What is a significant characteristic of Extended Wear (EW) lenses?

Extended Wear (EW) lenses are specifically designed to be worn continuously for an extended period, often up to one week, without needing to be removed for sleep. This characteristic allows for convenience and flexibility for the wearer, who can maintain their vision correction without the daily routine of lens removal and cleaning. The materials used in EW lenses are often made to be more breathable, enabling adequate oxygen flow to the cornea, which is essential for eye health during prolonged wear.

Options suggesting that these lenses need to be removed every night or must be replaced weekly do not accurately describe EW lenses since their design purposefully supports extended continuous wear. Additionally, the belief that EW lenses are not suitable for astigmatism is incorrect, as there are options available for individuals with astigmatism that also fall under the category of Extended Wear lenses. Thus, the characteristic of being able to be worn continuously for up to one week is a defining feature of Extended Wear lenses.