Evaluating Treatment Claims

9/03/14

The following article on evaluating treatment claims is from the Science-Based Medicine blog is being used with their permission. Since Discovery Eye Foundation provided the inspiration for Dr. Hall, we thought you might enjoy it as well.

I recently wrote about the claim that acupuncture can improve vision in patients with macular degeneration. In response, I received this e-mail:

“At Discovery Eye Foundation we have an education and outreach program for people with age-related macular degeneration, the Macular Degeneration Partnership. We are constantly getting calls from people who have heard of a new “cure” or a way to stop their vision loss. It is always hard to interject reality into the conversation and hear the hope leave their voice, replaced by frustration or despair.”

The e-mail suggested I write an article providing guidelines for consumers to help them evaluate the validity of treatment claims for themselves. On SBM we are constantly stressing the need to apply critical thinking to what you read, and the many pitfalls to be avoided. I’ll try to synthesize some of the principles into a handy list of questions.

What kind of evidence is there?

• If the claim is based on nothing but testimonials, STOP RIGHT THERE. You can forget about it, or at least file it away until there is better evidence. Anecdotes are not evidence; they only serve to suggest promising avenues of research. Science is the only reliable way to determine if a treatment is safe and effective.

• Is the claim based on a gold standard randomized, placebo-controlled, peer-reviewed study or some lesser kind of evidence like case reports? Was it published in a reputable mainstream medical journal? (If you’re not sure how reputable the journal is, you can look it up on tables of “journal impact factors.”

• Keep in mind that half of all studies are wrong. There are many factors that can lead to error. Preliminary or pilot studies that are positive are frequently followed by better, larger studies that are negative. We can never rely on one study without confirmation.

• Was it a meaningful clinical study in humans?

In vitrolab studies and animal studies may not be applicable to humans; if promising, they must be confirmed in good human studies. If it was a human study, did it show meaningful outcomes that made a real difference, like a reduction in heart attacks, or did it just show an improvement in lab values or risk factors?

• Were there 10 subjects or 300? Large studies are more trustworthy than small ones. The fewer dropouts, the better.

• Did it use an appropriate placebo control that subjects really couldn’t distinguish from the active treatment?

• Have other studies found similar results? Are there any studies that show the opposite? You can search PubMed and look for them.

Who is making the claim?

Is it someone who is likely to be biased?
Is it someone who provides the treatment or sells the product?
Is it someone with expert medical knowledge or someone like the schoolteacher who claimed she had invented a cure for the common cold?
Does the person have a good reputation, or a track record of making questionable statements?
Is it someone who quotes or associates with unreliable sources like Mercola.com, the Weston Price Foundation, or the Health Ranger? Quackwatch has a useful list of non-recommended sources of health advice.

Where was the claim reported?

Real medical breakthroughs would be headline news. It’s not likely you would first hear about a cure for diabetes on an afternoon talk show or a Facebook page. Has your doctor heard of it? Are mainstream doctors recommending it? Is it covered on professional medical websites like the American Academy of Pediatrics or disease-focused websites like the American Diabetes Association? Is it sold only through multilevel marketing schemes?

What kind of language is being used?

Is it a sober factual report with caveats, or is it full of hype and buzzwords like “miracle,” “natural,” “known to the ancients,” “quantum,” “amazing,” “revolutionary”? If it really worked, advertising gimmicks wouldn’t be needed to sell it.

Does Gwyneth Paltrow swear it worked for her?

Testimonials can be very passionate but they are notoriously unreliable. Getting better when you use a treatment doesn’t necessarily mean you got better because of the treatment. Symptoms can fluctuate, diseases can resolve without treatment, and placebos can fool people. Perceptions can be wrong (think of optical illusions), the meaning of true perceptions can be misinterpreted, and memories can be inaccurate. Every snake oil salesman has reams of testimonials, and through the centuries there were testimonials galore for bloodletting to balance the humors. People frequently come to believe bogus remedies have worked for them. Barry Beyerstein wrote a classic article about that; it’s essential reading.

