Dry Eye

What is Dry Eye?

Dry eye or keratoconjunctivitis sicca is one of my favourite optometry topics; not only do I suffer this myself but it is also the most common eye condition I diagnose and treat in my practice on a day to day basis. 

 It may cause any or all of the following symptoms; 

·         Gritty or itchy eyes

·         Foreign Body sensation

·         Sore, stingy or red eyes

·         Watery eyes

·         Tired eyes

·         Variable vision or glare sensitivity 

 

What are the causes?

Generally there a 2 types of dry eye.  

·         Aqueous deficiency; the lacrimal gland fails to produce enough basal tear layer.

·         Evaporative dry eye; due to (MGD) meibomian gland (oil glands of the eyelids) dysfunction             resulting in a reduced oily component to the tears. 

Causes may include; 

·         Age; evaporative dry eye is more common as we get older

·         Gender and Hormones; with females more commonly affected than men, menopause, and             hormone imbalance being associated.

·         General health; Rheumatoid arthritis, thyroid dysfunction, Sjogren’s syndrome, Rosacea.

·         Medication; antihistamines, antidepressants, some blood pressure medicines, Parkinson's               medication and oral contraceptives.

·         Environment; dry, dusty or windy climate, air conditioning, contact lens wear and computer               use.

 

How is it diagnosed?

 Your eye care professional can diagnose dry eye by way of the following; 

·         Asking specific questions with relation to your symptoms

·         Measurement of the aqueous (watery layer) of your tears

·         Measurement of your natural tear break up time; basically how long it takes between blinks               before your tear film begins to evaporate

·         Thorough assessment of your eye lids, tear film, cornea and conjunctiva using specific                       diagnostic dyes and a slit lamp biomicroscope to detect micro changes to the ocular surface.

·         Careful assessment will be made to ensure there is no underlying condition causing your                   symptoms such as foreign body, infection, allergy or eye cancer.

 

Dry Eye Treatment

Depending on the cause there are a number of measures that can be taken to help relieve your dry eye;

Self Help for Dry Eye

Improve your Blink; consciously blink more frequently, particularly when reading and using a computer or digital device. Consider the quality of your blink, if your eyes begin to feel gritty; relax and take 10 slow, complete blinks.

Get Hydrated; you can hydrate your eyes from both the inside and out by ensuring your own fluid intake is sufficient while reducing alcohol and caffeine. Tear supplement eye drops can also help to replenish the tear film while some include electrolytes to enhance the hydration effect. You can also wear wrap around glasses which have a ‘moisture seal’ creating a more humid environment for eyes and increasing comfort.

Clean me; remove eye make-up thoroughly to ensure there is no debris clogging the meibomian glands. Furthermore, if you have been told you have blepharitis, a special eyelid cleanser may be recommended to clean the lids and lashes thoroughly.

Warm me up; Hot compresses work exceptionally well for evaporative dry eye. Your Optometrist will be able to supply you with a special heat pack for your eyes to maximise the effect. Otherwise just try a warm facecloth held over your eyes for up to 10 minutes, twice daily.

Prescribed help

Topical eye drop medication; this may include an anti-inflammatory eye drop, specific tear supplements or even autologous eye drop serum- eye drops made from a small amount of your own blood product!

Oral medication and supplements; certain oral antibiotics can reduced eye lid and meibomian gland inflammation improving the eye appearance, comfort and tear film consistency. Furthermore clinical trials have shown evidence that a combination of both fish and flaxseed oil supplements can reduce dry eye symptoms. 

Still not enough?

Punctal Plugs; A small sterile device is inserted into one of the small openings of the tear drainage ducts that are located in the inner corner of the upper and lower eyelids. These help to retain the tears in the eye for longer before draining away.

Blephasteam treatment; An in office ‘facial for the eyes’ which involves wearing specialised steam goggles for a 10 minute period. This gently helps to soften the oil within the blocked meibomian glands along the edge of each eyelid. This may then be followed by manual expression of the oil from previously blocked glands.

IPL treatment; the use of intense pulsed light may help to treat ocular rosacea; a condition whereby tiny blood vessels become dilated along the eyelid margin with associated meibomian gland dysfunction.

 

myopia- what we know.

What is myopia?

Myopia or shortsight, occurs when the eye focuses light too quickly resulting in clear near vision but distance blur. This usually occurs when the eyeball is too long.  At birth the eye tends to beshort, making us longsighted. This gradually reduces as the eyeball grows to normal length. However, for some children, the eyeball continues to grow and myopia develops. This may also occur in teenage years, or the early twenties.

Risk factors of myopia and myopic progression

Age; the younger the onset (under 10 years) the greater risk of progression.

