Glaucoma treatment has always been painfully fiddly, but a new method that uses a contact lens to deliver medication slowly over a period of weeks may change all that.
Researchers from Massachusetts Harvard Medical School Department of Opthalmology, together with the Massachusetts Institute of Technology, have announced that they are now closer than ever before to developing a contact lens that delivers the common glaucoma treatment latanoprost.
For almost 50 years, researchers have wanted to utilize contact lenses to fight glaucoma, the world’s leading cause of irreversible blindness, and therein drastically improve the treatment of ocular degeneration. Now, they believe that the treatment may be in sight.
What is Glaucoma?
Glaucoma is a broad term that is used to describe a number of different diseases that affect vision and that worsen over time, often to the point where sufferers will go blind.
Glaucoma usually happens when the tubes that drain the eye get blocked. When fluid cannot drain from the eye, pressure begins to build. This pressure can damage the optic nerve which is the nerve that connects the eye to the brain. The nerve fibers can also be damaged.
In the case of the most common type of glaucoma (chronic open-angle) or what is known as secondary glaucoma (developing after an injury or another eye condition) this will cause a gradual loss of sight and can result in permanent blindness.
What are the Current Treatments for Glaucoma?
If diagnosed early, which is crucial for preventing irreversible blindness, Glaucoma is usually treated with eye drops. In other cases, laser treatment can be used, or even surgery. In most cases sight degeneration cannot be reversed and so glaucoma treatment is about preventing further loss of vision.
Why Aren’t Eye Drops Good Enough?
To be sure, eye drops can be effective in treating glaucoma and if you have been prescribed eye drops, they can and will work.
However, it is undeniable that eye drops are quite inefficient in how they deliver the required treatment. Furthermore, people can often forget to use their eye drops, especially because multiple applications may be required during an average day. As such, they are unlikely to keep to the strict regime that is needed to ensure that treatment is effective. Elderly people, who make up a significant number of glaucoma sufferers, may also struggle to use eye drops without assistance.
This is where the contact lens delivery method could change things.
How do the New Contact Lenses Differ?
The contact lens delivery method was created by putting latanoprost-polymer films in an everyday contact lens hydrogrel. The lens has a normal central area that will allow the lens to function as a vision corrector. Yet, at the edge of the lens there is what is known as a drug-polymer film which will slowly release the medication. The lenses have been tested and do not refract images. They can also be used for near or far-sighted eyes.
Crucially, the test lenses have been developed using materials that have already been approved by the FDA for use in the eye, dramatically reducing the timeframe by which we could see this product being used in everyday life.
“In general, eye drops are an inefficient method of drug delivery that has notoriously poor patient adherence. This contact lens design can potentially be used as a treatment for glaucoma and as a platform for other ocular drug delivery applications,” said lead researcher Joseph Ciolino, M.D, Massachusetts Eye and Ear cornea specialist.
The contact lens delivery method has already been tested in a variety of situations and has been shown to deliver levels of the glaucoma treatment that are at least comparable to using eye drops. The latest results show that the lens has the ability to continue to release the medication over long periods of days and weeks, and even a full month in some cases.
The researchers findings appear online and will be published in the January 2014 printed issue of Biomaterials.
Photo credit: Thinkstock.