Drug-releasing Contact Lenses

While there is no cure for glaucoma, medication can slow or prevent further vision loss. Glaucoma patients typically instill eyedrops on a daily basis to control the disease. However, only a minimal amount of the dose is actually absorbed by the eye. The rest either runs down the sides of the patient's face, is washed away by reflex tearing or dispersed by blinking.

Researchers are excited about new drug-releasing contact lenses that ensure glaucoma patients and others get correct and consistent dosages of medication. This could be a significant improvement on the traditional eyedrops that ophthalmologists prescribe for these patients, from which the eye absorbs as little as 1% of the dose. The contact lenses are capable of delivering the proper dosage and increasing the effectiveness of treatment.

What is Glucoma ?

Glaucoma refers to a group of diseases that affect the optic nerve and involves a loss of retinal ganglion cells in a characteristic pattern. It is a type of optic neuropathy. Raised intraocular pressure is a significant risk factor for developing glaucoma (above 22 mmHg or 2.9 kPa). One person may develop nerve damage at a relatively low pressure, while another person may have high eye pressure for years and yet never develop damage. Untreated glaucoma leads to permanent damage of the optic nerve and resultant visual field loss, which can progress to blindness.

Glaucoma can be divided roughly into two main categories, "open angle" and "closed angle" glaucoma. Angle closure can appear suddenly and is often painful. Visual loss can progress quickly but the discomfort often leads patients to seek medical attention before permanent damage occurs. Open angle, chronic glaucoma tends to progress more slowly and the patient may not notice that they have lost vision until the disease has progressed significantly.

Glaucoma has been nicknamed the "sneak thief of sight" because the loss of vision normally occurs gradually over a long period of time and is often only recognized when the disease is quite advanced. Once lost, this damaged visual field can never be recovered. Worldwide, it is the second leading cause of blindness. Glaucoma affects one in two hundred people aged fifty and younger, and one in ten over the age of eighty. If the condition is detected early enough it is possible to arrest the development or slow the progression with medical and surgical means.

Source : vision.about.com

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