What type of lens can contribute to overlapping cells in the endothelium?

What type of lens can contribute to overlapping cells in the endothelium?

• A. Soft contact lenses
• B. Rigid gas permeable lenses
• C. PMMA contact lenses
• D. Orthokeratology lenses

Answer: (C)

The type of lens that can contribute to overlapping cells in the endothelium is PMMA contact lenses. These lenses are made from polymethyl methacrylate, which is a hard material that does not allow oxygen to pass through easily. When PMMA lenses are worn, the limited oxygen permeability can lead to hypoxia (a deficiency in the amount of oxygen reaching the tissues) in the corneal endothelium, which may result in cellular changes. Over time, this lack of sufficient oxygen can cause endothelial cells to become stressed and may lead them to overlap or change shape, potentially losing their regular arrangement. This cellular alteration can compromise the health of the cornea and may lead to various complications, including corneal edema. In contrast, soft contact lenses typically allow more oxygen to reach the cornea due to their greater water content and design, while rigid gas permeable lenses provide better oxygen transmission than PMMA. Orthokeratology lenses are designed to reshape the cornea temporarily and are also made from materials that allow better oxygen flow to the cornea. Such lenses, therefore, tend to maintain healthier endothelial cell patterns.

The type of lens that can contribute to overlapping cells in the endothelium is PMMA contact lenses. These lenses are made from polymethyl methacrylate, which is a hard material that does not allow oxygen to pass through easily.

When PMMA lenses are worn, the limited oxygen permeability can lead to hypoxia (a deficiency in the amount of oxygen reaching the tissues) in the corneal endothelium, which may result in cellular changes. Over time, this lack of sufficient oxygen can cause endothelial cells to become stressed and may lead them to overlap or change shape, potentially losing their regular arrangement. This cellular alteration can compromise the health of the cornea and may lead to various complications, including corneal edema.

In contrast, soft contact lenses typically allow more oxygen to reach the cornea due to their greater water content and design, while rigid gas permeable lenses provide better oxygen transmission than PMMA. Orthokeratology lenses are designed to reshape the cornea temporarily and are also made from materials that allow better oxygen flow to the cornea. Such lenses, therefore, tend to maintain healthier endothelial cell patterns.