Contact Lens - Complications

Complications

Complications due to contact lens wear affect roughly 5% of contact lens wearers each year. Most complications arise when lenses are worn differently than prescribed (improper wear schedule or lens replacement) Sleeping in lenses not designed or approved for extended wear is a common cause of complications. Many people go too long before replacing their lenses, wearing lenses designed for 1, 14, or 30 days of wear for multiple months or years. While this does save on the cost of lenses, it risks permanent damage to the eye and loss of sight.

The way contact lenses interact with the natural tear layer is a major factor in determining lens comfort and visual clarity. People that suffer from dry eyes are particularly vulnerable to mild discomfort and episodes of brief blurry vision.

Improper use of contact lenses may affect the eyelid, the conjunctiva, and the various layers of the cornea. Poor lens care can lead to infections by various microorganisms including bacteria, fungi, and Acanthamoeba. Long-term (over 5 years) use of contact lenses may "decrease the entire corneal thickness and increase the corneal curvature and surface irregularity." Long-term wear of rigid contact lens is associated with decreased corneal keratocyte density and increased number of epithelial Langerhans cells.

All contact lenses sold in the United States are studied and approved as safe by the FDA when specific wear schedules and replacement schedules are followed.