Driving at night – What should I know?

Courtesy of Johnathon, Flickr Creative Commons

Courtesy of Johnathon, Flickr Creative Commons

One of the most common questions patients ask is how to improve their night vision. In fact, many elderly patients have given up night driving all together.

So, what is it about night driving that makes it so hard? Well certainly, our visual abilities are dependent on light. With reduced lighting comes a variety of limiting factors like reduced visual acuity, poor color vision, decreased depth perception, and impaired peripheral vision. All of these factors combine to make accidents 3x more likely at night.

So, how do we reduce our chances of an accident?

1) It is imperative that your vision is corrected to its maximum potential. A complete eye examination will not only check the best prescription for you – it can also detect potential problems that affect night vision like dry eye, cataracts and macular degeneration, all of which occur with greater frequency with age. Additionally, if you are prescribed glasses at your visit, make sure to obtain lenses with an anti-reflective coating. This coating will reduce glare dramatically and has been shown to improve reaction time.

2) Make sure your windows and headlights are perfectly clean. Every time I clean my windows at a gas station I wonder why I didn’t do it earlier. This advice goes for your glasses too. Even a perfect prescription can be worthless if your glasses are dirty or scratched.

3) Finally, it is important to know your limits. If you have real concerns about night driving there is nothing wrong with asking for a ride, catching a cab or public transportation or just ordering in. Until next time, be safe on the road!

 ~Dr. David Ardaya, OD
California Optometric Association
http://eyehelp.org
http://www.coavision.org

Advertisements

You may have cataracts?

Courtesy of entirelysubjective on Flickr

Courtesy of entirelysubjective on Flickr

Cataracts are common

Not a day goes by in the office when I don’t tell a patient that he or she has a cataract, which is any kind of clouding in the crystalline lens of our eye. Some patients have heard of the term and understand that it’s a common occurrence as one ages. Other patients are terrified of the term and think it’s a disease that will make them blind. But the patients I relate to are the ones who hear the word cataract, and think “I’m old.”

Cataracts can affect your vision

If it helps, most cataracts develop over decades, from young adulthood onward. As early as 40 years old, we can start to notice the effects of this change over time. The crystalline lens in our eye, which is responsible for focusing light onto our retinas, begins to change shape and chemical structure over time. These changes result in more light scatter and dimming of vision. Usually, a patient will begin noticing glare from car headlights, double or ghost images around letters and lights or that night vision is not as clear or bright.

These are often initial symptoms and do not require treatment. As the cataracts continue to develop, patients’ eyeglass prescriptions may begin to change and they will also experience blurry or cloudy vision with worsening of the above symptoms. When they reach this point, which is about half of patients over the age of 65, cataract surgery may be indicated.

Cataract surgery – not as bad as you’d think

Cataract surgery is the most common surgery performed in the world. Nowadays, it can be a 15 minute out-patient procedure. The cataract is removed from the eye and replaced with an artificial lens implant, called an intraocular lens. With many advancements in this field, the lens implant can also have specialty optics which can correct for astigmatism or for both distance and reading.

What many don’t know is that cataract surgery is an optional procedure. A cataract is not malignant and does not always have to be removed. However, a patient’s vision will improve significantly with a successful cataract surgery. They will notice a much brighter and clearer environment. Some patients who have glaucoma or have a crowding of the internal structures of the eye would benefit from having cataract surgery.

Image

Photo courtesy of Community Eye Health on Flickr

Types of cataracts

There are many different forms of cataracts. In fact, I found a cataract in a 9-month old baby when his mom brought him in for a well-visit eye examination. In such a case where the eye is still developing, clouding of the lens can interfere with visual development and needs to be removed. Other congenital form of cataracts may simply be a cloudy spot on the lens which doesn’t interfere with vision. In this case, there is no need for cataract surgery.

Cataracts can also develop from trauma, use of certain medications and diabetes. Depending on the type, a cataract can slowly worsen over years, or change rapidly requiring surgical intervention within months. For patients whose vision is changing rapidly, I often like to follow them every few months to monitor for vision and cataract changes.

People often ask what can be done to prevent cataracts. Unfortunately, genetics plays a factor so if your parents required cataract surgery, you will most likely need one also. If you’re outdoors, wear a good quality pair of sunglasses that block UVA/UVB rays. This goes for kids as well since exposure to ultraviolet radiation is cumulative. If you’re outdoors for long periods of time, throw on a hat for added protection. Smoking has been shown to cause cataracts also, so limit your exposure to cigarette smoke. If you are currently being treated for diabetes or using steroid medications, be sure to see your internist regularly.

