Dry Eye Syndrome
What is dry eye syndrome (Keratoconjunctivitis sicca)?
Keratoconjunctivitis sicca – or dry eye syndrome – is a common dysfunction of the eyes, characterized by its principal symptom of dry eyes. Besides a feeling of dryness, other symptoms include irritation, grittiness and redness of the eyes, as well as the release of a thick discharge from the eyes and blurred vision.
Dry eye syndrome occurs when the glands of the eyes cannot produce tears or produce insufficient quantities of tears, when tears evaporate too quickly or when there is an imbalance in the amount of oil, water and mucus in the tear fluid. Although there are numerous potential causes of dry eyes, some of the most common causes are extended use of contact lenses, long periods spent in front of a TV or computer screen, aging, certain medical conditions (including diabetes, Sjögren syndrome and rheumatoid arthritis) and certain medications (including antihistamines, decongestants and antidepressants).
There are numerous treatment options available for dry eye syndrome, with the choice of treatment dependent on the underlying cause, the symptoms and the severity of the condition. These can range from simple environmental changes and over-the-counter eye drops to medication and – in persistent cases – surgery.
Dry eye syndrome (Keratoconjunctivitis sicca) symptoms
The symptoms of dry eye syndrome are mild in most instances; however, even mild but persistent symptoms can be extremely troublesome and difficult to treat. The symptoms of dry eye syndrome usually affect both eyes.
Common symptoms include:
- Dry, gritty and sore eyes
- Irritation and redness of the eyes
- Temporarily blurred vision (which will usually improve after blinking)
- A feeling of tired or strained eyes
If any of the symptoms of dry eye syndrome persist or cause serious pain, medical attention should be sought.
Causes of dry eye syndrome (Keratoconjunctivitis sicca)
Tears are composed of a mixture of oil, water and mucus – a combination that ensures the surface of the eyes remain smooth and clear, as well as protecting the eyes from infection. Dry eye syndrome is caused when the glands of the eyes are unable create an adequate amount of tears, when tears evaporate too rapidly or when there is an imbalance in the composition of tears.
Deficiency of tears
One common cause of dry eye syndrome is an inability of the glands in the eyes to produce enough tears to keep them moist. Typical reasons for this include:
- Medical conditions including diabetes, rheumatoid arthritis, scleroderma, lupus, Sjögren syndrome, thyroid disorders and vitamin A deficiency
- Certain medications including decongestants; antihistamines; hormone replacement therapy; antidepressants; medications used to treat high blood pressure, acne and Parkinson’s disease; as well as birth control drugs
- Laser eye surgery (this effect is usually temporary)
- Damage to the tear glands from inflammation or radiation
Evaporation of tears
Another common cause of dry eye syndrome is the evaporation of tears at an increased rate. Causes of this can include:
- Dry, windy or smoky environments
- Blinking less often (typically when reading, driving or concentrating intensely)
- Problems with the eyelids such as ectropion (out-turning of the eyelids) or entropion (in-turning of the eyelids)
Imbalance in tear composition
The tear film that coats the eyes is composed of three substances, each with a different role within the eye:
- An oily outer layer (lipid) produced by the meibomian glands which prevents tears from evaporating too quickly.
- A watery middle layer (aqueous) produced by the tear glands which helps nourish the cornea and the conjunctiva.
- A mucous inner layer produced by goblet cells which helps bind water to the eyes, helping them to stay moist.
Dry eye syndrome can result from problems with any one of these layers. For example, the meibomian glands can become blocked, resulting in decreased production of oils or the production of lower-quality oils.
Diagnosing dry eye syndrome (Keratoconjunctivitis sicca)
Those experiencing any of the symptoms of dry eye syndrome – dryness, irritation, blurred vision, etc. – should visit a doctor or ophthalmologist as soon as possible. Based on the symptoms, tests may be done to assess the severity of the symptoms and dryness.
- Fluorescein eye test: Fluorescent eye drops are used to highlight the tears in the eyes, enabling a specialist to monitor how tears are being produced and how quickly they are evaporating. The drops may also show any damage to the surface of the eye.
- Schirmer’s test: Blotting paper is placed over the lower eyelids and left for five minutes. The wetness of the paper determines the diagnosis, with less than 10 mm indicating the presence of dry eye syndrome.
- Lissamine green test: A strip of paper containing a special dye is placed over the surface of the eyes, allowing specialists to identify any damage to the surface of the eye.
Dry eye syndrome (Keratoconjunctivitis sicca) treatment
After being diagnosed with dry eye syndrome, a specialist will recommend a treatment route appropriate to the underlying cause, the specific symptoms and the severity of the condition. There is no cure for dry eye syndrome, but it can be effectively managed.
