Contact lenses release anesthesia to your eyeballs

For laser eye surgery patients, eye drops with pain medications could actually lead to drug overdose. New bandage contact lenses with vitamin E could help extend the release over days.
Written by Janet Fang, Contributor

The head tilts and forceful eyelid yanks that come with using eye drops is pretty annoying enough… but imagine having to do all that right repeatedly after eye surgery.

So scientists have developed contact lenses that would provide a continuous supply of anesthetic medication to the eyes of patients who undergo laser eye surgery.

More than 1 million laser eye correction procedures are performed a year in the US. While LASIK (laser-Assisted in situ keratomileusis) is the most common of these, complications can arise if the patient undergoes trauma or gets hit very hard afterwards.

On the other hand, PRK (photorefractive keratectomy) doesn’t have this complication, making it the preferred choice for athletes and those in the military. BUT this procedure comes with a longer period of pain after surgery.

PRK patients have to wear a special post-op ‘bandage contact lens’ to help the outer layer of the eye heal. And for the pain, they have to drop several medications into their eyes every few hours – which can actually increase the risk of drug overdose.

A team led by Anuj Chauhan from the University of Florida tested whether anesthetics loaded onto a bandage contact lens could release the drugs over time automatically.

They found that adding vitamin E to the lenses extended the time of release of 3 common anesthetics: from under 2 hours up to an entire day (even a few days in some instances).

The vitamin E acts as a barrier, keeping the anesthetics on the eye where they’re needed.

Late last year, I wrote about using contact lenses to deliver time-release doses of eye medication. Those promise to deliver a constant flow of drugs – such as anti-inflammatories, antibiotics and anti-allergy treatments – without altering the wearer’s vision.

The report appears in the American Chemical Society’s journal Langmuir.

Via American Chemical Society.

Image by Cobrakarin via Flickr

This post was originally published on Smartplanet.com

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