CHESTNUT HILL, Mass., May 5, 2015 /PRNewswire-USNewswire/ -- A paper to be published in the British Journal of Ophthalmology by Perry Rosenthal, M.D. of the Boston EyePain Foundation and David Borsook, M.D., Ph.D. of Harvard Medical School describes a fundamentally new theory of the cause of the commonest form of dry eye disease and also identifies a previously unidentified suicide-provoking, eye-centered pain disease that the authors have named oculofacial pain.
The paper is accessible online (at http://bjo.bmj.com/content/early/recent; doi: 10.1136/bjophthalmol-2014-306280) and scheduled to be published later this year in a print issue of the peer-reviewed journal for health professionals and researchers in ophthalmology.
Commonly known as dry eye disease, this particular disorder impacts the lives of tens of millions of people in the U.S. alone and its huge cost to society has defined it as a major public health challenge that has attracted enormous research funds and brilliant scientists to find a cure or effective treatments.
"We suggest that the meager results of these efforts have been due to the misplaced focus on tears rather than the underlying cause, which we believe is malfunctioning nerves of the corneas' complex pain system," said Dr. Rosenthal. "The mystery has been that while dry eyes feel dry, many eyes that feel dry are not dry."
The conventional explanation is that although sufficient in amount, the tears of these "dry eyes" evaporate too quickly because the secretions produced by Meibomian glands in the eyelids – an oily film that covers the tear films to slow its evaporation – are inadequate and that diseases of these glands increase dry eye-like symptoms. On the other hand, a 2013 study found no relationship between the health of Meibomian glands and abnormal dry eye symptoms.
Drs. Rosenthal and Borsook present a new theory that they suggest accommodates these seemingly contradictory findings. The authors' note that unidentified diseases of the corneal nerves increase the sensitivity of their specialized tear thickness sensors causing these eyes to feel dry despite the presence of adequate tears. They explain these symptoms as "false dry eye alarms" and suggest that over time the progression of the corneal nerve disorder eventually degrades their ability to efficiently transmit the messages for more tears to the tear glands, eventually resulting in fewer tears.
"If validated," said Dr. Rosenthal, "this would emphasize that dysfunctional corneal nerves rather than tears being the underlying disease in the most common type of so-called dry eye disease as currently assumed. Treatments could then be focused on correcting the underlying nerve disease."
Moreover, their paper also describes for the first time another pain disorder, which the authors call oculofacial pain, characterized by eye-centered, high intensity, unrelenting pain that may include severe photosensitivity. Although perceived as originating in, around and/or behind the eyes and often the head, ears, face, jaws and even teeth, the authors believe that this disease represents a form of pain known as centralized pain that originates in certain pain-control centers in the brain and projects the symptoms to body parts they normally serve, in this case locations above the neck.
"This explains the absence of signs of their cause despite their severity," said Dr. Borsook. "The quality and patterns of this pain vary among patients and can include burning, sharp, cutting, aching, pressure, pins and needles and that mimicking severe dry eyes." Oculofacial pain is often triggered by corneal nerve damage (such as caused by LASIK surgery or even minor irritants), it can begin spontaneously, and is often associated with the disease fibromyalgia.
Because this pain syndrome has not been previously reported and its symptoms are not supported by objective finding, they are often believed by doctors to be imagined or exaggerated. The authors believe that the feeling of being abandoned by the medical profession nurtures patients' commonly reported intrusive thoughts – and may be so severe, sometimes dramatic actions including suicide.
"We hope that this paper will legitimize the extraordinary suffering that these patients endure, and encourage neuroscientists and pain researchers to recognize its validity, study this devastating and overlooked disease, and develop effective treatments," said Dr. Rosenthal.
About Dr. Rosenthal
Perry Rosenthal, M.D. is an ophthalmologist who, while training at the Harvard Medical School-affiliated Massachusetts Eye and Ear Infirmary, founded its Contact Lens Service and subsequently pioneered the development of rigid gas permeable contact lenses. He designed the first practical gas permeable scleral lens that rests entirely on the white tissue of the eye (sclera) and vaults the cornea, creating a space filled with oxygenated artificial tears. This "liquid corneal bandage" has restored sight and eased the eye pain of thousands of patients through the nonprofit Boston Foundation for Sight, an organization he founded. Rosenthal later established the Boston EyePain Foundation to continue his research into the causes of inadequately explained severe eye pain.
About Dr. Borsook
David Borsook, M.D., Ph.D. is Professor of Anesthesiology Harvard Medical School and the Director of the Pain and Imaging Neuroscience (P.A.I.N.) Group at Boston Children's, Massachusetts General and McLean hospitals. He has previously been the Director of the Pain Program at Massachusetts General Hospital and involved in numerous National and International Programs. He is a pioneer in the science of functional brain imaging of patients suffering from chronic pain. He has authored over 180 peer-reviewed publications and is the lead editor of three books.
About the Boston EyePain Foundation
The Boston EyePain Foundation, a 501(c)(3) non-profit organization, was created to expand the conversation on possible causes of inadequately explained chronic dry eye and other eye pain symptoms, and to support the establishment of a multidisciplinary Eye Pain Institute as a center for research for the development of new generations of treatments for neuropathic oculofacial pain. For more information, visit www.bostoneyepain.org.
SOURCE Boston EyePain Foundation