What will my baby’s eye colour be?

Brown, green, blue, amber, hazel, gray… what eye colour will your baby have?  Eye colour is dependent on the complex genetics of the parents.  It is believed that 3 genes determine eye colour and only 2 are well understood.

Babies are usually born with little or no pigment in their eyes and are therefore very light.  As they develop, their cells begin to produce melanin (pigment) which changes the colour of their eyes, skin, and hair.  The amount of melanin in the eye is based on our genes.  In general the genes for brown eyes is dominant over the genes for blue eyes.  When the pairs of genes from both parents combine, depending on what combination of genes are passed on (both dominant and non-dominant), they will produce a certain eye colour and shade for their offspring.  Based on this, you can see why multiple possibilities exist.  It is even possible for 2 blue-eyed parents for have a brown/hazel eyed child.

Your eye colour should never change dramatically.  See your eye doctor immediately if this occurs because it could indicate certain eye diseases including pigmentary glaucoma, Horner’s syndrome, and Fuch’s heterochromic iridocyclitis.

Dr. Jessica Chang, OD

drchang@avenueeyecare.com
Vancouver Kerrisdale Optometrist

Contact Avenue Eyecare to book your appointment today.

7 things you didn’t know about your eyes

Here are riveting facts you may not know about your eyes…

7.   Most people need reading glasses when they get older
If your prescription is between -1.00 to -3.00, you may get away with reading glasses by removing your distance glasses.  For the rest of us, the focusing eye muscles will get weaker and this condition is called presbyopia.

6. The lens in your eye is quicker than any camera lens
An average camera lens takes at least couple seconds before it can focus on an object.  Your eye is able to focus in milliseconds.

5. You blink approximately 15,000 times a day.
This is to ensure that your eyes stay moist.  This process allows you to maintain a clear image.  If you stare at the computer a lot, this number may decrease down to 10,000 times a day.

4. Everyone gets cataracts if you live long enough
The lens inside your eyes is like an egg.  If you cook an egg, it’ll become cloudy and white.  Over time, the UV rays from the sunlight will cook the lens in your eyes and you will eventually develop a cataract.

3. Diabetes is often first detected during an eye exam
People suffering from Type II diabetes are usually symptom free.  A comprehensive eye exam can detect early signs of diabetes from the tiny hemorrhages on your retina.

2. 20/20 vision is not best vision you can see
Most people should be corrected to 20/20 vision.  However a select few is able to see one line lower than 20/20.  That line is 20/15.

1. Your Eyes water when they are dry
The eye will tell the brain that the eye is dry.  When this happens, the brain signal the lacrimal gland (tear gland) to release tears to the eyes.  Sometimes this occurs in excess, and it will cause your tears to roll down your face.

Dr. Sherman Tung, OD FAAO

drtung@avenueeyecare.com
Vancouver Kerrisdale Optometrist

Contact Avenue Eyecare to book your appointment today.

What’s with Hillary Clinton’s new glasses?

I was catching up on my TV shows and recently watched the much anticipated interview of Hillary Clinton and Barack Obama on 60 minutes a few days after his 2nd Presidential Inauguration.  I couldn’t help but notice the glare from the studio lights on Hillary’s left lens of her glasses.  When I looked a little more closely, I realized the glare was due to the fact that she had fresnel prism on her lens.

What is fresnel prism and why do we prescribe it?

Prism is added to a patient’s prescription when they experience double vision because it helps shift images together by bending light.  Prism can be permanently ground into eyeglass lenses and would not be noticeable to most people.    Fresnel prisms are made of up several tiny prisms lined up base to apex on a piece of thin adhesive plastic.  They are temporary press-on prisms that come in a variety of powers.  It is used in cases when the amount of prism needed is anticipated to change over time because it is much more economical than making an entire new lens every time there is a change.

Hillary Clinton’s double vision caused by her concussion will get better over time, and that is likely why she has temporary fresnel prism on her glasses.

If you are experiencing double vision, it is always a good idea to seek help from your eyecare professional as soon as possible.

http://www.huffingtonpost.com/2013/01/25/hillary-clinton-glasses_n_2550715.html

Dr. Jessica Chang, OD

drchang@avenueeyecare.com
Vancouver Kerrisdale Optometrist

Contact Avenue Eyecare to book your appointment today.

