July 24, 2012
Microneedles May Aid In Eye-Related Illnesses
Connie K. Ho for redOrbit.com — Your Universe Online
Needles are used by acupuncturists for therapeutic purposes, and new research shows that a specially developed needle can help treat illnesses related to the eye. The microneedles could be used to treat diseases like macular degeneration that hurts tissues in the back of the eyes. The research will be especially beneficial for the elderly population who have an eye-related disease as pharmaceutical companies who are working on creating new drugs that would otherwise have to be administered with an injection via hypodermic needle.
The findings were recently published in the journal Investigative Ophthalmology & Visual Science. The study was conducted by researchers from the Georgia Institute of Technology and Emory University. The needle is less than a millimeter in length and can bring easy delivery of drug molecules and particles to the eye. The injection also allows an easy passageway from the white part (sclera) of the eye to the eye´s inner surface and then to the back of the eye. Scientists believe that the new technique is minimally-invasive and is better than conventional methods that focus on drug injections to the center of the eye or eye drops.
"This research could lead to a simple and safe procedure that offers doctors a better way to target drugs to specific locations in the eye," explained first author Samirkumar Patel, postdoctoral researcher at Georgia Tech during the project, in a prepared statement. "The design and simplicity of the microneedle device may make it more likely to be used in the clinic as a way to administer drug formulations into the suprachoroidal space that surrounds the eye."
The results also demonstrate how the suprachoroidal space, located between the sclera and the choroid, could allow for the development of drugs and microparticles, reducing the use of frequent injections that target chronic eye diseases. Fluids that are normally injected into the suprachoroidal space move circumferentially around the eye, but the new study demonstrates that injections of fluids that have molecules and particles in that space can reach the targeted structures and stay there for longer periods of time. As well, other drug treatments have side effects such as impacting the lens or the front of the eye but the new needle injections wouldn´t have the same side effects.
"The study showed that if we inject non-degradable particles into the suprachoroidal space and wait as long as two months, the particles remain," commented Mark Prausnitz, a Regents professor in Georgia Tech's School of Chemical and Biomolecular Engineering, in the statement. "That means there is no natural mechanism to remove the particles from the eye. Knowing this, we can design biodegradable particles with drugs encapsulated in them that can slowly release those drugs over a period of time that we could control."
Furthermore, the new microneedles would have fewer traumas to the eye than hypodermic needles and decrease infection. Pharmaceutical companies are currently working to develop new compounds to treat eye disease that can be delivered to the part of the eye that needs treatment. The next step in the study would be to look how efficient the microneedle technique is moving real drugs to the necessary eye structures.
"With this technique, we are keeping the drug right where it needs to be for most therapies of interest in the back of the eye," mentioned Henry Edelhauser, a professor of ophthalmology at Emory School of Medicine, in the statement.