Baltimore Washington Eye Center, Maryland

Tuesday, December 6, 2011

Contact Lens-The EYE App Technology Advances

Advances in contact lens design have made lenses healthier, more comfortable and able to correct a wider array of vision problems. However, have you ever considered the other ways contact lenses can be used that have nothing to do with correcting vision?

For years contact lenses have been used to aid in the healing of corneal abrasions. Scratches on the surface of the eye will often heal on its own. However, every blink causes discomfort as the lid rubs over the abraded area. Additionally the mechanical force of the lid on the surface of the eye can make it more difficult for new cells to fill the area of the abrasion. Inserting a contact lens acts as a bandage protecting the delicate surface as it heals and improving patient comfort during the healing process.

Glaucoma is a complex disease whose etiology is a matter of debate. Although once thought to be the hallmark of glaucoma, elevated eye pressure is now known to be just one of the risk factors for this disease. As a matter of fact, some people with glaucoma never have a pressure outside of the normal range and some patients being treated for glaucoma with pressure lowering drops seem to progress in their disease despite having pressures measured in the office at adequate levels. The pressure reading done in the doctor’s office is merely a momentary snapshot of a dynamic pressure reading that likely fluctuates through the day and night. Sensimed, a Swiss company, has developed the Triggerfish electronic contact lens that can measure and record eye pressure readings for an entire day. This new information will likely prove invaluable for scientists as they strive to understand the true role of intraocular pressure in the diagnosis and management of glaucoma.

Delivering medications to the eye and having them absorbed effectively has always been a challenge. It has been estimated that "approximately 95% of the drug contained in the drops is lost due to absorption through the conjunctiva or through the tear drainage.”  Contact lenses impregnated with drugs have been used since the 1960s. However, the goal of continuous consistent sustained release of medication was difficult to achieve. Recent advances in contact lens materials and nano particle technology may make a commercially viable product a reality. An article reviewing the current state of these technologies notes that "The use of soft contact lenses for therapeutic drug delivery may correct three inherent deficiencies seen with the typical administration of eye drops into the eye: (i) the contact time of drug with the precorneal tear film may be longer; (ii) compliance as compared to frequent and complicated dosage regimens may be improved; and (iii) less systematic toxicity may be expected because of the total amount of drug administered compared to multidrops”.

Guest Blogger: Shari E. Strier, O.D., Optometrist with the Baltimore Washington Eye Center