人类角膜热粘弹性行为建模使用标准线性固体模型
Hassan M Ahmed1, Nancy M Salem2, Walid Al-Atabany2,3
1Biomedical Engineering Department, Helwan University, Helwan, Egypt. hassan.gbr@h-eng.helwan.edu.eg.
BMC ophthalmology
|June 5, 2023
概括
数学建模准确地模拟了人类角膜粘性弹性和热行为. 标准线性固体模型在预测角膜对负荷的反应方面优越,在FDA的热极限内确保安全.
科学领域:
- 眼科医生 眼科 眼科
- 生物医学工程 生物医学工程
- 计算力学 计算力学 计算力学
背景情况:
- 角膜生物力学对于了解角膜疾病和折射手术结果至关重要.
- 对角膜生物力学的体内和体外研究面临重大局限性.
- 数学建模提供了一种可行的解决方案,用于在现实的条件下研究体内角膜粘性弹性.
研究的目的:
- 使用数学模型模拟角膜粘性弹性和热行为.
- 评估凯尔文-沃伊格特和标准线性固体模型对角膜粘性弹性的有效性.
- 为了评估模拟负载期间角膜组织的温度升高.
主要方法:
- 采用了三个数学模型:凯尔文-沃伊特,标准线性固体 (SLS) 和生物热传递模型.
- 在恒定和短暂负载条件下模拟了粘性弹性.
- 使用SLS模型分析热行为,以计算温度上升.
主要成果:
- 标准线性固体模型在两种负载条件下都在模拟人类角膜粘弹性行为方面表现出卓越的准确性.
- 从SLS模型获得的变形幅度与临床发现相比,与凯尔文-沃伊格特更好地一致.
- 计算的角膜温度升高约为0.2°C,符合FDA的安全规定.
结论:
- 标准线性固体模型更有效地描述了人类角膜对恒定和短暂负荷的反应.
- 模拟的温度上升~0.2°C是很好的FDA软组织的安全限制.
- 数学建模,特别是SLS模型,为角膜生物机械分析提供了一种安全而准确的方法.
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