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Questions & Answers on Colour Blindness with Dr. Leong

Are You Colour Blind?

Dr. Leong, answers some popular questions about colour blindness (AKA colour vision deficiency):
1. Why can’t I see colours at night?
There are 2 types of photoreceptors – rods and cones. Cones see colour, but they are not stimulated when it is too dark. Rods help you see at night, but they do not see colour. Green is the easiest colour to see when it is dark.
2. True or false: Colour blind people cannot tell the difference between red and green lights on traffic signals.
False. People with red-green colour blindness confuse some colours, but can discriminate many colours. They just see colours differently from the norm.
3. True or false: Colour blindness is more common in males
True. Colour deficiency is in 7% of males, usually genetically passed from the mother’s side of the family as the gene is on the X chromosome.
4. Did you know… colour deficiency can be acquired?
Example 1. Alcoholics lose some colour vision from insufficiency Vitamin B12. Reds will appear darker and less saturated.
Example 2. Viagra – a side effect of taking this medication is that colours may have a bluish tinge.
Did you know? Your Calgary AB eye doctors at Foresight Eyecare will even check for signs of cataracts as part of your comprehensive eye exam!

Thank you for trusting your eyecare with us over the years.  The Foresight Eyecare team follows the government mandate to reduce the spread of the COVID-19 pandemic.  After December 2020 announcements made by the Alberta Government, our clinic is following the revised Infection Prevention and Control policy by the Alberta College of Optometrists.

Patients interested in obtaining eye exam services or eye care products can be seen by appointment only.  Please call ahead, and staff will arrange an appointment time and ask COVID-19 screening questions.  If you have any symptoms of cough, fever, runny nose or shortness of breath, we ask that you call or e-mail us and do not attend the clinic for your scheduled visit.   Within the clinic, please wear a mask and use the hand sanitizer at reception.  Our clinic complies with the City of Calgary bylaw requiring mask covering over the age of two years old.  For patients who are unable to wear a face covering due to medical reasons, the patient can be scheduled for an appointment at a time when minimal number of other patients are in the clinic such as at the beginning or end of the day to ensure appropriate physical distancing requirements.

We are using disposable disinfectant wipes on all surfaces and devices such as front desk counters, chairs, handles in exam rooms and waiting room.  All eyewear that have been touched by patients are continually being sanitized.   Any toys and magazines are stored at this time.  Examination areas are being sanitized with hospital grade disinfectant.  Debit and credit cards but NO CASH payments will be accepted.

COVID-19 symptoms are not always obvious.  We want to fend off this pandemic and minimize risk to our patients and the Foresight staff as front line health workers.   Contact that is closer than 2 m (6 feet) is to be avoided, with barriers in place when this cannot be avoided. We choose to continue to do our work and cautiously take care of our patients with compassion, humility, gentleness, and patience.   It is a challenging and new experience for many of us, so let‘s support each other and prevent virus spread!  Beyond 2020, our focus is on take care of you and keeping Clean Hands, Clear Heads and Open Hearts.   For more information, please refer to the following web pages or phone Health Link 811.

Drs. Dianna Leong, Anh Bui, Andrew Chan