Specialising in  dry eye treatments
Optometrist David Crystal MCOptom DipTp

Do you have sore dry eyes ?
Learn about the opportunity for long-term relief


 
Dry eye clinic products now available in shop


Tear outflow in dry eyes and sjogrens syndromeEvery wakening second your eyes produce a complex mixture of antibiotic lubricants. Blinking spreads this over the eye's surface before being sucked through two small holes in the nasal corner of your eyelids. These are the tear duct openings or puncta that drain tears to the nose and throat. [ mouse-over to see animation]

If your eyes make insufficient tears the tear film is spread too thinly over the eye's surface. If your tears are chemically imbalanced they evaporate too quickly before the next blink comes along. Either way dry spots appear causing sore eyes.
 

                    How are normal tears produced?

Tears are made from a mixture of secretions from glands at different locations around the eye. Tears have 3 layers: lipid (oily), aqueous (watery) and mucous.  

Dry eyes results from defective tear production

The mucous layer connects with the eye's surface and serves as a bio-glue for whole tear film. It is formed by the secretions of 10 million tiny conjunctival goblet cells living within the white of the eye and inner lid surfaces. 

Overlying this mucous is a
aqueous layer
, produced by one large lacrimal gland which is located just below the eyebrow. During wakening hours, the lacrimal gland pumps aqueous tears at a background level adjusting for environmental conditions. When there is an irritant, extra "crying" tears are made almost instantly. This is why as odd as it sounds many dry eye sufferers experience watery eyes- the lacrimal gland overcompensates for irritation caused by an abnormal tear film. During sleep the lacrimal gland is inactive which is why eyes feel sore and dry upon wakening.

Posterior blepharitis often causes DRY EYES

 

The lipid layer sits on top of the watery layer - sealing the tear film by preventing evaporation. This oil is derived from lipids exuded from twenty three meibomian gland openings along the edge of the eyelids. Blocked meibomian glands cause deficiency in tear lipids and dry eye by excessive evaporation. This is called meibomitis or posterior blepharitis and is a chronic recurring condition.
[click here for video treatment]

 

 

 

                          Can Dry Eye Damage My Eyes ?  

Yes. If untreated, damage to the outer protective tissue of the cornea opens a route of infection with the risk of permanent scarring and sight loss.

         What Causes Dry Eyes ?

Dry eye cases have nearly doubled over the last seven years and the list of lifestyle factors that can dry out your eyes is almost endless...
 


Central heating, air conditioning, dehumidifiers, hairdryers, car windscreen demisting, altitude; air travel, dry climates, wind, air pollution, saunas, spicy foods, alcohol, contact lenses; and activities that decrease blink rate, such as driving, watching TV, computers and reading, all increase tear evaporation as well.
 

Who gets Dry Eyes ?

Although dry eyes can be a side effect of disease, the most common cause is normal ageing. In fact the volume of lubricating background tears is less than half at age 65 than at age 18. Not surprisingly then, dry eyes affects one in five people over 55, but some more than others. People with wider eyes; those with larger than average tear duct openings and people taken dehydrating medicines are worse off...   
 

Medicines may exaccerbate DRY EYES
 


Antidepressants, decongestants, antihistamines, blood pressure medication, diuretics, ulcer medication, tranquillisers, beta blockers, oral contraceptives can all dry out your eyes. 
 

 

Amazingly, many lubricating eye drops commonly prescribed for dry eyes contain the preservative Benzylkonium Chloride which can disrupt goblet cell production of tear mucous. These can actually make a dry eye worse with time. 


Other Causes of Dry Eye
 

Several diseases result in secondary Dry Eye Syndrome:
Rheumatoid Arthritis, Thyroid Abnormalities, Asthma, Sjogren's Syndrome, and Lupus. 

For younger women:
Hormonal changes brought on by pregnancy, lactation, oral contraceptives, menstruation, and post-menopause can cause dry eye conditions.

Laser Eye Surgery:
Dry eyes are a confirmed side effect in 30% of cases.


New treatments for dry eyes.
'there really is nothing better than human tears'
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Several conditions can masquerade as dry eye syndrome and a detailed examination will rule out co-existing conditions, such as blepharitis. Around 70% of patients have dry eyes due to lack of tear volume ( aqueous deficiency ) and 30% have evaporative dry eyes. Many patients have both aqueous and evaporative components to their dry eye and successful treatment depends on targeting the root cause of each.

A fluorescent yellow dye is painlessly introduced into the tears of each eye. Viewed with a video microscope under blue light, any area on the surface of the eye damaged by dehydration glows brightly.

Dye tests for DRY EYES

Tear evaporation rate is measured as the number of seconds after a blink before the tear film de-stabilises and tear volume assessed by analysing the "pool" of tears clinging along the edge of the lower eyelids. The dynamic flow of tears following a blink and their exit through your tear ducts are also assessed. 

An examination with this device is essential as it's the only way to diagnose dry eyes

differential diagnosis of dry eyes

Depending on the cause, Dry Eyes can be treated as a temporary problem or a long-term condition. Either way, tears must be conserved or supplemented in order to provide relief.

Short-Term Relief by Tear Supplements.

For less severe dry eye cases, artificial tears offer immediate relief. Unfortunately, many widely used  bottles of eye drops contain preservatives which can cause a worsening of the dryness with long term use. These agents corrupt conjunctival goblet cells which then fail to produce tear mucous. Often low-grade allergies develop. There really is nothing better than human tears.

TheraTears for dry eyes

Long-Term Relief By Conserving Tears.

In cases of more persistent dry eye symptoms, closure of the tear duct openings, may be the best option. This conserves precious tears by restricting drainage. Your eyes are bathed with your own natural tears without the bother of constantly supplementing the tear film with artificial drops. 

Trial Closure of the Tear Ducts - Collagen Plugs

If your dry eye has a dominant evaporative component to its cause, the case for closing the tear ducts is not clear-cut. In these cases temporary dissolvable plugs are sometimes used.

A cotton bud soaked with anaesthetic is held over the tear duct and a tiny dissolvable collagen plug is painlessly inserted into your lower tear duct. The entire procedure is performed in an optometrist's office in a few minutes. Many patients report immediate comfort.

Collagen Plug for dry eyes

Collagen plugs dissolve within one week. If during this test period you experience relief from dry eye symptoms, you may wish to proceed with the long-term comfort afforded by permanent tear duct closure.  

Permanent Closure of the Tear Duct with Plugs

Closing the tear drainage ducts makes a lot of sense. In effect your own natural tears treat your own dry condition. Unless you have purely evaporative dry eye, plugs will help - its just a question of by how much. Some patients find they can stop using eye drops altogether.

Punctal occlusion, the medical name for closing the tear duct, can be achieved by

  • Laser "welding"                                   Reversible - NO
  • Cautersation "burning"                         Reversible - NO
  • Non-dissolvable silicone punctum plugs   Reversible - YES

Punctal plugs act very much like a stopper in a sink. Placing a tiny silicone insert into the tear duct prevents precious tears being lost. As the tear reservoir builds - the self lubricating process begins.

Punctum Plug on probe just prior to insertion

Punctum Plug in situ

Plugs are the least invasive of the long-term solutions to dry eye with a very high rate of success. They can be inserted easily and painlessly and are medically inert. They can easily be removed if too much tearing is produced in the event your dry eye condition improves at a later date. They are ideal in contact lens cases.

Different plug designs are available in a range of sizes so each patient requires individual assessment.
dry eyes
SmartPlugs


 

dry eyes

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