Contact Lens Exams
Contact Lens Complications
Patients often ask why they need a yearly eye exam to update their contact lens prescription. The main reason is to ensure the contact lens is not causing any damage to the eye (Watch how poor contact lens hygiene is causing one woman to go blind in this video). Contact lenses can cause mechanical damage, induce bacterial infection, or cause poor oxygen transmission to the front part of the eye. These conditions can be ongoing without causing any discomfort or decrease in vision. We often see patients for routine eye exams, only to find that their contact lenses have been causing damage without their knowledge.
Common Contact Lens Disorders:
- This is an extremely common result of contact lens wear. It is caused by inadequate oxygen transmission to the front part of the eye. The cornea gets its oxygen from the environment and when you wear a contact lens you decrease the amount of oxygen that can get to the cornea. When that happens for an extended period of time, the cornea starts to send out signals calling for more oxygen. The body responds to the signals by building new blood vessels to transport oxygen to the areas of need. This would be great except for the fact the cornea is an avascular tissue, designed to transmit light. In addition, the abnormal blood vessels can be leaky and can cause more damage to the eye. Appropriate interventions include not sleeping with your contact lenses in, changing cleaning solutions, or changing your contact lens modality
Giant Papillary Conjunctivitis
- This condition is a result of allergic complications with contact lens wear. Allergens and other irritants can stick to the surface of your contact lenses. With each blink the underside of the eyelid interacts with the allergens adhered to the lenses, leading to inflammation and resulting in uncomfortable contact lens wear. With this condition it is important that you and your doctor discuss potential interventions. Including the use of anti-allergy drops, lubricating eye drops, different contact lens cleaning regimens, or switching your contact lens modality entirely.
- This condition is thought to have a few different causes. The one we will focus on is based on the idea of bacterial hypersensitivity. Infiltrative keratitis is caused by an inflammatory reaction to bacteria on the contact lens. The bacteria are generally not present in high enough numbers to cause a full blown infection, but there are enough to cause the body to send mediators to fend off the bacterial insult. In this case the inflammatory mediators produced by the body cause the damage to your eye, not the bacteria themselves. Interventions may include combination steroid/antibiotic eye drops, more advanced contact lens cleaning systems, or switching your contact lens modality completely.
- Microbial keratitis is inflammation of the cornea secondary to bacterial infection. In this situation bacteria are present in high enough quantities to cause infection, and can be serious enough to perforate the front part of the eye and can cause permanent vision loss. This condition is very serious and warrants immediate attention by an Eye Doctor. Interventions include anti-microbial eye drops, anti-microbial ointments, and possibly steroid eye drops after the infection is under control. Once the infection is under control it may be necessary to change contact lens cleaning systems, or switch contact lens modalities completely.