Category Archives: Vision

Computer Glasses – What Are They, How Will They Help, Are They Worth it?

Computer glasses are an under used component of a comfortable office environment. As a person approaches their 50’s it becomes more difficult to see things not only at near but at an intermediate range as well. Normal progressive lenses let you see objects clearly at this distance but only by lifting your head up to look through the intermediate portion of the glasses. Using regular glasses while working at the computer leads to neck pain, back pain and eye strain. This is where computer glasses come in.

Progressive lenses allow a person over 40 to view objects clearly at all distances, even computer distance. Progressive lenses let us view intermediate objects by looking half way down the lens. With computer glasses; however, you can view an intermediate object by looking straight ahead (most computer monitors are at eye level), and the bottom of the computer lens lets you focus an object at normal reading distance. Computer glasses allow for a natural eye position so you can comfortably view your computer.

If your computer monitor is at eye level, you are in your late forties or older, and spend more than 30 minutes at the computer a day then computer glasses are definitely a worthwhile investment.

Computer glasses are an important part of making your workstation a comfortable place to work. See this article on visual ergonomics for more information on setting up your workstation.

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Visual Evoked Potential – New Technology Available at Total Eye Care

We have added a new service here at Total Eye Care. It is called the Visual Evoked Potential or VEP. Until recently this technology was only available to large institutions and teach hospitals. We are now able to provide this service for our patients at the Colleyville office.

What is the VEP?

The VEP, or Visual Evoked Potential, measures how well you visual system is working. Testing the integrity of your visual system is done by showing you a series of checkerboard patterns and then measuring the electrical activity between your eye and the visual cortex of your brain.

Your eye converts what you see into very low voltage electrical signals that travel along the optic nerve between your eye and the visual cortex. The computer inside the VEP compares the strength and speed of signal to a database of normal results and then the doctor uses that information to guide his or her diagnosis.

How is the VEP Done?

Two sticky pieces of tape are placed on your forehead and another on the back of your head. A patch is then placed over one eye and you look at a computer monitor that shows you the checkerboard pattern. When the testing is complete the process is reversed for the other eye. That’s all there is to it.

What Does the VEP Tell the Doctor?

The VEP evaluates how well the entire visual system is working. A visual field (peripheral vision test) gives the doctor similar information. In this way the VEP  helps the doctor diagnose and manage patients with glaucoma. The VEP is also used in the diagnosis and treatment of patients with amblyopia, multiple sclerosis, myasthenia gravis, optic atrophy, and concussion to name a few.

My Child Sees Fine – Why Does She Need an Eye Exam

As parents we often think that our son or daughter has good vision and therefore does not need an eye exam.  Common misperceptions of why eye exams in children are not important include, my son doesn’t complain of blurry vision, my child’s grades are good, or the parents have good vision therefore the kids probably do too.

School screening don’t qualify as an eye exam.  While an essential part of protecting the visual and physical health of our children, school screenings were never intended to replace a professional eye exam.  School screenings prevent children from “falling between the cracks” and are best used to supplement regular eye care.  Read more about safeguarding our children’s vision.

Top Ten Reasons to Buy Your Contact Lenses from Your Eye Doctor

1. You are guaranteed to get the correct lenses in the correct parameters

2. You are guaranteed to get unexpired lenses

3. If your lenses are not performing properly you don’t have to worry about exchanging your old lenses

4. You can exchange unopened, unexpired, unmarked boxes in new condition at your yearly eye exam

5. If you have a defective lens, we will replace it free of charge

6. We have the latest manufacturer’s rebates available to save you money

7. Competitive pricing

8. FREE shipping

9. You will be getting the lenses from an authorized distributor of the brand you wear

10. You will have the satisfaction of supporting a local business that cares about you and your eyes

Image courtesy of Flickr user Malkav.

How do 3D Movies Work

3D Glasses, image courtesy of Flicker user Phillip CasablancaThis weekend Taylor and I went with a group of dads and daughters to see A Christmas Carol in 3D.  A popular question was, “so how do they do the 3D effect?”

We can judge depth because our eyes are about 2 1/2 inches apart, allowing each eye to have a slightly different view of an object.  The brain interprets these differing views, allowing us to note that the objects are at varying distances.

