Novel Architecture for Laser Astigmatic Keratotomy: Validation of Patient-Specific Computational Modeling for Laser Bridge AK

Sunday, April 19, 2015: 9:11 AM
Room 1A (San Diego Convention Center)
Anita Nevyas-Wallace, MD
Harald P. Studer, PhD
Cynthia J. Roberts, PhD

To build and validate a patient-specific computational model of a novel astigmatic keratotomy (AK) incision architecture, the Laser Bridge AK.

Finite element modeling simulated the novel architecture of Laser Bridge AK in a custom mathematical function which considered corneal incompressibility and nonlinearity, fiber-induced anisotropy, and inhomogeneity.  A 76 year old man underwent phaco/IOL with AK o.s.  A DuoTrak blade was used to create a 9mm optical zone nasal AK 150 microns shallower centrally than at its ends.  Incision morphology was measured via Optical Coherence Tomography.  Pre-and post-op patient specific Galilei tomography were imported into Optimeyes software. The simulated incisions’ result was calculated with ABAQUS.  Post-operative results were compared to the simulated post-operative model for validation.

The patient’s astigmatism was reduced from 1.75D against the rule to 0.25D with the rule. The simulated outcome was compared with the postoperative Galilei corneal tomography. The simulated outcome showed a close match to the measured post-operative results.

Patient-Specific Finite Element Modeling of the Laser Bridge AK was validated for the patient modeled.  Future studies include comparing different novel incision architectures.