Treatment may involve:
- Eye drops: Drops to artificially increase the moisture in the eyes is the most common treatment option. These may be prescribed by a specialist but are also available over the counter.
- Medication: The most common drug used to combat chronic dry eye syndrome caused by ocular inflammation is cyclosporine. This anti-inflammatory medication is given as eye drops and helps to increase tear production by the tear glands.
- Medication change: If a medication used to treat another condition is identified as the cause of dry eye syndrome, a doctor may prescribe an alternative.
- Surgery: Surgical treatment is reserved for severe cases of dry eye syndrome. The procedure will usually involve blocking the tear drainage holes in the inner eye using lacrimal (punctal) plugs. This is reversible but can be used as a permanent solution.
Dry eye syndrome (Keratoconjunctivitis sicca) prevention
Prevention of dry eye syndrome may involve regulating environmental conditions and making small lifestyle changes. Avoiding dry climates and using a humidifier to increase the moisture in the air can be effective, as can avoiding smokey and windy conditions. Taking frequent time out while driving, using a computer or reading can help to refresh the tear film and prevent the eyes from drying out.
Dry eye syndrome (Keratoconjunctivitis sicca) FAQs
Q: Are there any home remedies for dry eye syndrome (Keratoconjunctivitis sicca)?
A: Yes, there are a number of home remedies for dry eye syndrome. These include:
- Warm compresses: Irritation can be reduced and the meibomian glands declogged through the application of a warm compress. This treatment consists of wetting a cloth with warm water, placing it over the eyes and gently dabbing the corners of the eyes. This may be necessary every day.
- Hygiene: Keeping the eyelids and areas surrounding the eyes (including the lashes) clean can help prevent dry eye syndrome and ease the condition’s symptoms. A small amount of mild cleanser or shampoo can be used to clean this area. Avoiding excessive touching of the eyes can also help keep the eyes clean.
- Hydration: A person can stay hydrated by drinking large amounts (8 to 10 glasses daily) of water. This can help the eyes stay moist.
- Diet and supplements: A deficiency of certain proteins and vitamins may in some cases contribute to the onset or the severity of dry eye syndrome. In these cases, foods rich in Omega-3 and supplements containing Omega-3 may be recommended as a treatment option. Consuming foods high in flaxseed oil (such as pasta and cereals) or flaxseed oil supplements can also help ease the symptoms of the condition.
If symptoms persist despite the use of any home remedy, or if any adverse effects result, medical attention should be sought promptly.
Q: Should I be worried about blurred vision as a result of dry eye syndrome (Keratoconjunctivitis sicca)?
A: Temporarily blurred vision can be a symptom of dry eye syndrome. Typically, it is little more than an inconvenience and can be managed through various treatment options. However, those who experience blurred vision should seek medical attention, as, in rare cases, it can be a symptom of more serious conditions such as eye disease.
Q: What can I do when my eyes feel dry?
A: If your eyes begin to feel dry during activities such as driving, reading or using a computer, it is a good idea to take frequent breaks to allow the tear film to refresh. You should also remember to blink frequently. Laying a damp cloth over your eyes may also be effective in re-moisturising the eyes.
Q: Is there a surgical method of treatment for dry eye syndrome (Keratoconjunctivitis sicca)?
A: Yes, a minor, non-invasive surgical procedure to insert lacrimal (punctal) plugs can be used to treat dry eye syndrome. These plugs are small devices which are placed into the opening of the tear ducts in the eyes. Lacrimal plugs work by blocking the drainage of tears from the eyes, keeping them lubricated. Lacrimal plugs will generally only be recommended once other treatment methods have proven unsuccessful.
Q: What is the relationship between dry eye syndrome and meibomian gland dysfunction (MGD)
A: MGD is among the leading causes of dry eye syndrome. The condition occurs when the glands responsible for the oily layer of the tear film (located inside the eyelids, with their openings on the edge of the eyelids) cease to function, preventing the oily component of tears from being released and causing the watery component of tears to dry out more quickly. There exists several treatment methods for MGD.
Q: What is the relationship between dry eye syndrome and Sjögren syndrome?
A: Sjögren syndrome is an autoimmune disorder which has as its principal symptoms a dryness of the eyes and mouth. As such, Sjögren syndrome is one of the leading causes of dry eye syndrome.
Ophthalmology Times. “In-office treatments for MGD may provide relief.” May 1, 2016. Accessed April 24, 2018. ↩