Dry Eye

Dry eye is possibly one of the most common reasons for a non-routine visit from a patient. It can affect all age groups and can be an ongoing condition or linked to another eye problem.

Dispensing opticians are ideally placed to give advice to patients on this condition and contact lens opticians and optometrists are able to use diagnostic stains to help ascertain the type of dry eye the patient is presenting with.

Dry eye is a huge topic and it is not the intention here to cover all areas of this however it is important to note the following:

The tear film is made up of three layers and it is deficiency in one or more of these layers which gives rise to the signs and symptoms of dry eye. The outer layer is the lipid layer, produced by the Meibomian glands within the eyelids which stops the evaporation of the next layer, the aqueous layer produced by the lacrimal glands. Protecting the epithelium of the cornea and providing lubrication is the third layer, the mucin layer.

Deficiency in the lipid layer is likely to lead to evaporative dry eye which can lead to a deficiency in the aqueous layer. Likewise, a decrease in tear production by the lacrimal glands will cause aqueous deficiency dry eye.

The DEWS II report is an excellent resource for practitioners.

Certain patients are at more risk of dry eye disease such as those with diabetics, patients suffering with rheumatoid arthritis, lupus or contact dermatitis.

Signs/Symptoms

  • Dryness/foreign body sensation
  • Sore, pink/red eyes
  • Feeling of fatigue
  • Burning sensations
  • Photophobia
  • Blurred or fluctuating vision that improves on blinking
  • Reflex watering
  • Eye strain

Causes

  • Aqueous deficiency
  • Lipid deficiency
  • Environmental factors such as air conditioning, VDU work
  • Contact lens
  • Hormonal changes
  • Blepharitis
  • Rosacea/ seborrheic dermatitis
  • Medication
  • Refractive surgery
  • Sjogren’s Syndrome
  • Chemotherapy
  • Lid malformities
  • Thyroid disease
  • Abnormality of blink
  • Allergic eye disease
  • Vitamin A deficiency
  • Birth control pills

This list is by no means exhaustive and careful questioning of the patient is important in discovering any pre-disposing factors for dry eye.

Treatment

Treatment is multifactorial and can be dependent on the type of dry eye.

  • Environmental changes- air conditioning, VDU work, central heating all play an important factor in dry eye management.
  • Dry eye drops- these are tailored to the different types of dry eye therefore practitioners should be aware of which of the products they supply are aimed at aqueous deficiencies, lipid deficiencies or a multifactorial approach.
  • Hot compresses can be useful in Meibomian gland dysfunction however heated eyebags are more efficacious due to the ability to maintain a level of heat for the required time.
  • Hydration
  • Diet-Flax seed oil/ omega 3/oily fish- have been shown to help improve the quality of the lipid layer (see DEW2 report linked above)
  • Switch away from any preserved eye drops to a preservative free option. If the drops are prescribed, then advise the patient to consult the prescriber before making any changes.
  • If contact lens related considering switching to silicon hydrogels/preservative free cleaning solutions/ daily disposable silicon hydrogel lenses.
  • Blepharitis/Meibomian gland dysfunction (MGD) is a common cause of lipid deficient dry eye and therefore treatment for blepharitis should be investigated (see Blepharitis)
  • The 20:20:20 rule is good advice for patients using VDUs and can help alleviate some dry eye symptoms- every 20 minutes stop and look at and object 20 feet away for a good 20 seconds- if they can practice fully blinking during this time then that is ideal.

Red Flags

  • Monocular- may be indication of foreign body
  • Sudden onset
  • Associated dry mouth
  • Severe pain- consider ulcer
  • Associated red eye increasing
  • Halos around lights
  • Patients who have used dry eye treatments for over 6 weeks without improvement should be referred to a dry eye specialist, minor eye conditions service/CUES or HES.

When one or more of these red flags is raised, a conversation with another registrant in practice should take place following which appropriate referral or management should be actioned and noted. If there are no other registrants in practice then contact should be made with colleagues elsewhere or contact should be made for advice to the local Hospital Eye Service (HES).