Typical symptoms of dry eye syndrome are dryness, burning and a sandy-gritty eye irritation that gets worse as the day goes on. Symptoms may also be described as itchy, scratchy, stinging or tired eyes. Other symptoms are pain, redness, a pulling sensation, and pressure behind the eye. There may be a feeling that something, such as a speck of dirt, is in the eye. The resultant damage to the eye surface increases discomfort and sensitivity to bright light. Both eyes usually are affected.

Symptoms of dry eyes and dry eye syndrome include:

• Burning sensation
• Itchy eyes
• Aching sensations
• Heavy eyes
• Fatigued eyes
• Sore eyes
• Dryness sensation
• Red eyes
• Photophobia.(light sensitivity)
• Blurred vision

• Another common symptom is something called a foreign body sensation — the feeling that grit or some other object or material is "in" your eye.
• And as odd as it may sound, watery eyes also can be a symptom of dry eye syndrome. This is because dryness on the eye's surface sometimes will over-stimulate production of the watery component of your tears as a protective mechanism. But this "reflex tearing" does not stay on the eye long enough to correct the underlying dry eye condition.
• In addition to these symptoms, dry eyes can cause inflammation and (sometimes permanent) damage to the surface of the eye.
• Dry eye syndrome also can affect the outcomes of LASIK and cataract surgery.

An adequate and consistent layer of tears on the surface of the eye is essential to keep your eyes healthy, comfortable and seeing well. Tears bathe the eye's surface to keep it moist and wash away dust, debris and microorganisms that could damage the cornea and lead to an eye infection.

A normal tear film consists of three important components:

• An oily (lipid) component
• A watery (aqueous) component
• A mucous-like (mucin) component

The only way to know for sure if you've got dry eye syndrome is to have your eye doctor perform detailed Dry Eye Diagnostic during an eye exam.

• Symptoms alone are poor predictors of the presence and severity of dry eye disease.
• Symptoms can vary significantly from person to person, and may even be affected by personality type. Some people with only minimal or mild dry eyes may feel their eyes are very bothersome, while others may have significant dry eye problems and not consider their symptoms significant enough to see an eye doctor (or they may not experience dry eye symptoms at all).

Only a careful examination and detailed diagnosis of your eyes by an optometrist or ophthalmologist can reveal the presence and severity of dry eye syndrome and help your eye doctor determine the best type of dry eye treatment to keep your eyes healthy, comfortable and seeing well.

A number of factors can increase your risk of dry eyes. These include:

• Computer use. When working at a computer or using a smartphone or other portable digital device, we tend to blink our eyes less fully and less frequently, which leads to greater tear evaporation and increased risk of dry eye symptoms.
• Contact lens wear. Though it can be difficult to determine the exact extent that contact lens wear contributes to dry eye problems, dry eye discomfort is a primary reason why people discontinue contact lens wear.
• Aging. 
• Menopause. 
• Indoor environment. Air conditioning, ceiling fans and forced air heating systems all can decrease indoor humidity and/or hasten tear evaporation, causing dry eye symptoms.
• Outdoor environment. Arid climates and dry or windy conditions increase dry eye risks.
• Frequent flying. The air in the cabins of airplanes is extremely dry and can lead to dry eye problems, especially among frequent flyers.
• Smoking. 
• Health conditions. Certain systemic diseases — such as diabetes, thyroid-associated diseases, lupus, rheumatoid arthritis and Sjogren's syndrome — contribute to dry eye problems.
• Medications. Many prescription and non-prescription medicines — including antihistamines, antidepressants, certain blood pressure medications and birth control pills — increase the risk of dry eye symptoms.
• Eyelid problems. Incomplete closure of the eyelids when blinking or sleeping — a condition called lagophthalmos, which can be caused by aging or occur after cosmetic blepharoplasty or other causes — can cause severe dry eyes that can lead to a corneal ulcer if left untreated.

Ocular Surface Analyzer is the new instrument of individual analysis of tear film that allows to do a quick detailed structural research of the tear composition.

Aqueous layer analysis

Thanks to I.C.P. OSA it is possible to identify the type of DED (Drye Eye Desease) and determine which layers can be treated with a specific treatment, in relation to the type of deficiency. The aqueous layer is evaluated through the non invasive “Tear Meniscus” test, classifying it in different categories and possible issues related to this. The measurement (in mm) allows  the direct evaluation of this layer quantity, and it is comparable to the Schirmer’s Test with the difference that “Tear Meniscus” is without invasiveness and it does not take four minutes (only take a photo).

Mucous layer analysis

The stability of mucin layer and the whole tear film is measured through BUT or NIBUT, thanks the use of right grids that are projected on the cornea to evaluate (manually or automatically) the time when tear film breaks up.

Lipid layer

Through the “Interferometry” examination, the OSA can valuate the quantity and the quality of the lipid component on the tear film. It project an image that is comparated with the international grading scale of interferometry, in order to distinguish a pathologic dry eye from a border line eye or a healty eye.