Contact Lenses

A contact lens, also known as a contact, is a corrective, cosmetic or therapeutic lens which is normally placed on the cornea of the eye. Contact lenses normally serve the same purpose as eyeglasses, that is, to correct the vision. However, contact lenses are normally virtually invisible and extremely lightweight. Most contact lenses are tinted a light blue when merged in storage and cleaning solutions. Some contact lenses are tinted to intentionally change the appearance of eye color. These lenses are cosmetic in nature but can also be corrective. Individuals often prefer to wear contact lenses over eyeglasses for several reasons, the most notable, being appearance and practicality. Comparatively to eyeglasses, contact lenses are less likely to get wet, do not steam up and provide a much wider field of vision making them much more practical for many patients. Additionally, ophthalmological conditions such as keratoconus and aniseikonia may not be accurately corrected with eyeglasses. Corrective contact lenses are designed to specifically correct vision. In many patients, there is a discrepancy between the refractive power of the eye and the length of the eye resulting in a refraction error. This error is a glitch in the focusing of light by the eye and a commonplace reason for poor visual acuity. A contact lens can balance this discrepancy by allowing correct focusing of light into the retina. Corrective lenses address conditions such as nearsightedness (myopia), farsightedness (hypermetropia), astigmatism and presbyopia. Contact lenses can only be worn for a short period of time. Usually patients must remove the lenses every night or every few days. There has been renewed interest in orthokeratology, the correction of myopia by deliberate overnight flattening of the cornea, leaving the eye without contact lens or eyeglasses correction during the day.

Cosmetic contact lenses are developed to intentionally change the appearance of the eye. The lenses can also be designed for the purpose of correcting vision as well. The FDA refers to non-corrective, cosmetic contact lenses as “decorative lenses”. Scleral lenses cover the white part of the eye (i.e. sclera) and are used in many cosmetic theatrical lenses. Theatrical lenses are mostly used in the entertainment industry to alter the appearance of the eye. Due to their size, these contact lenses can be difficult to insert and do not move very well within the eye. There can be some disturbance in vision with these lenses and it is advised that these lenses not be worn too much, however, research has shown them to have no direct link to any long term conditions of eye degradation. Similar lenses have more direct medical use. For example, some lenses can give the iris an enlarged appearance, or mask defects such as absence of (aniridia) or damage to (dyscoria) the iris.

Therapeutic contact lenses are normally soft and often used in the treatment and management of non-refractive disorders of the eye. A therapeutic contact lens protects an injured or diseased cornea from rubbing which allows for proper healing They are used in the treatment of conditions including bullous keratopathy, dry eyes, corneal ulcers and erosion, keratitis, corneal edema, descemetocele, corneal ectasis, Mooren’s ulcer, anterior corneal dystrophy, and neurotrophic keratoconjunctivitis.

A daily (disposable) wear contact lens, is designed to be removed daily normally before going to sleep. An extended wear contact lens is designed for continuous wear including throughout the night and normally can be worn for 7 consecutive days/nights depending on the brand. Newly developed materials, such as silicone hydrogels, allow for even longer wear periods of up to 30 consecutive days/nights. These longer-term lenses are often referred to as continuous wear. Extended lens wearers may have an increased risk for corneal infections and corneal ulcers, primarily due to poor care and cleaning of the lenses, tear film instability, and bacterial stagnation. If you wear a contact too long an ulcer may occur.

Some brands of contact lenses include Vistakon/Johnson & Johnson, CIBA Vision, Bausch & Lomb and CooperVision, Conóptica, Conta Optic, Daysoft, Menicon and UltraVision. However, there are many more brands on the market and it is imperative to consult with either an Optometric Phyisician or Optometrist to find the best solution for your needs. An examination or consultation will deterimine your needs in conjuction with the current condition of your eye health.

For additional information or to schedule an Eye Examination, please contact us at (866) 611-7556.

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