The corneal thickness profile in different forms of glaucoma

Area of Science:

• Ophthalmology
• Corneal Physiology
• Glaucoma Research

Background:

• Glaucoma, a leading cause of irreversible blindness, is characterized by progressive optic nerve damage.
• Corneal thickness is a known risk factor for glaucoma, but its detailed profile in different glaucoma subtypes requires further characterization.
• Understanding corneal thickness variations may offer insights into glaucoma pathogenesis and progression.

Purpose of the Study:

• To comprehensively characterize the corneal thickness profile in primary high pressure (HPG) and normal pressure (NPG) open-angle glaucoma, and pseudoexfoliative glaucoma (PEXG).
• To investigate the influence of potential causative factors on these corneal thickness profiles.
• To compare corneal thickness parameters between glaucoma patients and healthy individuals.

Main Methods:

• Spatially resolved corneal thickness was measured using Pentacam HR and Corvis ST.
• Key parameters assessed included central corneal thickness (CCT), thinnest corneal thickness (TCT), and pachy slope.
• Peripheral pachymetry and differences between central and peripheral thickness were analyzed in 112 healthy subjects and 286 glaucoma patients.

Main Results:

• All glaucoma subgroups (HPG, NPG, PEXG) exhibited significantly reduced CCT, TCT, and pachy slope compared to healthy controls.
• Peripheral corneal thickness and the physiological increase from center to periphery were significantly lower in glaucoma patients.
• Corneal thinning parameters were associated with structural damage, disease duration, and the use of prostaglandin analogues.

Conclusions:

• Glaucoma is characterized by generalized corneal thinning, affecting both central and peripheral cornea.
• The typical increase in peripheral corneal thickness is diminished in all glaucoma subtypes.
• Observed associations suggest potential pathogenetic mechanisms linking corneal structure to glaucoma development and progression.