In a movie theater, the image is projected onto a flat screen, therefore we must show each eye a slightly different image, this is accomplished by using either polarized lenses (the better method) or red and green lenses (think headache).  Polarized lenses are, by far, the preferred method.  Typically, light radiates in all directions, polarized lenses filter the light so that it radiates in only one direction, with all of the light waves parallel to each other.

The 3D movie glasses use polarized lenses that filter the light 90 degrees apart for each eye, thus allowing each eye to see a different image.  Two movie projectors are then used to show the movie.   Each projector’s image is slightly offset on the screen simulating the distance between our eyes.  While wearing your polarized 3D glasses the movie looks clear and sharp.  If you take your glasses off the movie looks fuzzy with a shadow off to the left.  Your brain will fuse these views giving depth to the image.

An Interesting Experiment

If you take a friend’s 3D movie glasses and hold their left lens in front of your right lens you will see that no light gets through, turn the lenses perpendicular to each other and once again you can see through both lenses.

So How Was The Movie

A Christmas Carol 3D 2009 The last 3D movie I saw used red and green glasses so it was great seeing a 3D movie that did not give me a headache.  The picture looked great and the 3D effects were well done, however that’s about it.  The chase scenes were way to long and really done mostly to show off the movie’s 3d effects.  Jim Carrey was good in his role as Ebenezer Scrooge and the movie stuck to the original book.  So the bottom line, it’s not a bad movie as a matter of fact they did a good job, however the only reason to see this movie, is to see the 3D effects.

Preventing Vision Problems in Children Must Become a Priority in The US

That is the opinion of The National Commission on Vision & Health, in a new report entitled “Building a Comprehensive Vision Care System“, found that 25% of school age children have undiagnosed vision problems and that correcting this must become a national health care priority.

91837233_f94352da20_mSome of the vision problems cited in the literature review included undiagnosed nearsightedness, farsightedness, amblyopia, retinoblastoma, congenital defects, and strabismus.  The report went on to state that a vision screening was not a substitute for an eye exam and that eye exams from an optometrist or ophthalmologist were a very effective way to detect vision problems in children.

In 2004 The Vision council of America estimated that the rate of undetected vision problems in children to be 25%.  The 2010 National Health Objective 28-4 to reduce blindness and visual impairment in children and adolescents has experienced little progress in it’s goal to reduce childhood blindness.

In 2002 the American Public Health Association (APHA) issued a statement supporting regular eye exams in children to improve the detection rate of vision problems instead of regular screenings.  APHA recommended eye exams at age 6 mos, 2 years and 4 years.  A failure of the current screening program is the lack of follow through for children when problems are detected.  “Most forms of vision loss in children are preventable.  Improving the access to eye care for children should be as important as are our current childhood vaccination programs” said Dr. Richard Driscoll.

Sixteen states do not require any vision assessment prior to a child entering school.  The remaining states require some for of vision assessment prior to a child entering school, however only five states require a follow up examination to the screening.  Screenings are clearly not effective if the results are not acted upon.  Only three states, Illinois, Kentucky and Missouri have legislated mandatory eye exams prior to a child entering school.

Cost was found to be an issue with getting visual assessments for children.  Uninsured children did not receive a well child visit 54% of the time.  Often a well child visit includes a visual assessment.

The recommendations of the study to improve access to eye care for children  included funding national campaigns to educate the public regarding the need to seek care for their child, setting up national standards to be adopted by all states, assure adequate vision coverage by all public and private insurers.

For more articles written on The Eye Doc Blog on vision problems in children see

Gene Therapy Restores Vision

Gene Therapy SurgeryScientists at the University of Florida Restore Some Sight to Three Adult Patients with Congenital Vision Loss

One year ago the retina of two men and one woman in their 20s were injected with a harmless virus that contained vision correcting genes.  All three patients lived with severe vision loss from a congenital problem call Leber’s Congenital Amaurosis Type 2.  A gene responsible for a necessary protein used in the visual process is defective, gene therapy fixes the failed gene.  One year after the gene therapy treatment these patients reporting being able to see light which was a significant improvement in their vision.  One of the patients reported that she was able to see her parents clock, she had never been able to do this before.  The study has two more years to run and it is likely that more patients will be added.

This is a very exciting medical development and shows that gene therapy holds great promise.  There are so many genetic conditions, not only in the eye but the entire body, that can benefit from this type of treatment.  Much research still needs to be done, however this lays the groundwork for promising future development. The exciting thing about this discovery is that it shows that it is possible to fix bad genes and improve people’s lives.