Which DK category is associated with a shorter lens life span?

Which DK category is associated with a shorter lens life span?

• A. Low-DK
• B. High-DK
• C. Hyper-DK
• D. Medium-DK

Answer: (C)

The main idea here is how the oxygen-permeability of a GP lens material affects not just corneal oxygen supply but also the lens’s durability in wear. Materials with extremely high oxygen permeability (Hyper-DK) achieve this by incorporating silicone-rich networks. That structure boosts oxygen flow, but it can also make the material more prone to issues like dehydration, surface changes, and interactions with cleaning solutions, which can shorten the lens’s practical life span. In other words, the trade-off for maximum oxygen delivery sometimes shows up as a shorter usable life of the lens. Lower to high-DK materials tend to be more chemically and mechanically durable, so they often last longer between replacements, even though they don’t provide as much oxygen.

The main idea here is how the oxygen-permeability of a GP lens material affects not just corneal oxygen supply but also the lens’s durability in wear. Materials with extremely high oxygen permeability (Hyper-DK) achieve this by incorporating silicone-rich networks. That structure boosts oxygen flow, but it can also make the material more prone to issues like dehydration, surface changes, and interactions with cleaning solutions, which can shorten the lens’s practical life span. In other words, the trade-off for maximum oxygen delivery sometimes shows up as a shorter usable life of the lens. Lower to high-DK materials tend to be more chemically and mechanically durable, so they often last longer between replacements, even though they don’t provide as much oxygen.