Glaucoma

WHAT is glaucoma?

Glaucoma is a potentially blinding disease that affects over 60 million people worldwide currently and is predicted to affect 120 million people by 2040. Vision loss from glaucoma results from damage that accumulates in the nerve that takes information from the eye to the brain – the optic nerve. This damage occurs at the optic nerve head, the point where the nerve tissue exits the eye. In patients with glaucoma, elevated pressure within the eye (intraocular pressure) can lead to changes that cause pinching of the optic nerve head. Over the course of many years, this pinching can cause irreversible nerve death and eventually vision loss. Currently, the only way that we have to treat this disease is by lowering intraocular pressure.

HOW can we protect the nerve head?

Like the bones in our body, the material that makes up the walls of our eyes – the sclera – is always rebuilding and remodeling itself. In glaucoma patients, this remodeling process leads to stress and pressure at the optic nerve head which gives rise to nerve damage and vision loss. We are currently identifying and testing drugs that prevent vision loss by changing the way the wall of the eye remodels in response to elevated intraocular pressure. Rho-kinase inhibitors (RKI) are a class of drugs already approved for use in the eye that we identified recently as having the capacity to inhibit remodeling. There are three directions we are taking this line of research. First, we are more clearly defining the mechanisms of RKI activity. We are also performing screens to identify new medications with the ideal balance of potent remodeling inhibition and few, if any, side effects. Lastly, we are developing novel ways to deliver these medications. This last step is pivotal towards moving these discoveries to the clinic and will benefit from our close collaboration with the Center for Nanomedicine at Wilmer.

IN WHAT way can we improve glaucoma surgeries?

For many glaucoma patients, surgery is the best option to obtain sustained intraocular pressure reduction and stop the progression of vision loss. Unfortunately, there are limitations to surgery. In some cases, the scar tissue seals the surgical site and prevents any further intraocular pressure reduction. Other patients may suffer from pressure that goes too low resulting in impaired vision. We have designed and fabricated tiny shunts that are created by spinning thin fibers (1000 times thinner than a human hair) around a template wire. Using this fabrication technique we can create shunts that are far more sophisticated than ones currently in clinical use. These shunts can be designed to release medication to maintain patency or to change diameter over time to avoid low eye pressures.

Researcher Highlights

Dr. Pitha’s Ph.D training is in pharmacology and toxicology – fields that focus on both identifying new drugs to treat diseases as well as developing more effective ways to deliver treatments. Glaucoma is a disease that needs help in each of these areas. We need to identify drugs that better protect the eye from glaucoma damage but perhaps more importantly, we need better treatment strategies than tedious daily eye drops, injections into the eye, or the currently available surgeries.