Corneal cross-linking biomechanics evaluated by a novel and easily implemented differential tonometry method
First Author: S.McCafferty USA
Co Author(s): M. Wang J. Berdahl
Evaluate corneal changes following corneal crosslinking (CCL) by paired differential tonometry intraocular pressure (IOP) measurements with a Goldmann tonometer (GAT) prism and corneal compensating, correcting applanation tonometry surface (CATS) prism.
Clinical prospective, open-label, randomized, controlled, reference device comparison
IOP was measured on 18 unique eyes undergoing CCL for keratoconus with a GAT using a standard flat GAT prism and a curved corneal error correcting CATS prism before treatment and at 2 weeks, 2 months and 6 months after treatment. Concurrent measurements of central corneal thickness (CCT) and corneal hysteresis (CH) were completed.
Paired IOP measurements with standard GAT and corneal correcting CATS prisms indicated a significant sustained relative increase in the differential IOP between the two prisms after CCL (p=0.005,0.015). CH initially decreased at two weeks post-CCL then returned to sustained pre-op levels (p=0.033,0.20). CCT progressively decreased following CCL (p=0.002).
Differential tonometry between standard GAT and corneal biomechanical compensating CATS prisms demonstrates it as a simple and sensitive method for measurement of changes in corneal rigidity and corneal stress redistribution.
has significant investment interest in a company producing, developing or supplying product or procedure presented