understanding dry eye

Dry eye is caused by a deficiency in the tear film, a layer that coats the outer portion of the eye. The tear film is very important for lubrication and comfort of the eye, as well as for clarity of vision. The tear film has three main components: a lipid (oil) layer, an aqueous (water) layer, and a mucin layer. Deficiencies in any one of these layers can worsen dry eye disease.

  • There are two main types of dry eye:

    Aqueous deficient dry eye occurs when the lacrimal glands fail to produce enough of the watery (aqueous) component of tears to maintain a healthy surface. This form of dry eye can be caused by systemic disorders, including Sjogren’s syndrome, and certain medications including anti-histamines and decongestants.

    Evaporative dry eye is caused by blocked meibomian glands, which are the glands on the eyelid responsible for making the oil layer of the tear film. The oil layer is responsible for keeping our tears on the surface of the eye. When there is a lack of oil, our natural tears evaporate from the surface of the eye. Dysfunctional meibomian glands are a form of blepharitis , a condition characterized by chronic inflammation of the eyelids.

    It is important to figure out which form of dry eye you may have because each type has different treatment options. Many times, aqueous deficient and evaporative dry eye can be found in the same patient.

Dry Eye symptoms may include:

  • Dryness, grittiness, or scratchiness
  • Soreness or irritation
  • Burning or watering
  • Eye fatigue
  • Blurry vision

Blinking is very important for the maintenance of the tear film. When performing activities, such as reading or working on a computer, we blink less frequently, which can aggravates the symptoms of dry eyes. Environmental factors can also worsen dry eye symptoms including dry weather, wind, cigarette smoke, fumes, and dust.

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At NH Eye Associates, we believe in a comprehensive approach to managing your dry eye.

Treatment strategies are based on the type of dry eye you have and the severity of your condition. Our doctors have extensive experience diagnosing and treating dry eye and will work with you to find the best treatment options available.

Click here to find out more about the treatments we offer