Most people will have experienced symptoms of dry eye sometime in their lives. These symptoms include a feeling of dryness, grittiness, redness, itching, stickiness or any combination of these. Occasionally, the appearance of swollen eyelids or styes can be a problem. Less common symptoms are light sensitivity and watering. Occasionally, there are no symptoms at all other than intermittent blurred vision that usually, but not always, improves with blinking. These symptoms continue to recur even with the use of eye drops. If you suffer from some or all of these symptoms, you may have Dry Eye Disease.
The surface of the eye requires moisture to enable you to see clearly. This moisture comes from the Tear Film - a thin layer that covers the eye and is spread over the surface of the eye by blinking.
The Tear Film is itself made up of three main layers:
The mucous layer - a sticky substance called mucin is sticks to the surface of the eye and allows the aqueous layer to stay on without dripping off
The aqueous layer - the watery part of the tear film wets the eye and carries oxygen and other types of nutrition for the cells of the eye surface
The lipid layer - the oily liquid on top prevents the aqueous layer from drying off
A weakness or lack in any of these layers can result in a poor tear film and cause symptoms or irritation described above.
One cause of dry eye symptoms is a condition known as blepharitis. The condition results from a combination of poor eyelid hygiene, altered eyelid gland function and infection leading to chronic inflammation. Treatment of blepharitis involves many of the same modalities and techniques as used in dry eye disease.
A change to the amount or quality of the oily or lipid layer of the tear film, or to the glands that produce the oil or lipid, can lead to MGD. It's often the result of a combination of things.
Age is the most common factor - increasing age results in an increase in MGD. Other factors include:
Symptoms of MGD In the early stages, you might not have any symptoms. As MGD progresses your eyes may burn, itch, or be irritated or dry. It might feel gritty, like you have a grain of sand or dust in your eye. An irritated, inflamed eyelid may be red. Some people have moments of blurred vision that improves when they blink. Symptoms can get worse when you're on the computer for a long time or if the air in your home or office is very dry, either from air conditioning or heating.
The inner rim of your eyelid may appear uneven or rough. This is a classic sign of MGD, but not everyone has it. Often the eyelid margins appear red and swollen as in blepharitis (see above) and it is sometimes difficult to tell whether MGD follows blepharitis or causes it.
Blepharitis and Meibomian Gland Dysfunction are the most common causes of Dry Eye Disease. There are many, many more different causes. These range from eyelid conditions which can cause dry eye symptoms, such as Ectropion/Entropion, some medicines that are prescribed by other doctors, previous trauma, allergic eye disease and others.
If a physical or systemic cause is found, sometimes direct referral to another medical specialist such as a rheumatologist, immunologist or endocrinologist may need to be arranged. Often treatment of the underlying physical cause can help with the dry eye symptoms as the disease improves.
Dry Eye Testing and Diagnosis
Our newly established Dry Eye Laboratory analyses your ocular surface to find the different causes of dry eye. A specialist examination of the eyes, skin, eyelids and eyelashes can determine if there are any local conditions leading to dry eye symptoms.
In the clinic, tests are performed to assess the amount, health and completeness of the tear film to determine whether it is functioning properly. Specialised tests can measure the osmolarity (or saltiness) of the tears as well as the presence of enzymes that point to the cause of the problem, such as some auto-immune conditions. These measurements can later be used to determine how well your eye responds to different treatments. Blood tests can establish if there are any physical problems causing dry eye disease, such as rheumatoid arthritis or thyroid problems.
Glands in the eyelids that produce the lipid layer (or oily part of the tear film) can be damaged by age, inflammation and infection. The reduced function of these glands, known as Meibomian Gland Dysfunction (MGD), will cause rapid evaporation of tears. When MGD is the problem there are specific signs that can be seen on microscopic examination and on tear film measurements. Often, people with MGD also have other skin conditions such as Rosacea but frequently this is not obvious or has not been previously diagnosed.
The tests and procedures performed will establish the exact cause of dry eye disease to best tailor a treatment solution for your condition
Dry Eye Treatment
Artificial eye drops are available from any chemist/ pharmacy to replace the aqueous layer of the tear film. However, these drops treat the symptoms but do not treat the cause of the dry eye. Their use provides temporary relief, requires frequent application and is never-ending. It can be quite a bother to put drops in your eyes and often your spouse or relatives need to be involved. Apart from the inconvenience, these drops are also costly and sometimes result in allergies due to the preservatives in them.
However if the right tests are performed, a specific cause can be found for your dry eye and precise treatment can be directed to fix the problem.
For example, different types of eye drops can be used for allergies, inflammation or auto-immunity. In very severe disease, sometimes a preparation of serum made from your own blood can be used to soothe the eye with great success, when all other treatments have failed.
If there is a local cause, such as if the eye lid is too droopy (also known as ectropion), or if there are in-turning eye lashes scratching the eye surface (or entropion), minor eyelid surgery can permanently fix the problem without the need for eye drops. Occasionally, a plug can be temporarily or permanently used to 'save' tears from draining away when there is an insufficiency of tears. Where there is local infection, antibiotic drops or lid scrubbing techniques can be used.
If MGD is the problem, traditional treatments are available to reduce the problem by the application of heat, pressure, steam or massage. These treatments can be performed by yourself at home (see Self Help page under the Information tab above or click the links) or, if required, as an in-clinic procedure. Whilst these treatments are generally fairy effective, the improvement in symptoms of dry eye disease gained from these is usually short-lived and the treatments have to be repeated frequently, usually daily, sometimes more than once a day.
If longer acting relief from dry eye is desired, Intense Pulsed Light therapy is now available which, when used in the right situation, gives a very high success rate in improving symptoms and reducing or eliminating the need for eye drops.
It is best to have this treatment performed on your eyes early in the disease as in advanced or long standing MGD, there is shrinkage and permanent loss of Meibomian Glands.
IPL treatment is performed in the rooms. It takes about 20 minutes. Firstly a cold gel is spread over the lower eyelids, upper cheeks and bridge of the nose. Eye shields are placed over the upper eyelids to protect them against the bright light. A high intensity light is then applied to the area. No pain is felt, instead a clicking feeling can sometimes be felt on the skin. Several applications are done over each side.
Following this Meibomian Gland Expression (MBX - see below) is gently performed, using wet cotton buds or sometimes a firm instrument, to empty the clogged pores of the oily glands.
Improvement in the symptoms of MGD and dry eye are often felt within the next few days and these improvements generally last much longer, often for years, compared with simple home remedies for MGD.
Meibomian Gland Expression (MBX)
In our clinic, IPL treatment is combined with Meibomian Gland Expression (MBX) - a gentle procedure that unblocks the pores of the eyelid glands that produce the oily layer of tears. After the IPL treatment has been applied to the eyelids, firm pressure is applied to the eyelid margins which results in the compacted oils being squeezed out of the pores - a procedure similar to a "facial" where blocked skin pores (commonly known as "blackheads") are cleared. It takes a couple of minutes to treat each eye so the MBX procedure may take less than 5 minutes and only eye drop anaesthesia is required. This short video demonstrates the procedure:
There is now plenty of scientific evidence for the effectiveness of IPL treatment in dry eye disease. Some articles reporting on research in the area are included below:
Any surgical or invasive procedure carries risks. Before proceeding, you should seek a second opinion from an appropriately qualified health practitioner