Issue 502 – Differences between Regular and Therapeutic Contact Lenses and Key Considerations

Are you part of the myopic population? Have you ever worn contact lenses? Did you know that most contact lenses available at optical stores are classified as high-risk "medical devices"? What risks are associated with them, and how does this relate to their purchase and use? This article compares "regular" and "therapeutic" contact lenses to uncover the lesser-known aspects of contact lens use.

Regular Contact Lenses

In Taiwan, "regular contact lenses" are defined as those not intended for medical treatment or diagnosis, and they are what you typically buy in optical stores. Regular lenses are categorized based on material into soft and hard lenses.

Soft Contact Lenses

These are the most popular type. Made from flexible materials like hydrogel or silicone hydrogel, soft lenses adapt well to the curvature of the cornea, offering comfort and a short adaptation period. However, they are more prone to damage and may need to be replaced sooner.

Hard Contact Lenses

Previously dominant in the market, hard lenses were made from materials like PMMA but were less comfortable. Today, they are made from more advanced materials such as fluorosilicone acrylates, which reduce infection risks and maintain eye moisture. However, they may require an adaptation period and may not fit as comfortably as soft lenses.

Therapeutic Contact Lenses

Therapeutic lenses, also known as non-regular lenses, are designed for medical use and require a prescription from an ophthalmologist. In Taiwan, these are commonly used to manage myopia in children, including orthokeratology lenses and myopia control lenses.

Orthokeratology Lenses

These rigid lenses are worn overnight to reshape the cornea temporarily, correcting myopia without surgery. They are generally safe for children and adolescents but require careful cleaning and maintenance to prevent infection risks such as keratitis and corneal ulcers.

Myopia Control Lenses

These are soft lenses worn during the day and replaced daily. They use special optical designs to slow the progression of myopia. They are easy to adapt to and have a lower risk of infection, though they may cause dryness or oxygen deprivation to the cornea if worn too long.

Key Considerations for All Contact Lens Users

Regardless of the type, contact lenses must be used according to the instructions, including proper wear time and replacement schedules. Misuse, like wearing daily lenses for a month, can lead to lens damage and infection risks.

Proper cleaning is essential for eye health, as contact lenses can accumulate various substances such as proteins, lipids, dust, microorganisms, and residues from cooking or cosmetics. These can cause eye injuries or infections if not properly cleaned.

Since contact lenses are worn directly on the cornea, there are inherent risks. Defective lenses can lead to serious eye conditions, such as keratitis, corneal ulcers, and even blindness. Always purchase lenses approved by health authorities and have regular check-ups with an ophthalmologist to maintain optimal eye health.

Source: Food and Drug Administration Articles Network - https://reurl.cc/WNOM17