How to improve your golf game

I recently attended a sports vision lecture about how to improve your patient’s golf game.  If you’re a golfer, you know how little things like changing your swing or a club can make a big difference.  When you think about what is involved with golf, it’s easy to see that there are many visual skills necessary to excel at this sport.  Golf depends on good vision and eye-body coordination.  Here’s a breakdown of things you can do to ensure your vision is optimized for golf.

1.  Visual Acuity:  We want both eyes to ideally be 20/20 or better so you can see your ball land on the green.  Contact lenses that fit a little tighter are ideal to minimize movement of the lens when you blink or move your eye.  Glasses can be problematic because they may fog or slip down your nose while you play.  Pro golfers such as Tiger Woods choose to have laser refractive surgery which is a great option for the right candidate.

2.  Contrast Sensitivity:  This is refers to our ability to discern between different luminance levels.  This is important when trying to read the green when we putt.  It declines with age due to factors such as cataracts, dry eyes, or diabetic retinopathy.  A routine eye exam can detect these conditions.  There are also certain exercises we can do to train contrast sensitivity.

3.  Appropriate Tints:  Sunglasses/tinted eyewear can help with things such as glare and reading the green.  Neutral greys and greens are good in sunny conditions.  Nike has also developed a purple-ish tint specific for golf called “Max Golf Tint”.  When dusk sets, consider an amber tint.

4.  Depth Perception:  This is often assessed during an eye exam at near, but for golf it should also be assessed in the distance.  This skill can be optimized with optimal visual acuity in both eyes and good binocular function.  There are eye exercises that can enhance depth perception abilities.

The weather is warming up so dust off those clubs and happy golfing!

Dr. Jessica Chang, OD

drchang@avenueeyecare.com
Vancouver Kerrisdale Optometrist

Contact Avenue Eyecare to book your appointment today.

Protecting your eyes from the snow blindness

I just came back from a ski trip and I realized many people don’t know that the combination of  sun & snow is much worse than sun & sand.  The damage to your vision and eye health is greater because the intensity of glare and UV off of the snow is much worse.  Did you know that snow reflects 80% of the sun’s rays but water only reflects about 10%?  For this reason, snow blindness is a common problem that can easily be avoided.  Snow blindness is a condition where intense UV rays reflected off surrounding snow damage your exposed cornea.  The symptoms include redness, tearing, soreness, swollen lids, blurred vision, and discomfort.  Here are some tips on protecting your eyes while you’re enjoying yourself on the slopes…

1.  Wear ski goggles to avoid snow blindness, even on a cloudy day.  They protect you from incoming UV rays from all directions (unlike regular sunglasses and glasses).

2.   Make sure your ski goggles are well vented to let moisture escape, this avoids problems with fogging and moisture freezing on your glasses.

3.  Keep  your eyes well lubricated with artificial tears, especially if your eyes have mild UV damage/snow blindness.  This promotes your cornea to heal more quickly.

4.  Wear sunscreen on your face and around your eyes

5.  Wear the appropriate tint for your ski goggles to enhance your vision in different conditions

If for some reason you do experience snow blindness, please see your eyecare professional as soon as possible.

Dr. Jessica Chang, OD

drchang@avenueeyecare.com
Vancouver Kerrisdale Optometrist

Contact Avenue Eyecare to book your appointment today.

Smoking and Eye Health

I hope everybody enjoyed their holidays. It’s the start of the new year and many of us have made resolutions that we want to keep. Quitting smoking would be high on the priority list for some of us. It has been well documented that smoking has a strong association with lung cancer and cardiovascular disease among the general population. However, according to surverys, only 9% of the population knows that smoking can be detrimental to your eye health. So what are some ocular complications from smoking?

1. Age Related Macular Degeneration (ARMD) – Smoking is the strongest epidemiolgical risk factor for developing ARMD. The understanding of the mechanism is limited but the most likely causes are oxidative damage and pathological vascular changes.

2. Dry Eyes – Smoking can damage goblet cells that are important in producing the oily layer for our tears.

3. Graves’ Ophthalmopathy – Cyanide in the cigarettes can act as an anti-thyroid agent. This directly inhibits the iodide uptake and hormone synthesis. When this happens, this may lead to proptosis (bulging of the eyeballs)

4. Glaucoma – Some studies have shown a 2.9 times increase in developing glaucoma. Smoking has also shown that it may increase your eye pressure by almost 5.0 mmHg.

