Tm激光与角膜作用的热效应模拟

激光角膜热成形技术(LTK)在矫正远视临床中占有重要的应用前景。为了了解铥激光与角膜组织热相互作用中激光参数和角膜光学及热物性参数对温度场分布的影响,选取50W/cm2,55W/cm2,60W/cm2三种功率密度,1s、2s、3s三种作用时间,用有限元方法模拟了激光作用下角膜组织内温度场的分布。模拟结果表明激光有效穿透深度与激光功率密度和时间都是正向相关,而与能量密度的正向相关性较差;激光作用时间越长,角膜组织中的温度梯度越小。模拟得到激光功率密度50W/cm2作用时间1s适合于LTK。

Simulation of thermal effects for interaction of Tm laser with cornea

LTK(laser thermal keratoplasty) will has a important application future for correction of hyperopia.The temperature distribution in cornea which radiated by Tm laser with power density 50W/cm2,55W/cm2 and 60W/cm2 and treatment time ls,2s and 3s respectively was simulated by finite element method,in order to understanding influence of temperature distribution on laser,optical and thermal parameters of cornea.The results indicated that laser effective penetrating depth and laser power density and radiating time is positive relationship,but the relationship with energy density is not good.When laser treatment has longer time, temperature grads in the cornea have smaller.The result of simulation obtained that both laser power density 50W/cm2 and treatment time ls was fitted for LTK.