vintage phoropter close up

Blue Light

Although research is still early, blue light does affect our eyes and sleep patterns. Please inquire at our office about blue blocking glasses or simply turn down the brightness on all your electronic devices to help preserve your eye health.


For those who like to read the scientific literature directly, here’s a quick tour of some of the latest findings, and a search on blue light and melatonin via the U.S. National Library of Medicine’s PubMed search tool:

  • Room light not only suppresses melatonin production, but it could also impact sleep, thermoregulation, blood pressure and glucose homeostasis
  • Blue light is considered a “carcinogenic pollution” that in mice correlates with higher cancer rates
  • A lack of melatonin is linked to higher rates of breast, ovarian, and prostate cancers, while blocking those blue rays with amber glasses is linked to lower cancer rates
  • Exposure to blue light in people appears to have an impact on mood
  • Lower melatonin in mice is linked with higher rates of depression
  • Too much light exposure can cause retinal toxicity
  • Blue light exposure may be playing a role in the higher incidence of cataracts and macular degeneration seen today


The average dog has 20/75 vision

Did you know?

The average dog has 20/75 vision, meaning a dog sees the same thing at 20 feet than humans with normal vision can see at 75 feet.

The longer a dog’s nose, the greater his field of vision!


Meet Gidget – seeing eye dog in training

If you have been to our clinic, you may have met Gidget (she may have been sleeping under Anita’s desk). Gidget is being trained to be a guide dog for the visually impaired by Dr. Cindy Wagner.

As a guide dog in-training, she has full public access. A requirement of Gidget’s training, by BC Guide Dogs, is that she must always be with someone (so that she gets used to, and always wants to be with her owner). Gidget is still a puppy, so she has a ways to go in her training, but she is doing well. Soon she will be off to “university”. However, if she does not “make the grade” to be a guide dog for someone who is visually impaired, she may still be able to be a support dog for a child with autism.

Gidget was a guest at Dr. Reinders son’s kindergarten class.

Needless to say, she was a hit!

Find out more about guide dogs at


Flying with Colour Blindness

disciplines of flight blog

Though color blindness may not seem interesting to anyone who doesn’t have firsthand experience with it, and reading about it may not feel like a worthwhile investment of time, I discovered a lot of fascinating information as I researched the challenge faced by aviators affected by this condition. And though I personally don’t have first hand experience with color blindness, I do have years of experience with vision problems.

As a young boy at 7 years of age, I failed a school administered vision test, and have worn corrective lenses ever since. Without correction, my eyesight is somewhere around ‘…I think that says STOP…’

Read the complete article from the Disciples of Flight by Anders Clark.


What Is Color Blindness?

The retina, the area of the eye responsible for receiving images from the lens and converting them to an electronic signal for transmission to the brain, is filled with specialized photoreceptor cells called cones and rods. Millions of them. There are roughly 6 million cone cells and 125 million rod cells, to be more precise. So why does the retina need all these specialized cells? Well, the cone cells, located in the center of the retina, come in three varieties: those containing blue sensitive pigment (roughly 2% of the cells), those containing green sensitive pigment (33%), and those containing red sensitive pigment (65%) and primarily help with the perception of color and fine detail. The rods, located around the outer edges of the retina and over 1000 times more sensitive than the cones, are responsible for night vision, perceiving brightness, and distinguishing shapes.

A person who has healthy ‘trichromatic’ vision, with all of the cone cells functioning normally, can identify over 7 million different colors. (What’s the Crayola? Your ultimate collection has 152 colors? WEAK!) Now, in North America*, 8% of the male population, and 0.5%** of the female population have cone cells of one color type that are either malfunctioning (known as anomalous trichromatism), which causes small shifts in color perception; cone cells of one color type that are non-functioning (known as dichromatism), causing large shifts in color perception; or only one type of functioning cone cell (known as monochromatism), which causes the total inability to distinguish color. People afflicted with anomalous trichromatism and dichromatism are classified as having a ‘color vision deficiency’, as they can still distinguish color to one degree or another, and are therefore not actually color blind. The term ‘color blind’ only truly applies to those suffering from monochromatism.

Interestingly, the majority of people who have a color deficiency suffer from anomalous trichromatism of the green cone cells, while people afflicted with monochromatism are the most rare (a more advanced breakdown of the color deficiency percentages can be found at the end of the article.)

OK, so to quickly recap, the majority of people with ‘color blindness’ actually suffer from a color deficiency, and can still distinguish between most colors to a fairly effective degree.


TWECS Eye Care Mission 2013, Philippines: After Typhoon Haiyan


These dispatches were written by Dr. McDougall on a February, 2014 mission to the area of the Philippines devastated by a “Super Typhoon” in November 2013. 

We have arrived safely in Tacloban, and the first impression of the devastation is staggering. Flying in gave a sweeping perspective of the damage from the typhoon: in the outlying areas there are entire hillsides covered in Palm trees that have seen stripped of all of their foliage, with no green at all, just miles and miles of 20-30-foot-tall palm sticks that look like toothpicks that have been stuck into the boggy wet ground. And the as we fly over the city and into the airport, the man-made structures are just torn apart, and strewn all over the place, just like you see in the online pictures. But, as is often the case, photographs don’t do it justice, and in this case in a really bad, bad way.

ship-villagedestructionroofless-house Read More

TWECS Eye Care Mission 2011: Nicaragua, Central America


The following are dispatches sent by Dr. McDougall from a 2011 eye-care mission to Nicaragua. 


Auspicious Arrival

We have arrived safely, and already the promise of adventure has already begun.

Thanks to the work in advance of TWECS founders Marina and Derick, passing through customs with our equipment and donated glasses was an absolute breeze. Everyone was very supportive of us the whole way.

The ride to our camp was not such a breeze. We left the airport at about midnight, and headed for the beach camp which was about a three-hour bumpy ride. Thank God they stocked it with cerveza (beer)!. Halfway through the trip our bus collided with a horse, tearing the whole right front side off the bus! Luckily no one on the bus was hurt, but the horse had been badly injured, and our “host” Gerry (a big 300-pound Nicaraguan that we are already calling Tony Soprano amongst ourselves) had to get out and shoot the horse to put it out of it’s misery (thank goodness). Welcome, and Whoa! I guess its good to know our host is packing heat.

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TWECS Eye Care Mission to Africa, 2009: Ethiopia


The following are dispatches by Dr. McDougall sent from Addis Ababa, Ethiopia, on a November 2009 mission with TWECS (Third World Eye Care Society). 

Greetings from Africa!

November 7, 2009

I can’t believe we made it. It literally was 30 hours door to door, but amazingly I don’t feel too bad. We made it through customs quite easily, and without too much grumbling (as we expected). Our hotel is nice, and we just celebrated arriving with some local beer, and I just had my first bit of gurdga (which is when one of the locals asked me to sample his dinner, then fed it to me by hand!). I had read about that, but didn’t expect it within the first couple hours here!

It already feels like I have been away for weeks. Tomorrow we start to set up our clinic, and tour the city and the barrios before we start. I am with a great group of people, and so far the Ethiopians have been lovely.

So far I am safe, have been hand-fed, and am a bit buzzed on local beer and happy!

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