5. Cataracts – There is an increase of nuclear sclerotic cataracts and subcapsular cataracts. The free radicals that are in cigarettes may trigger the development of cataracts sooner than the general population.

Your optometrist can check if there is any ocular health damage due to smoking. If you need help to quit smoking, talk to your optometrist or your family doctor.  Websites such as www.smokershelpline.ca or www.gosmokefree.gc.ca may also help.  At Avenue Eyecare, we are here to help you with all your eyecare needs.

Dr. Sherman Tung, OD FAAO

drtung@avenueeyecare.com
Vancouver Kerrisdale Optometrist

Contact Avenue Eyecare to book your appointment today.

How to slow down myopia (nearsightedness)

Parents are often worried about their children’s nearsightedness (myopia) progression.  Nowadays, approximately 40% of children will develop myopia compared to 25% during the 1980′s.

There are 3 different types of myopia

1. Pathological myopia – Occurs early in life with little progression (Congenital)
2. School myopia – Begins between ages 8-12 and progresses dramatically
3. Adult-onset myopia begins at age 18 or older

Genes vs. environment

Studies have shown that myopia has strong genetic and environmental components.

1. Genetics – Studies have shown that a child with parents without myopia has a 10% chance of developing myopia.  With one parent, it’s 25% and with two parents, it’s 35%.
2. Environment – In school settings, progression of myopia was increased by 50%.  Lack of outside sunlight exposure is a strong risk factor for development of myopia

Progression and treatment

1. Bifocal and progressive addition lenses
According to the COMET study, children that wore single vision had a mean progression of -1.48D in 3 years compared to the progressive group of -1.28D.  Even though it’s statistically significant, clinically, it’s not.  This means that wearing bifocals or progressives may not help prevent further myopia.

2. Undercorrection
Sometimes parents may to have a lower prescription for their children because they feel they might be dependent on their glasses.  But research shows that undercorrection may increase myopia progression.

3. Orthokeratology
This type of lenses have show a 30%-50% reduction in the progression of myopia.

4. Vision therapy
Vision therapy, also know as vision training, is used to improve vision skills such as eye movement control, eye focusing and coordination and the team work of the two eyes.  There is no long-term study available to show that vision therapy can slow down the progression of myopia.

5. Atropine
Studies have shown that 1% atropine can slow the progression of myopia by almost 95%.  Atropine knocks out the focusing ability of the child and somehow blocks the signal that results in the elongation of the eye.  However, atropine does have side effects which include loss of accomodation (focusing) and photophobia (sensitivity to light).  Recently, studies have shown that 0.025% or 0.01% used once daily is just as effective as 0.5% atropine.  However, atropine treatment is not used on a regular basis in Canada.

If you are concerned about your child’s progression of myopia, bring your child in for an annual comprehensive eye exam at Avenue Eyecare.

Dr. Sherman Tung, OD FAAO

drtung@avenueeyecare.com
Vancouver Kerrisdale Optometrist

Contact Avenue Eyecare to book your appointment today.

Computer Vision Syndrome

How many hours do you spend on your computer and Iphone?  According to new research, about 60% of parents estimate their children spend up to 4 hours per day at home or in school looking at a digital device’s screen.  Prolonged use of this technology may lead to computer vision syndrome (CVS).  Symptoms include eye strain, headaches, fatigue, burning/tired eyes, loss of focus, blurred vision, double vision, or head/neck pain.  If you are suffering from CVS, here are some guidelines that can help prevent or reduce the symptoms.

1. 20/20/20 rule
When you are using technology for near work for about 20 minutes, take a 20 second break and look at something 20 feet away.  This will help reset your eyes from the locked close-up position.

2. Height and arrangement of the computer
The computer screen should be 15 to 20 degrees below eye level from the center of the screen and should be about 20 to 28 inches away from the eyes.

3. Check for glare
If possible, windows or other light sources should not be directly visible when sitting in front of the monitor.

4. Blinking
To reduce the chances of developing dry eyes, remember to blink.  It helps keep the front surface of the eye moist.  Usually we blink about 15 times a minute.  When we are staring at the monitor, we only blink about 3-5 times a minute.

