Evaluation of corneal microstructure in keratoconus: a confocal microscopy study

Area of Science:

• Ophthalmology
• Corneal Science
• Confocal Microscopy

Background:

• Keratoconus (KCN) is a progressive thinning disorder of the cornea.
• Early detection of KCN is crucial for timely intervention.
• Corneal microstructure alterations may precede clinical diagnosis.

Purpose of the Study:

• To compare corneal microstructure in manifest KCN, subclinical KCN, KCN relatives, and healthy controls.
• To identify potential biomarkers for early KCN detection using in vivo confocal microscopy.

Main Methods:

• Prospective and cross-sectional study involving 145 subjects.
• Participants categorized into manifest KCN (n=30), subclinical KCN (n=32), KCN relatives (n=53), and control (n=30) groups.
• Corneal microstructure assessed via in vivo confocal microscopy, measuring cell densities and nerve parameters.

Main Results:

• Lower anterior and posterior stromal keratocyte densities observed in manifest KCN, subclinical KCN, and relatives compared to controls (P < 0.001).
• Higher stromal nerve diameter found in manifest KCN, subclinical KCN, and relatives versus controls (P ≤ 0.004).
• No significant differences in basal epithelial cell density, endothelial cell density, or sub-basal nerve diameter among groups.

Conclusions:

• Reduced stromal keratocyte densities and increased stromal nerve diameter are indicative of KCN, even in subclinical stages and among relatives.
• In vivo confocal microscopy can detect early microstructural corneal changes preceding overt topographic signs of KCN.