UNASSIGNED: Given various types of contact lens plungers available on the market, no study has yet been done on mechanical effects of the contact lens plunger on contact lens removal. Here, this study used finite element analysis to investigate the effects of plunger size and plunger position on the removal of soft and rigid gas permeable (RGP) contact lenses.
UNASSIGNED: First, we established finite element analysis models for the plunger, contact lens, cornea, and aqueous humor. The plunger is made of mostly silicone rubber, and the contact lenses are mainly made of soft and hard material. The part of the plunger used for removal was located either at the central or the edged position, with pulling 1 mm distance. The main parameters observation indicators of in this study were the reaction force at the fixed end of the cornea, aqueous humor, the von Mises stress of the plunger, the contact lenses, and the cornea.
UNASSIGNED: Results of this study showed that when a plunger of a larger diameter was used, the reaction force of the plunger was also larger, especially when applied to RGP lenses, which required a slightly larger force (∼0.27 N). Also, when removing a RGP lens from the edge, there was a greater stress at the edge of the contact lens (2.5799 MPa), and this caused a higher stress on both the cornea (0.0165 MPa) and the aqueous humor (0.00114 MPa).
UNASSIGNED: When using a plunger with a larger diameter to remove a RGP lens, although a larger force required, the relatively larger contact area likely reduced the stress on the cornea and aqueous humor, thereby reducing the risk of eye injury. In addition, when removing a RGP lens, the results of this study recommended it to be removed from the plunger edge, as that facilitated the removal of contact lens.
■鉴于市场上有各种类型的隐形眼镜柱塞,目前还没有关于隐形眼镜柱塞对隐形眼镜摘除的机械影响的研究。这里,这项研究使用有限元分析来研究柱塞尺寸和柱塞位置对移除软性和刚性透气性(RGP)隐形眼镜的影响。
■首先,建立了柱塞的有限元分析模型,隐形眼镜,角膜,和房水。柱塞主要由硅橡胶制成,隐形眼镜主要由软硬材料制成。用于拆卸的柱塞部分位于中心位置或边缘位置,拉1毫米的距离。本研究的主要参数观察指标为角膜固定端的反作用力,房水,柱塞的vonMises应力,隐形眼镜,还有角膜.
■这项研究的结果表明,当使用较大直径的柱塞时,柱塞的反作用力也更大,特别是当应用于RGP镜头时,这需要一个稍大的力(~0.27N)。此外,从边缘卸下RGP镜头时,隐形眼镜边缘有更大的应力(2.5799MPa),这对角膜(0.0165MPa)和房水(0.00114MPa)造成了更高的压力。
■当使用较大直径的柱塞卸下RGP透镜时,虽然需要更大的力量,相对较大的接触面积可能会减少对角膜和房水的压力,从而降低眼睛受伤的风险。此外,移除RGP镜头时,这项研究的结果建议将其从柱塞边缘移除,因为这有利于隐形眼镜的摘除。