Dr. Sherman Tung, OD FAAO

drtung@avenueeyecare.com
Vancouver Kerrisdale Optometrist

Contact Avenue Eyecare to book your appointment today.

Halloween Eye Safety Tips

Children will be all dressed up and wandering the streets for candy on Halloween.  Here are some safety tips that will help prevent eye injuries.

1. Avoid costumes that block vision

Masks, wigs and eye patches are fun Halloween accessories but they may block visibility,  especially peripheral/side vision.  A safer option would be using make-up instead.  Hypo-allergenic options are very safe and make sure you keep it away from the eyes.

2. No sharp objects as props

Some pirates and fairy costumes may require a sword or a wand.  Make sure the props are not sharp and remind  your children not to run with anything that can poke their eyes.  Flash lights are also a good idea.  They can illuminate the dark paths and walkways.  A flashlight will also make your child more visible to drivers.

3. Fireworks

Children are at a higher risk of fireworks-related eye injuries.  Make sure you are in an area away from buildings and other overhead obstructions.  We recommend that you wear safety glasses when you are lighting the fireworks.  In addition, don’t let children handle sparklers.  They burn at a very high temperature and can easily cause damage if it comes into contact with the eyes.

4. Decorative Contact Lenses

Most kids nowadays can order spooky cosmetic contact lenses from Clearly Contacts and other online retailers.  Remember that contact lenses are a medical device and requires a valid prescription and fitting by an eyecare professional.  It’s not worth it to be careless with your eyes for one night of fun, only to develop a sight-threatening corneal ulcer the next day.

5. Reflective costumes or stickers

You want your children to be seen, especially when they are crossing the streets.  If their costume is not reflective, come by  Avenue Eyecare to pick up your “Be Seen. Be Safe” stickers.  They are highly reflective 3M stickers and they are FREE!

Dr. Sherman Tung, OD FAAO

drtung@avenueeyecare.com
Vancouver Kerrisdale Optometrist

Contact Avenue Eyecare to book your appointment today.

Night Time Driving Difficulties

The winter months are upon us and daylight savings time is in about 2 weeks.  Several patients are beginning to bring up concerns about difficulty driving at night.  In Vancouver, night driving is even more challenging with the rain, and my patients are having trouble seeing the lines between the roads.  According to National Safety Council, traffic death rates were 3X greater at night compared to day time.

There are many factors that make night driving more difficult.  A comprehensive eye exam  will help determine these causes.

1. Refractive Error: Sometimes a small refractive change in either hyperopia, myopia or astigmatism will make all the difference in the world.  At Avenue Eyecare, we love to trial frame the prescription to see if makes any difference in your distance vision before you purchase your glasses.  It’s like trying on your glasses before you buy them.  It takes away all the guess work on how your glasses will turn out.

2. Media opacity like cataracts:  When driving at night, the pupils are usually enlarged due to your physiological response to darkness.  This allows more light to enter the eye. This is a great thing for normal people.  However, when it comes to people with cataracts, the increased amount of light gets diffracted causing haloes or glare.  If the cataracts are significant enough, a cataract consult would be warranted.

3. Corneal problems: Dry eye disease is a common condition that affects the cornea.  This dryness is exacerbated when the heater is on and may lead to reflex tearing which causes blurred vision.  Other corneal problems may include keratoconus.  Keratoconus is a corneal thinning disease and causes the diffraction of light in random directions.  This causes haloes and glare during night time driving.

4. Retinal problems:  Retinal diseases may be the cause of difficulties with vision in dim lighting.  This may include retinitis pigmentosa (night blindness disease) or macular degeneration (accumulation of waste products in the eye).  Low vision devices may be needed to help you drive.

5. Low quality lenses and coatings:  Lower quality lenses have more distortions and aberrations which cause blurred vision.  Poor quality anti-reflective coatings also tend to peel off and distort vision.  At Avenue Eyecare, if driving is your main priority, we usually recommend Essilor Varilux 360 Lenses with a Crizal Sapphire coating or  Nikon See Max Lenses with a SeeCoat Blue.  Once you try one of the high definition lenses, you’ll appreciate the clarity and brightness of your vision.

Dr. Sherman Tung, OD FAAO

drtung@avenueeyecare.com
Vancouver Kerrisdale Optometrist

Contact Avenue Eyecare to book your appointment today.