Defeating dry eye disease

The importance of treating dry eye disease was the subject of “Advances in dry eye: disease perspectives, treatment options, and post-surgical management,” a symposium held in conjunction with the World Ophthalmology Congress (WOC).

Dry eye is believed to be one of the most commonly diagnosed ocular conditions, yet, few studies have provided good data on the magnitude of the problem, according to Donald Tan, MBBS, FRCSE, FRCSG, FRCOphth, FAMS, professor and head, Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, and director, Singapore National Eye Centre.

“We do know that tear deficiency is not the whole story,” Dr Tan said. Healthy tears, he said, are a complex mixture of proteins, mucin, and electrolytes. Compared with healthy tears, tears of patients who suffer from chronic dry eye have fewer proteins, decreased growth factor concentrations, altered cytokine balance, a lower level of soluble mucin 5AC, increased electrolytes, and activated proteases.

Fortunately, a continuum of care is available to treat dry eye across four severity levels, ranging from mild to severe.

According to Steven Wilson, MD, director of corneal research, Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, US, treatment options vary depending on the level of severity of the disease. These options range from patient education and environmental modification for the mildest level 1 disease, through to a wide rage of lubricating eye drops and ophthalmic cyclospine for level 2, to oral tetracycline and punctal plugs (if inflammation is controlled first) for level 3, up to systemic anti-inflammatory therapy, oral cyclosporine, and punctual cautery surgery for the most severe level 4 disease.

“Left untreated, dry eye may become a progressive disorder," Dr Wilson said. "Patients suffering from dry eye disease may move between severity levels and can become worse if untreated.”

He added that dry eye consensus guidelines developed by a panel of experts convened at the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, US, are easy to use and can prompt earlier treatment of dry eye disease.

“We conducted a non-randomized, multicentre study in which nine physicians enrolled 183 patients with dry eye disease over a three-month period,” Dr Wilson said. “Physicians in the study found the treatment algorithm easy to implement in clinical practice, and use of the guidelines highlighted the potential for disease progression and prompted treatment at earlier stages.”

Early treatment is essential, added Eric Donnenfeld, MD, FACS, Ophthalmic Consultants of Long Island and professor of ophthalmology, New York University Medical Center, US.

“The tear film is the most important refracting surface of the eye,” Dr Donnenfeld said. “Vision starts with the ocular surface.”

Controlling dry eye is particularly important when it comes to surgical patients, as dry eye can affect surgical outcomes, according to Dr Donnenfeld.

”Pre-existing, uncontrolled dry eye is a contraindication for elective eye surgery, and dry eye is the most prevalent nonsurgical complication of eye surgery,” Dr Donnenfeld said.

Dry eye is the most common postoperative complication of LASIK, affecting more than half patients during the first six months postoperatively - many of whom have dry eye problems for six to 12 months afterwards, he added. Dry eye also is common following refractive procedures such as IOL implantation.

“When postoperative patients complain about fluctuations in vision with blinking, always think of the ocular surface as being the problem,” Dr Donnenfeld said.

Preoperative measures are important to maintain a healthy tear film and optimize surgical outcomes, Dr Donnenfeld said. He recommended treating patients with signs or symptoms of dry eye prior to surgery to restore the tear film and maintain ocular surface health. In addition, preoperative use of cyclosporine can improve visual results in LASIK and IOL implantation.