The nuisance and misery of dry eyes

THE tear film is a layer on the eye surface which maintains the smoothness of the surface for good vision and comfort. It is made up of three layers: mucin, water and lipid. A disturbance in the balance of all three components may lead to symptomatic dry eyes.

Dry eye disease is a common pathology affecting more than 20% of the population, with symptoms increasing with age. Conditions of a modern lifestyle, including working on computer screens, driving, artificial lights, air pollution and wearing contact lenses makes dry eye syndrome a frequent nuisance.

Generally speaking, it is a result of tear film issue, either caused by insufficient tears or excessive evaporation. It is recognised that a large majority of cases are caused by the evaporation form, mainly due to an insufficiency of the external lipid layer of the tear film secreted by glands in the eyelids called the Meibomian glands.

Dry eye disease is an unpleasant sensory and emotional experience for patients. Burdened with discomfort and fear, patients often feel miserable, not knowing how to precisely describe what they are feeling. Most will end up feeling exasperated because no one understands what they are going through. Mild conditions can lead to frequent visits to eye care practitioners, while moderate to severe cases are often associated with significant pain, limitations in performing daily activities, reduced vitality, poor general health and, in some cases, depression.

The treatment is particularly frustrating to patient and practitioner, as it often interferes with the overall management and perceived satisfaction of the patient. There are significant symptoms, which are either not treated effectively or ignored by the eye care practitioner. Usually, this happens when there is not much time or it is perceived that the complaint is insignificant or untreatable.

Although lubricating eyedrops may provide some relief, it is often not enough in more severe conditions. Depending on the cause of the dry eyes, treatment will include eye drops such as cyclosporine, steroid eyedrops and lipid-based drops. Manual expression, Meibomian gland probing and a procedure called Blephex may also need to be done.

The latest addition to this armamentarium of treatment modalities is Intense Pulsed Light (IPL) therapy. It involves applying perfectly calibrated, homogenously sequenced, sculpted light pulses. The energy, spectrum and time period are precisely set to stimulate the Meibomian glands to cause them to return to their normal function.

Each treatment session takes only a few minutes, during which the patient is seated comfortably. The ophthalmologist will adjust a protective eyeware to protect the patient’s eyes from the light. A hydrogel will be applied onto the skin beneath the eyes for protection. A series of five flashes is applied under the lower eyelid. The same procedure is then repeated under the lower eyelid of the other eye.

IPL doesn’t directly affect the Meibomian glands. It is the stimulation of the nerves supplying the glands via a series of chemical reactions taking place after the procedure that stimulates the secretion and contraction of the glands and improves microcirculation.

The treatment effect is cumulative. It generally lasts a week after the first session, between two and three weeks after the second session and six months to two years after the third to fourth sessions. This is a promising mode of treatment to help alleviate or negate the miseries of dry eyes. – By Dr Norazlina Bachik Ng, cataract, refractive and anterior segment surgeon at KPJ Pusat Pakar Mata Centre for Sight