What is Dry Eye?
Do you ever wake up in the morning and it feels like you have sand in your eyes? Or you find yourself over blinking causing tears to form? Then you most likely have dry eyes!
Dry Eye occurs when the eyes are unable to produce adequate lubrication to the ocular surface. The two main types of dry eye include Meibomian Gland Dysfunction (also known as Evaporative Dry Eye) and Aqueous Deficient Dry Eye. A condition known as Blepharitis can also cause dry eye symptoms.
Dry Eye Symptoms
Common symptoms of Dry Eye include eye dryness, watering, stinging, burning, grittiness, redness and light sensitivity. People may feel like they have something in their eyes or like their eyes are tired or heavy. Disruption to the tear film may also cause blurry vision and difficulty focusing.
Dry Eye Causes
There are many possible causes of Dry Eye Disease. Some of the most common include:
- Environmental factors: indoor air conditioning or heating, sudden changes in the weather (windy conditions)
- Age: tear production begins to reduce beyond the age of 50
- Gender: women are more at risk, particularly those with hormonal changes due to pregnancy, birth control or menopause.
- Medical conditions: Sjögren’s Syndrome and other autoimmune diseases.
- Medications: most anti-depressants, birth control, antihistamines and hormone replacement therapy.
- Sensitivity to preservatives in many eye drops.
- Eyelid issues such as ectropion where the eyelid rolls away from the ocular surface.
- A diet low in omega-3 and vitamin A.
- Allergic eye disease and hay fever.
- Poor hydration/low water intake.
- Contact lenses.
- Eyelash extensions.
- Excessive eye makeup.
Dry Eye Syndrome
Dry Eye Syndrome is a term that encompasses multiple conditions which may lead to dry eye symptoms. The eye’s tear film is comprised of three layers; the aqueous (water) layer, the lipid (oil) layer, and the mucin layer. A break down in any of these components may lead to an unstable tear film and therefore Dry Eye.
Aqueous Deficient Dry Eye results from a lack of water secreted from the lacrimal gland, the gland that we use when we cry. Aqueous deficiency accounts for approximately 10% of these cases and is usually a result of a medical condition known as Sjögren’s Syndrome or may be a result of some oral medication.
Meibomian Gland Dysfunction results from a lack of oil (or meibum) being secreted onto the ocular surface. When we blink, the Meibomian/oil glands that line our eyelids should secrete oils into our tear film. In people with Meibomian Gland Dysfunction, these Meibomian glands become blocked and are unable to release any oil. Without this oil, the tear film evaporates too quickly leaving the ocular surface exposed. This can cause a sharp stinging or burning sensation on our eyes.
The eyes then try to protect the ocular surface by releasing excess watery tears which is why people with Dry Eye Syndrome often have constantly wet or watery eyes.
Anterior Blepharitis results from an overgrowth of the normal bacteria that live on our eyelids and eyelashes. This causes a dandruff like material to build up on the base of our eyelashes. This material can flake off and fall into our eyes causing irritation. Read more in our blog post on Blepharitis.
Eye Drops for Dry Eye
There are hundreds of eye drops available in today’s market for Dry Eye and some are much better than others. This can make choosing the right drops for you very confusing. It is best to have a dry eye appointment so your optometrist can select the best ‘artificial tear’ also known as eye drops, for the type and severity. Most drops aim to improve the aqueous layer of the tear film while others aid the lipid layer. Generally, preservative free lubricant eye drops are the best option for most people as the preservatives in many of the bottle formulations can exacerbate one’s dry eyes.
Dry Eye Treatment
For aqueous Tear Deficiency, treatment is focused on supplementing the tear film with preservative free ocular lubricants in the form of drops, gels, or ointments. The aim is to prevent tear evaporation.
Another option for this condition is punctal plugs. These are small devices which are inserted into the drainage duct in our bottom eyelids to minimise the drainage of tears from our eyes. Other treatment options include modifications to your environment such as increasing humidity with a humidifier, minimising the use of the air conditioner, minimising screen time, and conscious heavy blinking.
Some eye drops are also useful in the treatment of Meibomian Gland Dysfunction. Drops designed to mimic the lipid layer work well in this condition such as Systane Balance or NovaTears. Applying heat to the eyelids in the form of an Opti-Soothe Eye Mask aims to melt the lipids within the Meibomian glands to allow for better secretion. Massaging the eyelids after using the eye mask assists with this process. Increasing your intake of Omega-3’s to your diet is also helpful.
Treatment for Anterior Blepharitis aims to minimise the bacterial load around our eyes. This is best done with regular use of Blephadex eyelid wipes or Blephadex eyelid foam cleanser. This is also a great product for everyday removal of eye makeup which can build up in the Meibomian glands and cause blockages.
Ciclosporin is a very effective eye drop which can be prescribed for severe cases. It can be compounded into monthly bottles and are also available in single use doses with assistance of the Pharmaceutical Benefits Scheme under the brand name Ikervis.
Without the recommended treatment for your dry eyes, it could result in the following:
- Eye infections
- Bacterial keratitis (infection of the cornea)
- Eye inflammation and blocking of the tear duct
- Scarring of the eye
And in extreme, very rare cases, vision loss
Dry Eye Examination
Questionnaire: This allows us to grade the severity of your symptoms and to monitor for change over time. By completing the questionnaire before and after treatment allows us to gauge the effectiveness over time.
Tear Osmolarity: Our I-Pen tear osmolarity test measures the osmolarity of your tears. In simple terms, this means how many salt particles are in your tears. People with higher tear osmolarity are more likely to have more severe dry eye signs and symptoms.
MMP-9 Testing: MMP-9 is an inflammatory marker that can determine if patients have Dry Eye Syndrome.
Meibography: Specialised equipment is used to clinically observe and photograph the structure and size of the Meibomian glands (oil glands) lining our eyelids. We have approximately 20-30 Meibomian glands lining our lower eyelids and 30-40 in our top eyelids. In patients with chronic Meibomian Gland Dysfunction, the glands can become blocked and damaged leading to gland collapse and death. This equipment allows us to visualise the quantity and health of the remaining functioning glands.
If severe dry eye goes untreated, it is possible for it to lead to more complicated eye issues. If you are experiencing any of the symptoms above, it is vital that you book an eye appointment with your optometrist.