Why wait for your vision to blur? See your optometrist every year!

Most importantly, see your optometrist annually for an eye examination. They can check for cataracts but also determine if there are other factors that may be contributing to a reduction in your vision. It’s not just the lens that helps you to see but a whole network of related structures that work as a team to provide you with optimal vision.  If you require a new pair of glasses, always opt for an anti-glare coat on the lenses, which would further reduce disabling glare symptoms.

~Cindy P. Wang, OD, FAAO
http://eyehelp.org
http://www.coavision.org

 

What did my doctor just say? Common terms your eye doctor will use and what they mean

Courtesy of riekhavoc (caughtup?) on Flickr

Courtesy of riekhavoc (caughtup?) on Flickr

Have you ever felt like you were not quite sure what just happened at your optometrist’s office? It is difficult enough to answer the “which is better, one or two?” questions and then at the end of the exam to try and understand the doctor’s explanations with difficult optometry terms without secretly worrying that you might have said something wrong!

Hopefully this blog will help you better understand some of the more common terms we use in our examinations.

1) First of all, most comprehensive exams will include a detailed case history. The doctor will want to know your family medical and ocular (eye) history. Some terms you may hear include the most common eye diseases – cataracts, glaucoma and macular degeneration.

  • Cataract is the term used when the natural lens of your eye becomes cloudy, causing blurred and distorted vision.
  • Glaucoma is the eye disease that causes your eye to have excessively high pressure, which can lead to long-term damage of the nerve in the eye.
  • Macular degeneration is a disease that affects your central or straight ahead vision.

Not only will the optometrist ask you about a family history of any of these conditions, they will also assess your eye health and your possible risk for developing any of them.

2) Next, the optometrist will perform a refraction to get you the best possible glasses or contacts that will correct your vision.

  • A refraction is just the process of determining for each individual what are the best lenses to give you maximum visual clarity and comfort at both distance and near.
  • Myopia – nearsightedness or the ability to see better at near than at far.
  • Hyperopia or farsightedness, really means that it is more difficult to focus at near and at far distances.
  • Astigmatism: this refers to the shape of the front surface of the eye being more football shaped rather than basketball shaped.

3) There are a few terms you might hear specifically in an child’s exam.

  • Pursuits: slow, smooth eye tracking.
  • Saccades: fast reading eye tracking.
  • Accommodation: focusing.
  • Binocularity: the ability of the eyes to work together as a team.

4) Finally, there are some terms regarding glasses that it might help to define.

  • Progressive lenses are the kind of “no line bifocal” that you might hear about on TV. But, unlike a bifocal, where there are two areas of vision, near and far, progressives have an unlimited amount of areas as you look from distance to near in the lens.
  • Transition lenses are the kind that change to dark outside. They undergo an anti-reflective treatment, which eliminates all glare and allows for crisper vision, especially at night.

Hopefully, this quick explanation helps with some of the confusing terms in an eye exam. As for any others, always ask your optometrist to explain something that does not make sense.

~Lisa Weiss, OD, MEd, FCOVD
California Optometric Association
http://www.coavision.org

The ABCs of cataracts

CataractCataracts are a fact of life. Anyone who lives long enough will get them and almost everyone knows someone who has had them.  The good news is, with the latest technology available, improving your vision is very safe and will often times leave you with better vision without glasses than you had before the cataract.

Let’s look at the ABCs of cataracts:

A – Age. Remember that cataracts are changes to the lens of our eye as we get older. Different factors can influence when the cataracts start to form. Cataracts tend to develop sooner in folks who spend a lot of time outdoors in the sun without sun protection or sunglasses. They also tend to form earlier if you have diabetes or if you are a smoker. So keeping your eyes out of the sun and staying healthy will help delay the onset.

B – Blurry Vision. The lens of the eye starts changing with cataract formation, making vision blurry. It is like looking out of a blurry window. Usually night driving will be much harder and cataracts can cause difficulty with headlights a night. Cataracts can also cause glasses prescriptions to change as well. It is common to need one or two changes in glasses prescription before the cataract is affecting vision enough to have it removed.

