Computer Simulation of Arcuate and Radial Incisions Involving the Corneoscleral Limbus

We have created a computer model of the eye that improves upon previous models with two assumptions: (1) the cornea is considered anisotropic, and (2) the strain tensor is non-linear for large displacements. Values used include those for Young’s modulus, Poisson’s ratio, and three coefficients of anisotropia. A finite element computer program was used to stimulate the behaviour of the eye. Four simulations were done:(1) a full thickness arcuate limbal cataract incision,(2) a partial thickness arcuate corneal relaxing incision,(3) a partial thickness radial incision extending across the limbus,(4) a partial thickness radial incision confined to the cornea.A full thickness corneal arcuate incision for cataract induced more change in corneal shape than a limbal incision. However, the gaping is more important in the limbal incision. Partial thickness arcuate corneal relaxing incisions were found to be more effective with a clear zone 3–5 mm in diameter.Radial incision simulation demonstrated little enhancement of the effect of the incisions when across the limbus. © 1989, College of Ophthalmologists. All right reserved.