J Refract Surg. 2022 Sep;38(9):610-616. doi: 10.3928/1081597X-20220715-03. Epub 2022 Sep 1.
To evaluate the effect of simulated repetitive eye rubbing on the corneal biomechanics of porcine eyes using an ex vivo model system.
The average rubbing force that patients with keratoconus apply to their eyelids was previously determined. Fresh porcine eyes with eyelids were either exposed to 10,500 rub cycles from a custom-built eye rubbing machine that rubbed with a similar force to knuckle human eye rubbing (n = 33) or no rubbing at all (control; n = 37). A total of 10,500 rubs are equivalent to 1 year of rubbing six times daily, five movements per rub. The corneal biomechanical properties of these eyes were then tested by measuring the elastic modulus of 5-mm strips.
The elastic modulus at the range of 1% and 5% of strain was 1.219 ± 0.284 and 1.218 ± 0.304 N/mm in the eye rubbing group and the no-rub control group, respectively. Corneal stiffness was similar in both groups ( = .984).
The threshold to induce biomechanical changes (purely by eye rubbing) must be higher than 10,500 rubbing movements, suggesting that occasional eye rubbing may not affect corneal biomechanics in normal eyes, and likely only triggers keratoconus progression in predisposed corneas. Further in vivo studies assessing the impact eye rubbing has on inflammatory activity and the biomechanical properties of weakened corneas is warranted. .
使用离体模型系统评估模拟重复眼揉对猪眼角膜生物力学的影响。
先前已确定了圆锥角膜患者施加于眼睑的平均揉擦力。使用类似于指节揉擦人眼的力，来自建的眼揉擦机对新鲜带眼睑的猪眼进行 10500 次揉擦循环（n = 33）或根本不揉擦（对照；n = 37）。总共 10500 次揉擦相当于每天揉擦 6 次，每次揉擦 5 次，持续 1 年。然后通过测量 5mm 条带的弹性模量来测试这些眼的角膜生物力学特性。
在 1%和 5%应变范围内，眼揉擦组的弹性模量分别为 1.219 ± 0.284 和 1.218 ± 0.304 N/mm，无揉擦对照组分别为 1.219 ± 0.284 和 1.218 ± 0.304 N/mm。两组的角膜硬度相似（=.984）。
引起生物力学变化（仅通过眼揉擦）的阈值必须高于 10500 次揉擦运动，这表明偶尔的眼揉擦可能不会影响正常眼的角膜生物力学，并且可能仅在易患角膜引发圆锥角膜进展。进一步的体内研究评估眼揉擦对炎症活动和脆弱角膜生物力学特性的影响是必要的。