Courtesy of laulau555 on Flickr

Courtesy of laulau555 on Flickr

C – Cure! The good news about this eye disease is that there is a very good treatment option. Cataract surgery involves removing the blurry lens from the eye and inserting a prosthetic lens in its place. This is an outpatient procedure and can take as little as 20 minutes.  The new lens often has a prescription in it that will be very close to your current glasses or contact lens prescription and will allow you to see better without the use of glasses or contacts.  There are even lenses available that can help with near vision as well as far vision. Usually after cataract surgery, vision improvement can be noticed as early as the next day.

Remember, make sure to have routine eye health and vision exams to determine if cataracts are forming or changing.  Your eye care provider can assist you in determining the appropriate time to have them removed.  Until then, stay healthy and wear sunglasses!

~Lisa M. Weiss, OD, FCOVD
California Optometric Association
http://www.coavision.org

Vision and the aging eye

Courtesy of ORBIS US on Flickr

Courtesy of ORBIS US on Flickr

Many patients reach a certain life stage and realize they need to start thinking more about their vision and preventing eye problems.  This usually happens in their early to mid-forties when people notice reading is a lot easier when there’s plenty of light and the print is held further away.  Those who have seen an eye care provider for this problem should have already discovered that this is a normal aging process.  But how does one know when vision changes are normal or should be concerning?

Eye conditions that impact vision:

  • Presbyopia is the medical term for when the focusing muscles in the eye are not as flexible, causing poor focusing ability for objects nearby.  This typically occurs in the late thirties/early forties and is easily corrected with reading glasses or bifocal or progressive lenses.
  • Cataracts begin to develop in our forties and progress over time.  There is a natural clear crystalline lens in our eye which focuses light onto our retina.  With ultraviolet ray exposure, this lens can become more opaque and yellow over time, causing a dimming of vision and glare and haloes around lights.  The best way to prevent cataracts from progressing quickly is to protect the eyes with UV-blocking sunglasses anytime you are outdoors.  The good news about cataracts is that they can be easily removed and replaced with an artificial lens implant.  With the latest technology of intraocular lens implants such as muiltifocal lenses, patients are now able to see clearly at all distances without the use of glasses or reading glasses.
  • Glaucoma is a symptomless eye disease of the optic nerve head where the nerve slowly deteriorates over time.  Most patients who develop glaucoma will not have any symptoms until the late stages of the disease, when peripheral vision deteriorates and patients are left with tunnel vision.  There is no cure or preventative measure for glaucoma, however, it is easily treated with eyedrops.  The only way to determine if you have glaucoma is to have annual comprehensive eye examinations.

    Courtesy of Nargopolis on Flickr

    Courtesy of Nargopolis on Flickr

  • Macular Degeneration is another common eye disease that can cause debilitating vision loss.  This occurs when the macular region of the retina loses its integrity causing poor central vision with distortion or gray spots.  It is often detected upon routine examination, especially when photos of the retina are compared over time.  Fortunately, there have been extensive studies on macular degeneration and the field has changed dramatically over the last several years.  An important test in recent years is genetic testing to determine one’s risk factor for vision loss as a result of macular degeneration, as well as antioxidants that may be useful in reducing this risk.  Clear risk factors include a history of smoking, exposure to ultraviolet radiation, increased cholesterol levels and Caucasian women with lighter eyes and fairer complexions.
  • Retinal Detachment tends to occur more often in those who are older than 65.  The retina is a thin and fragile tissue that lines the back wall of the eye and sends visual information to the brain.  This tissue becomes more fragile over time and can easily develop a hole or tear leading to a retinal detachment.  If you experience flashes of light, new floaters, or a change in your vision, you need to be seen right away by your eyecare provider.

There are a myriad of eye conditions that can develop as one ages.  The most important and useful method of preventing vision loss is to stay healthy.  See your primary care physician regularly to evaluate and treat high blood pressure, high cholesterol, diabetes and other health conditions.  If you have uncontrolled health conditions, you can easily lose your vision to diabetic retinopathy, hypertensive retinopathy, or a stroke in the eye.

So, as I tell all my patients, see your physician regularly, eat green leafy vegetables, take your medications, and monitor your own blood pressure or blood sugar.  And of course, wear sunglasses outdoors and see your optometrist annually.

~Cindy P. Wang, OD, FAAO
California Optometric Association
http://www.coavision.org