What are Dry Eyes?

"Dry eye" is a general term referring to any abnormalities of the tears - anything that makes your eyes dry, sore, gritty or tried can often be called “Dry Eye”. Other names for dry eye syndrome include chronic dry eye, dry eye disease and keratoconjunctivitis sicca. Dry Eye symptoms are different from true Dry Eye Disease - as defined by the International Dry Eye Workshop II in 2017, Dry Eye Disease is......


“Dry eye is a multifactorial disease of the ocular surface characterised by a loss of homeostasis, and accompanied by ocular symptoms, in which tear film instability, hyperosmolarity, inflammation and ocular surface damage, and neurosensory abnormalities, play etiological roles” 

 

Dry Eye Disease has a prevalence of up to 50%. It is a multi-factorial disease it can be influenced by gender, age, environment, medications, co-existing conditions and lifestyle, so the disease, signs and symptoms are in constant flux. Dry eye disease falls into two broader categories of Evaporative Dry Eye and Aqueous Deficient Dry Eye. You can also have “Mixed” Dry Eye, where you have aspects of both types.

Evaporative Dry Eye.

This is typically where your tears evaporate too quickly. Nearly 90% of Dry Eye Disease has an evaporative component. It can have many causes, including:

  • Environmental: low humidity, hot air, dust, wind, reduced blinking (from prolonged visual tasks such as reading and computer work)

  • Eye Lid Inflammation: Blepharitis, Ocular Rosacea, Meibomian Gland Dysfunction (MGD)

  • Lid Surface Anomalies: Ectropian, Entropian, Partial Blinking

Aqueous Deficient Dry Eye.

Less common than evaporative Dry Eye, Aqueous Deficient Dry Eye is where there just aren’t enough tears on the surface of the eye. Again there are many things that can affect this including:

  • Sjogren’s Syndrome: an autoimmune disease where the body attacks the tear glands, affecting their normal function

  • Non-Sjogrens Syndrome: a decrease in tear production caused biologically, eg. Thyroid disease, vitamin A deficiency, herpes eye infection, aging.

  • Medically Induced: a decrease in tear production caused medical eg. Antidepressants, antihistamines, decongestants, diuretics, oral contraceptives and refractive surgery. 

What are the Symptoms?

  • Irritation

  • Dryness

  • Pain & discomfort when blinking

  • Stinging and/or burning sensation 

  • Gritty feeling inside the eyes

  • Eye redness (hyperaemia)

  • Itchiness

  • Mucous discharge 

  • Watery Eyes

  • Increased eye irritation from smoke or wind

  • Achy or Sore Eyes 

  • Strained, fatigued & tired eyes 

  • Contact lens discomfort or intolerance

  • Light sensitivity (photophobia)

  • Blurry vision, particularly first thing in the morning or at the end of the day

  • Fluctuating vision

  • Eyelids 'stick shut' at night

  • Eyelids feel 'heavy'