Does it make sense?

Is there a plausible mechanism of action? If someone claimed that standing on your head and whistling Dixie would cure diabetes, I think you would be skeptical. If it claims to work by a mechanism incompatible with known scientific principles, the level of evidence would have to be extraordinary for it to outweigh all the evidence those scientific principles are based on. Homeopathy’s claim that water can cure by remembering long-gone molecules, even after the water has been dripped onto a sugar pill and allowed to evaporate, would require extraordinary evidence indeed. If it’s a new antibiotic that is related to an old one, an ordinary level of evidence would suffice.

Is there a double standard?

Are they asking you to accept a “natural” or “alternative” treatment on the basis of the kind of evidence that you wouldn’t want the FDA to accept for allowing marketing of a prescription drug? There is only one science and only one standard of evidence.

Does it sound too good to be true?

Then it probably is too good to be true. Does it promise to cure a hitherto-incurable disease? Does it promise you can eat all you want and still lose weight? Does it promise there are no side effects of any kind? Does it remind you of the spiel of a used car salesman or a TV infomercial? Caveat emptor.

Who disagrees and why?

This is the most important question you can ask. It is rare for 100% of people to agree on anything. If you can find someone who disagrees, you can examine the reasons given for both opinions, and it will usually become obvious which side makes more sense. If you can’t find anyone who disagrees, it might be because it’s too new or because no scientist has taken it seriously enough to bother writing about it. In that case, withhold judgment and keep checking until someone does disagree.

Hope springs eternal, but true hope is better than false hope

If you are a desperate patient, it’s only natural to grasp at any straw of hope; but when the evidence is insufficient, the reasonable approach is to withhold judgment and wait for better evidence. You might think, “If it works, I don’t want to wait” but history teaches us that the great majority of these things don’t pan out. It might not do any harm, but then again it might; there might be adverse effects that haven’t been identified yet, it might raise false hopes only to dash them, and if nothing else it might waste time and money or interfere with getting more appropriate care. When you take an inadequately-tested medicine, you are essentially offering yourself as a guinea pig in a haphazard uncontrolled experiment that doesn’t even keep records. Of course, that’s your privilege; but I hope you would do it with your eyes open, with a realistic understanding of the state of the evidence.

Harriet A. Hall, MD
Retired US Air Force Physician
Editor of Science-Based Medicine Blog
Author of SkepDoc column in Skeptic Magazine

Telemedicine For Diagnosing Retinopathy Of Prematurity

8/28/14

Technology now allows patients access to highly-qualified, specialized care, no matter where they live. This potential is demonstrated in the sight-saving treatments that can be used to help children lead normal healthy lives. The following article is posted with the permission of the National Institute of Health (NIH).

Telemedicine is an effective strategy to screen for the potentially blinding disease known as retinopathy of prematurity, according to a study funded by the National Eye Institute (NEI). The investigators say that the approach, if adopted broadly, could help ease the strain on hospitals with limited access to ophthalmologists and lead to better care for infants in underserved areas of the country. NEI is a part of the National Institutes of Health.

The telemedicine strategy consisted of electronically sending photos of babies’ eyes to a distant image reading center for evaluation. Staff at the image reading center, who were trained to recognize signs of severe ROP, identified whether infants should be referred to an ophthalmologist for evaluation and potential treatment. The study tested how accurately the telemedicine approach reproduced the conclusions of ophthalmologists who examined the babies onsite.

“This study provides validation for a telemedicine approach to ROP screening and could help save thousands of infants from going blind,” said Graham E. Quinn, MD, professor of ophthalmology at the Children’s Hospital of Philadelphia and the lead investigator for the study, which is reported today in JAMA Ophthalmology. The study was conducted by the e-ROP Cooperative Group, a collaboration that includes 12 clinics in the United States and one in Canada.

