Discovery of Lymph Channels in Eye May Help Glaucoma
Scientists have proved that there are wonders yet to be discovered in the human body. A Canadian research team has uncovered lymph channels in the eye, a find that could lead the way to improved treatments for glaucoma and possibly other eye diseases.
The lymphatic system consists of organs, ducts, and nodes that transport a watery clear fluid called lymph, which performs two major functions. The fluid distributes immune cells called lymphocytes and other elements throughout the body, which protect the body against infections. It also interacts with the blood to drain waste and fluids from cells and tissues. Lymphatics are found in every part of the body except the central nervous system and, until now, the eyes were excluded as well.
Glaucoma is a group of eye diseases that lead to damage of the optic nerve, which can then lead to vision loss and possibly blindness. Damage to the optic nerve usually occurs in the presence of elevated pressure in the eye due to fluid buildup, although it can occur with normal pressure. According to National Glaucoma Research, approximately 2.2 million people age 40 and older in the United States have glaucoma. It affects more than 66 million people around the world, and is a leading cause of irreversible blindness.
The Canadian research team challenged the long-held belief that the eye does not have any lymphatic circulation, which is separate from blood circulation, that could clear fluids from the eye. The scientists used molecular tools and three-dimensional reconstruction and identified lymphatic channels in the ciliary body (a blood-filled tissue layer behind the iris) of the eye. They confirmed their findings using electron microscopy. This discovery shows that the eye has a circulation system that plays a role in clearing fluids from the eye, which is critical in glaucoma.
“This discovery is exciting because it means we can focus on innovative treatment strategies for patients with glaucoma by specifically target this new circulation to lower eye pressure,” according to co-author Dr. Neeru Gupta, Director of the Glaucoma Unit and Nerve Protection Unit at St. Michael’s Hospital and Professor of Ophthalmology at University of Toronto, in a University news release. Future research will focus on understanding how to influence the lymphatic circulation in the eye to develop new ways to prevent glaucoma and blindness.
All of this could be good news for the tens of millions of people who have glaucoma. Currently the treatment for glaucoma includes use of eye drops or surgery to lower eye pressure either by reducing the formation of fluid or improving its drainage from the eye. Although the disease can affect anyone, those at greatest risk include the elderly, people with elevated eye pressure, and those who have a family history of the disease. Presence of diabetes, high blood pressure, and near-sightedness also may be risk factors.
Glaucoma Research Foundation
University of Toronto