Artificial Tear Instillation-Induced Changes in Corneal Topography.

Area of Science:

• Ophthalmology
• Corneal topography
• Dry eye disease management

Background:

• Dry eye disease (DED) affects millions globally, causing discomfort and visual disturbances.
• Corneal topography is crucial for assessing ocular surface health and refractive status.
• The impact of artificial tears on corneal topography in DED patients requires further investigation.

Purpose of the Study:

• To compare corneal topography changes before and after artificial tear instillation in DED patients.
• To evaluate the effects of two specific artificial tear formulations: 1% polysorbate 80 (PSB) and 0.5% carboxymethylcellulose (CMC).

Main Methods:

• Corneal topography was measured using the Galilei G4 system, 1 minute before and after artificial tear instillation.
• 135 DED patients participated, receiving either PSB (101 eyes) or CMC (34 eyes).
• Key metrics analyzed included Sim K values and astigmatic axis changes.

Main Results:

• A significant increase in average Sim K values was observed post-instillation (44.07 D vs. 43.90 D, p=0.006).
• Mean Sim K astigmatism increased significantly after PSB instillation (1.48 D vs. 1.31 D, p=0.049).
• Significant astigmatic axis shifts (≥10° in 51.9%, ≥30° in 20.0% of patients) occurred post-instillation. PSB demonstrated a more pronounced effect on keratometry than CMC.

Conclusions:

• Artificial tear instillation causes measurable changes in corneal topography, including Sim K values and astigmatic axis, in DED patients.
• The formulation of artificial tears influences the degree of topographical alteration.
• PSB appears to have a greater impact on corneal keratometry compared to CMC.