Some degree of ROP appears in more than half of all infants born at 30 weeks pregnancy or younger — a full-term pregnancy is 40 weeks — but only about 5 to 8 percent of cases become severe enough to require treatment. In ROP, blood vessels in the tissue in the back of the eye called the retina begin to grow abnormally, which can lead to scarring and detachment of the retina. Treatment involves destroying the abnormal blood vessels with lasers or freezing them using a technique called cryoablation. Early diagnosis and prompt treatment is the best prevention for vision loss from ROP, which is why the American Academy of Ophthalmology recommends routine screening for all babies who are born at gestational age 30 weeks or younger or who weigh less than 3.3 pounds at birth.

The study evaluated telemedicine for ROP screening during the usual care of 1,257 premature infants who were born, on average, 13 weeks early. About every nine days, each infant underwent screening by an ophthalmologist, who assessed whether referral for treatment was warranted. Those who were referred were designated as having referral-warranted ROP (RW-ROP). Either immediately before or after the exam, a non-physician staff member in the neonatal intensive care unit (NICU) took images of the infant’s retinas and uploaded them to a secure server at the University of Oklahoma, Oklahoma City. Trained non-physician image readers at the University of Pennsylvania, Philadelphia, then downloaded the photos, independently evaluated them following a standard protocol, and reported the presence or absence of RW-ROP.

Through the telemedicine approach, non-physician image readers correctly identified 90 percent of the infants deemed to have RW-ROP based on examination by an ophthalmologist. And they were correct 87 percent of the time when presented with images from infants who lacked RW-ROP. The examining ophthalmologists documented 244 infants with RW-ROP on exam. After referral, 162 infants were treated. Of these, non-physician image readers identified RW-ROP in all but three infants (98 percent). “This is the first large clinical investigation of telemedicine to test the ability of non-physicians to recognize ROP at high risk of causing vision loss,” said Eleanor Schron, Ph.D., group leader of NEI Clinical Applications. “The results suggest that telemedicine could improve detection and treatment of ROP for millions of at-risk babies worldwide who lack immediate in-person access to an ophthalmologist,” she said.

About 450,000 (12 percent) of the 3.9 million babies born each year in the United States are premature. The number of preterm infants who survive has surged in middle income countries in Latin America, Asia, and Eastern Europe. In these parts of the world, rates of childhood blindness from ROP are estimated at 15 to 30 percent — compared to 13 percent in the United States.

One advantage of telemedicine ROP screening is that it can be done more frequently than screening by an ophthalmologist. “It’s much easier to examine the retina when not dealing with a wiggling baby,” said Dr. Quinn. “If a baby is too fussy or otherwise unavailable when the ophthalmologist visits the NICU, the exam may be delayed until the ophthalmologist returns — sometimes up to a week later.”

Weekly ROP screening — or even more frequently for high-risk babies — is a realistic goal for telemedicine and could help catch all cases needing treatment, according to the report. In the study, imaging was restricted to occasions when an ophthalmologist examined the baby. In practice, hospital staff could implement an imaging schedule based on the baby’s weight, age at birth, and other risk factors. “With telemedicine, NICU staff can take photos at the convenience of the baby,” said Dr. Quinn.

Telemedicine for evaluating ROP offers several other advantages.

Telemedicine may help detect RW-ROP earlier. In the study, about 43 percent of advanced ROP cases were identified by telemedicine before they were detected by an ophthalmologist — on average, about 15 days earlier.

Telemedicine could save babies and their families the hardship and hazards of being unnecessarily transferred to larger nurseries with greater resources and more on-site ophthalmologists. “Telemedicine potentially gives every hospital access to excellent ROP screening,” Dr. Quinn said.

Telemedicine might also bring down the costs of routine ROP screening by reducing the demands on ophthalmologists, whose time is better allocated to babies who need their attention and expertise. In a separate analysis, the study found that non-physicians and physicians had similar success in assessing photos for RW-ROP. Three physicians evaluated image sets from a random sample of 200 babies (100 with RW-ROP based on the eye exam findings; 100 without) using the standard grading protocol. On average, the physicians correctly identified about 86 percent of RW-ROP cases; the non-physicians were correct 91 percent of the time. The physicians correctly identified about 57 percent of babies without RW-ROP; non-physicians were correct 73 percent of the time.

