Sunday, June 22, 2014

How to be visible at night to older drivers

A new study says that it takes longer for older drivers to notice pedestrians at night. And pedestrians are more visible to them if they wear reflective strips on their movable joints like such as shoulders, elbows, wrists, waist, knees and ankle. Eye doctors can test seniors to ensure that they are safe driving at night. Learn more.

Wednesday, June 4, 2014

Eye movement dysfunctions, their treatment and reading related problems in patients with mild traumatic brain injury (mTBI)

We have large vision therapy practice at our Vancouver vision and eye clinic where one category of patients that we treat come to us with traumatic brain injuries that have caused vision problems in the patients, including reading difficulties.  

Reading is a complex task involving a number of functions, abilities and visual skills.  Reading has oculomotor, sensory, cognitive, and attentional components, and all of these must be integrated. If any one of them is affected by a brain injury, they reading is likely to be negatively affected as well.   For example, accurate eye movements are essential for efficient reading. This means that if a traumatic brain injury (TBI) has affected the normal control of eye movements, then reading will likely be adversely impacted.

How can doctors fix these problems?  That was the issue investigated by the authors of a study published in 2007 in the Journal of Behavioral Optometry.  The researchers looked at three studies done by their research group which involved versional oculomotor dysfunctions, their related reading problems, and treatment in a group of patients with mild TBI whose injury affected their vision and reading ability.

Let's take a second to make sure we understand a few of those scientific terms.  A "version" is an eye movement involving both eyes moving together as a team in the same direction.  A "versional oculomotor dysfunction" is a problem in the way the eyes move together as a team.

The results have shown that in a large clinical sample (160 patients), approximately 90% had one or more oculomotor deficits, such as convergence insufficiency or abnormal saccadic tracking- a saccade is a fast movement of the eye like the moments the eye does when tracking words on a printed page.  Deficits in these areas have the potential to interfere with reading performance.  

Out of the 160 patients examined, thirty-three of them completed a program of vision therapy. Of the patients who received vision therapy, an impressive ninety percent of them experienced improvement in at least one related sign and one related symptom. 

The researchers also laboratory-tested 9 of the study subjects who had  eye-movement-related reading problems and found that all of them improved their overall reading performance and versional eye tracking ability after vision therapy.

There are a number of conclusions to draw from this study:
  1. eye movement dysfunctions are common in individuals with mild TBI;
  2. vision therapy can effectively treat eye movement dysfunctions;
  3. the positive vision therapy findings demonstrate that the adult brain can be changed and molded (re-wired) with vision therapy and this shows the presence of considerable neuroplasticity in adults with mild traumatic brain injury;
  4. optometric vision therapy should be used to treat  visually symptomatic patients with TBI who have eye-movement-based reading problems.

More information

To learn more about vision therapy and brain injuries, visit:
Another excellent resource is the website of NORA, the Neuro-Optometric Rehabilitation Association.


Related Articles
Traumatic brain injury often results in convergence insufficiency 
Dec 11, 2012

Brain injuries and vision problems
Nov 04, 2012

Eye movement dysfunctions, their treatment and reading relateed problems in patients with traumatic brain injury
Dec 28, 2012

Vision problems after car accident are caused by brain injury 
Nov 07, 2012

- See more at:

Image courtesy of Victor Habbick /

Monday, June 2, 2014

Binocular vision and older adults

Binocular vision, refers to the way that the two eyes work together as a team.  Deficiencies in this ability  is one of the major categories of vision disorder that is effectively treated with vision therapy. Recent research has sought to determine the prevalence of binocular vision disorders in adults aged 60 or over and has found that the prevalence of binocular vision disorders increases as we age.

The results of a study from researchers at Canada's University of Waterloo found that as many as 27% of adults in their sixties have a binocular vision or eye movement disorder and 38% of adults over the age of 80 have such a vision disorder. That's compared to the general population in which 20% of people have a binocular vision disorder.

Binocular vision disorders can cause problems in reading, driving, motion sickness and depth perception. The latter problem is of particular concern among the elderly, as people with reduced depth perception are at greater risk of falls.

According to the press release issued by the University of Waterloo to publicize the results of the study, vision therapy and eye-glasses are effective treatments for binocular vision disorders:

Although the study suggests that the rate of binocular vision disorders in older adults is higher than expected, there is good news. Many binocular vision disorders are treatable with glasses, vision therapy, or in some cases surgery. 
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January 23, 2014

Sunday, June 1, 2014

Demodex mites in eyelashes - treatment in Vancouver

What is demodex?

Demodex is an eight-legged mite that lives in hair folicles and sebaceous glands. Some species of demodex commonly infect humans. You can catch demodex through contact with the mite or from or dust containing eggs.

Demodex and dry, irritated eyes

The two types of Demodex that infect humans are D. brevis and D. folliculorum.  D. brevis is about 0.2 mm long and tends to live inside the eye lash’s sebaceous glands and in meibomian glands. Meibomian glands are critical for proper tear production and when these glands don't work properly, dry eye disease often results. That's why D. brevis can be associated with meibomian gland disease and deficient tear quality.  

D. folliculorum buries itself face down near the root of the eyelash and it is associated with anterior blepharitis, which is inflamed, irritated and itchy eyelids.

Treatment options for demodex infestation

There are a number of options for treating demodex infestation.  One of the most effective treatments that we use in our Vancouver optometry clinic involves a series of in-office procedures involving the use of anesthetic, tea tree oil, antibiotics and topical steroids.

If I have demodex, what about the rest of my family?

Doctors frequently observe that if one family member has an infestation, other family members are frequently also infected due to close contact.  It is a good idea to make appointments for family members if you are diagnosed with a demodex infection.