Corneal Tissue Parameters Correlate With CCT Change Following Short-Term CL Wear

Corneal tissue parameters measured before contact lens wear correlate with central corneal thickness (CCT) changes following a brief period of lens wear, according to research published in Ophthalmic and Physiological Optics. Theses parameters, however, are independent of corneoscleral parameters prior to and following contact lens wear, according to the report.  

Researchers examined ocular surface changes among a cohort of 22 healthy individuals (mean age, 21.0 years; women, 18) prior to inserting silicone hydrogel contact lenses and following their removal at 8 hours. The team performed corneal tomography, corneoscleral topography, CCT measurements and evaluated limbus position, corneoscleral junction [CSJ] angle, corneal transparency, and homogeneity before and after lens wear. The investigation’s objective was to determine the effect of short-term contact lens wear on corneoscleral and corneal tissue parameters.

The corneoscleral parameters (limbus position and CSJ angle) were independent of corneal tissue parameters (transparency and homogeneity) at baseline and following contact lens wear, according to the report. Transparency and homogeneity, however, demonstrated a moderate correlation with CCT following the short-term period of contact lens wear (r=−0.51; P =.007 and r=−0.46; P=.02, respectively). Aside from CCT changes, the brief contact lens wear period did not affect any other corneal shape parameters, including flattest keratometry, steepest keratometry, corneal astigmatism, and white-to-white measurements.

“[T]he results suggest that investigating baseline corneal densitometry might help to predict the hypoxic corneal response associated with [contact lens] wear,” according to the researchers. “[T]o understand the changes occurring on the ocular surface due to [contact lens] wear, it is valuable to examine both corneoscleral topography
and corneal densitometry concurrently. These two factors provide complementary information and contribute to a comprehensive characterization of the ocular surface
changes following CL wear.”

Study limitations include a small sample size and failure to determine the repeatability of corneal tissue parameter measurements.