The cost of establishing a telemedicine ROP screening program includes acquisition of a special camera for taking pictures of the retina, training of NICU personnel to take and transmit quality photos, and establishment and maintenance of an image reading center. “As we move along this road, advances in imaging and grading of images may streamline the process even more,” Dr. Quinn said.

The e-ROP Cooperative Group includes the following clinical sites and resource centers:

Children’s Hospital of Philadelphia
Johns Hopkins University, Baltimore
Boston Children’s Hospital
Nationwide Children’s Hospital and Ohio State University Hospital, Columbus
Duke University (cost-effectiveness center), Durham, North Carolina
University of Louisville, Kentucky
University of Minnesota, Minneapolis
University of Oklahoma (Inoveon ROP Data Center), Oklahoma City
University of Texas Health Science Center at San Antonio
University of Utah, Salt Lake City
Vanderbilt University, Nashville, Tennessee
Hospital of the Foothills Medical Center, Calgary, Alberta
University of Pennsylvania (data coordinating center and image reading center), Philadelphia

For more information about ROP.

Click to view a video about e-ROP.

National Institutes of Health
9000 Rockville Pike
Bethesda, Maryland 20892
301-496-4000,
TTY 301-402-9612

Common Pediatric Eye Diseases

8/21/14

In the third of this series, Buddy Russell, from the Emory University Eye Center, provides a great overview of common pediatric eye diseases.

Some Conditions Frequently Seen in Pediatrics

A basic understanding of some of the conditions that may be present in pediatric patients is important to not only know what they are but also understand well enough to explain to the parent or caregiver. The following is intended to be an overview of some of those conditions and not a complete explanation.

