Yan Zhang, Junyu Lin, Shu-Hao Lu, Jones Iok-Tong Chong, Cheng Yang, Jianqing Lan, Wenjuan Xie, Juan Li, David Chuen-Chun Lam, Dan Cao, Jin Zeng
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引用次数: 0
Abstract
Background: Corneal refractive laser surgery is widely used to correct myopia and astigmatism due to its safety and effectiveness. However, postoperative changes in corneal biomechanics, such as corneal ectasia, can occur, necessitating a deeper understanding of these changes. Finite Element Analysis has shown promise in predicting surgical outcomes based on corneal biomechanics. Devices like the Ocular Response Analyser (ORA) and Corvis ST provide noninvasive ways to measure corneal biomechanics, aiding in the assessment of corneal behavior post-surgery. Young's modulus and tangent modulus are crucial parameters for describing corneal elasticity, but there is limited data on the changes in tangent modulus following Femtosecond Laser-Assisted LASIK (FS-LASIK) in humans. This study aimed to investigate the effect of FS-LASIK on the corneal tangent modulus using a novel corneal indentation device (CID). The study sought to explore changes in corneal tangent modulus after FS-LASIK, taking into account central corneal thickness (CCT) and corneal radius, to enhance our understanding of the biomechanical changes induced by this surgical procedure.
Results: Sixty-six patients (66 eyes) underwent FS-LASIK, resulting in significant changes in CCT, corneal radius, and Goldmann intraocular pressure (GAT IOP) 6 months post-surgery (△CCT = - 88 ± 31 µm, △corneal radius = 0.81 ± 0.30 mm, △GAT IOP = - 3.2 ± 2.4 mmHg, p < 0.001) 6 months after surgery. However, corneal stiffness did not significantly change (△ = - 0.002 ± 0.011, p < 0.2). The corneal tangent modulus showed a significant increase post-surgery (△ = 0.263 ± 0.146, p < 0.001), exhibiting a negative correlation with CCT (r = - 0.68, P < 0.001) and a positive correlation with corneal radius (r = 0.71, P < 0.001). For each 1 mm increase in corneal radius, there was a 0.23 MPa increase in corneal modulus, and for every 100 µm reduction in corneal thickness, there was a 0.14 MPa increase in corneal modulus.
Conclusions: The corneal tangent modulus, influenced by corneal radius and CCT, increased significantly following FS-LASIK. This study highlights the biomechanical changes induced by FS-LASIK, with implications for understanding corneal behavior post-surgery and its potential impact on patient outcomes.
期刊介绍:
BioMedical Engineering OnLine is an open access, peer-reviewed journal that is dedicated to publishing research in all areas of biomedical engineering.
BioMedical Engineering OnLine is aimed at readers and authors throughout the world, with an interest in using tools of the physical and data sciences and techniques in engineering to understand and solve problems in the biological and medical sciences. Topical areas include, but are not limited to:
Bioinformatics-
Bioinstrumentation-
Biomechanics-
Biomedical Devices & Instrumentation-
Biomedical Signal Processing-
Healthcare Information Systems-
Human Dynamics-
Neural Engineering-
Rehabilitation Engineering-
Biomaterials-
Biomedical Imaging & Image Processing-
BioMEMS and On-Chip Devices-
Bio-Micro/Nano Technologies-
Biomolecular Engineering-
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Cellular Engineering-
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Drug Delivery Technologies-
Modeling Methodologies-
Nanomaterials and Nanotechnology in Biomedicine-
Respiratory Systems Engineering-
Robotics in Medicine-
Systems and Synthetic Biology-
Systems Biology-
Telemedicine/Smartphone Applications in Medicine-
Therapeutic Systems, Devices and Technologies-
Tissue Engineering