribute to corneal thinning.
• These findings highlight structural changes in the cornea associated with trachomatous dry eye, potentially impacting visual function.