Ethnicity; East Asians have the highest risk of becoming myopic

Genetics; With one myopic parent a child has up to 25% risk of becoming myopic, with 2 myopic parents, risk increases to up to 40% while if neither parent is myopic the risk is < 10%.

Lifestyle and environment; living in the city as opposed to a rural lifestyle along with reduced time spent outdoors combined with high levels of near work increase a child’s risk of myopia

Seasonal variation; there is less myopic progression in summer months

The outlook for myopia

About a 1/3 of the world are myopic with 3 %  having high myopia ( over -5.00D), however it is estimated that by 2050 , more than ½ of the world’s population will be myopic with 10% being highly myopic.  High myopia carries an increased risk of eye disease and therefore blindness.

Myopia control

While there is no cure for myopia, spectacles, contact lenses and refractive surgery can improve vision. However, there is now good robust evidence to show what may help actually reduce onset or at least slow progression of myopia;

10 hours of outdoor activity weekly; reduces risk of becoming myopic and possibly slowing progression.

Atropine therapy;  a low dose 0.01% pharmaceutical can be prescribed for night time use with little or no side effects. Atropine relaxes accommodation (the focusing system of the eye) and appears to be a viable option for slowing progression

Spectacles; Full myopic correction is indicated; in fact under-correction of myopia may actually increase myopic progression. Specialised spectacle lenses which reduce the focusing burden of the eye with prolonged near work can be indicated in some cases; helping to reduce myopic progression. 

Contact lenses; Specialised soft lenses have been shown to reduce progression. Furthermore, overnight wear of rigid lenses which reshape the cornea ( a process known as orthokeratology) may be indicated.

If you have concerns about your myopia or your child’s risk of myopia contact us today to discuss your best options

Specific guidelines to optimise your macular health

The Age Related Eye Disease Study (AREDS) and the subsequent (AREDS2) were 2 major clinical trials conducted by the National Eye Institute in the USA. These studies identified a specific formula of antioxidants that was effective in slowing the progression of age related macular degeneration (MD). To date, these are the only studies for which there is good, long-term evidence for the effects of high dose nutrients for people who are diagnosed with MD.

The study showed that taking the AREDS formula every day significantly reduced the relative risk of progression of MD and delayed visual loss. The results in a nutshell;

•        Those with intermediate stage MD reduced their risk by approximately 25%.

•        Those with late stage MD in one eye reduced their risk by approximately 20%.

•        Beta-carotene  and omega 3 supplements showed no effect in reducing MD risk

•        Lutein and Zeaxanthin intake has a clear link with reduced MD risk

Based on these results we at Eyes of Howick recommend the AREDS2 formula to our patients with intermediate or late stage MD.

AREDS2 FORMULA

·         Vitamin C 500mg

·         Vitamin E 400 iu

·         Lutein 10mg

·         Zeaxanthin 2mg

·         Zinc 80mg

·         Copper 2mg

While there are several brands of supplements available which align with the AREDS2 formula, it is important to note that a supplement is not a cure for MD, nor does it stop or reverse damage caused by MD. It is important to read the label to understand how many tablets need to be taken to match the AREDS formula.

One of the key differences between the AREDS and AREDS2 formula is the omission of beta-carotene from the later study due to concerns about it increasing the risk of cancer in smokers. People who smoke or have smoked or who have asbestosis should not take a supplement that contains beta-carotene. Furthermore, if beta-carotene and lutein is taken concurrently, the absorption of lutein is lowered.

While the AREDS2 study found no link between supplementary omega 3 fatty acids and reduced risk of MD, it is still advised to eat fish 2-3 times per week. It should be noted that there are other benefits of taking an Omega 3 supplement if your fish intake is low such as to help with dry eye and reduce risk of glaucoma.

For those patients who have a risk factor for MD such as family history, over 50 years of age, early macula changes and if their diet is poor in dark green leafy vegetables, a daily lutein supplement of 6-10mg  is appropriate.

And if you want to ensure your diet is the best it can be to optimise your eye health here are some guidelines to get you started.

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*Recommended Daily Intake (RDI) per National Health and Medical Research Council (NHMRC). The RDI refers to the amount of a specific nutrient (vitamins, minerals, energy or protein) considered adequate to meet the nutritional requirements of healthy people. The RDI was formulated as a way to help prevent nutritional deficiency diseases in healthy people, and does not address theextraordinary needs of people who smoke, suffer from ill health or are on medication

 ‡ There is no standard daily intake for lutein. 6 mg is the accepted amount in lutein supplements.

# The measure mcg is a microgram. 1 mg = 1000 mcg.

Please note that Kale and some other green vegetables are high sources of Vitamin K which can interfere with the anticoagulant effect of medications such as warfarin. Always consult your healthcare professional if undertaking a major dietary change.