Nystagmus – Nystagmus is a vision condition in which the eyes make repetitive, uncontrolled movements, often resulting in reduced vision. These involuntary eye movements can occur from side to side, up and down, or in a circular pattern. As a result, both eyes are unable to hold steady on objects being viewed. Unusual head positions and head nodding in an attempt to compensate for the condition may accompany nystagmus. Most individuals with nystagmus can reduce the severity of their uncontrolled eye movements and improve vision by positioning their eyes to look to one side. This is called the “null point” where the least amount of nystagmus is evident. To accomplish this they may need to adopt a specific head posture to make the best use of their vision. The direction of nystagmus is defined by the direction of its quick phase (e.g. a right-beating nystagmus is characterized by a rightward-moving quick phase, and a left-beating nystagmus by a leftward-moving quick phase). The oscillations may occur in the vertical, horizontal or torsional planes, or in any combination. The resulting nystagmus is often named as a gross description of the movement, e.g. downbeat nystagmus, upbeat nystagmus, seesaw nystagmus, periodic alternating nystagmus. Having nystagmus affects both vision and self-concept. Most people with nystagmus have some sort of vision limitations because the eyes continually sweep over what they are viewing, making it impossible to obtain a clear image. If a refractive error is found, contact lenses may be the most effective way of obtaining best-corrected vision.
Strabismus – Strabismus is any misalignment of the eyes. It is estimated that 4% of the U.S. population has strabismus. Strabismus is most commonly described by the direction of the eye misalignment. Common types of strabismus are esotropia (turn in), exotropia (turn out), hypotropia (turn down), and hypertropia (turn up). Eye misalignment can cause amblyopia in children. When the eyes are oriented in different directions, the brain receives two different visual images. The brain will ignore the image from the misaligned eye to avoid double vision, resulting in poor vision development of that eye. Also, an eye that sees poorly tends to be misaligned. The goal of strabismus treatment is to improve eye alignment, which allows for better work together (binocular vision). Treatment may involve eyeglasses, contact lenses, eye exercises, prism, and / or eye muscle surgery.
Amblyopia – Amblyopia, sometimes called a “lazy eye,” occurs when one or both eyes do not develop normal vision during early childhood. Babies are not born with 20/20 vision in each eye but must develop it between birth and 6-9 years of age by using each eye regularly with an identical focused image falling on the retina of each eye. If this does not occur in one or both eyes, vision will not develop properly. Instead, vision will be reduced and the affected eye(s) are said to be amblyopic. This common condition, affecting up to 4% of all children, should be diagnosed and treated during infancy or early childhood to obtain optimum three-dimensional vision and to prevent permanent vision loss. What causes amblyopia?
Congenital Cataract – A congenital cataract, or clouding of the crystalline lens is present in 2-3 per 10,000 live births of children. The presence of a visually significant cataract in a child is considered an urgent disorder. The resultant form deprivation of vision requires immediate surgery to remove the obstruction, prompt optical correction and amblyopia therapy in unilateral cases. Until the 1970s, it was generally believed that there was no means of restoring the vision in an eye with a unilateral congenital cataract. However, subsequent studies demonstrated that excellent visual results could be obtained with early surgical treatment coupled with optical correction with a contact lens and patching therapy of the fellow eye. However, treatment results continue to be poor in some infants with unilateral congenital cataracts due to a delay in treatment or poor compliance with contact lens wear or patching therapy of the fellow eye. The Infant Aphakia Treatment Study (IATS) was designed to compare the visual outcomes in children 1 to 6 months of age with a unilateral congenital cataract randomized to optical aphakic correction with contact lenses or an intraocular lens (IOL). Children randomized to IOL treatment had their residual refractive error corrected with spectacles. Children randomized to no IOL had their aphakia treated with a contact lens. In previous publications we have shown that the visual results are comparable for these two treatments at 1 year of age, but significantly more of the infants randomized to IOL implantation required additional intraocular surgeries.
Accommodative Esotropia – Accommodative esotropia refers to a crossing of the eyes caused by farsightedness. Accommodative esotropia is a type of strabismus. Children who are farsighted easily and automatically focus on objects at distance and near through accommodation. As a result, a child who is farsighted usually does not have blurred vision. However, in some children who are farsighted, this accommodative effort is associated with a reflex crossing of the eyes. Accommodative esotropia can begin anywhere from 4 months to 6 years of age. The usual age of onset is between 2 and 3 years of age.Full-time use of the appropriate hyperopic glasses prescription or contact lenses will often control the esotropia. When wearing the correction, the child will not need to accommodate and hence the associated eye-crossing reflex will disappear. However, after removing the prescribed correction, the crossing will reappear, perhaps even more than before the child began wearing the correction. Sometimes the correction will only cause the crossing to disappear when the child views a distant object. However, when gazing at near objects, crossing may persist despite the use of the correction. In these circumstances, a bifocal lens is often prescribed to permit the child to have straight eyes at all viewing distances. One potential advantage of contact lenses compared to spectacles when correcting hyperopic powers is the decrease in accommodative demand. The increased effort to converge the eyes with spectacles requires one to over come the resultant base out prism when viewing a near object.

Buddy Russell, FCLSA, COMT
Associate, Specialty Contact Lens Service
Emory University Eye Center

Nystagmus In Children

8/7/14

Nystagmus is a condition of uncontrolled eye movements. Patients with nystagmus are unable to maintain their eyes in a fixed position of focus. The movements can be pendular, swaying evenly side to side, or, jerk into one direction and drift toward the opposite direction. It can be present early in life or acquired as an adult. It can occur in eyes with poor vision from other anomalous development, or eyes that appear perfectly normal. In almost all patients the vision is compromised to some degree. In some patients, the eye movement is less, and the vision better, in an eccentric position that causes the patient to adopt a face turn, tilt or head posture so they can use this quieter position (“null point”) to navigate during their daily activities. To date there have been no consistently effective treatments for this condition.

Lingua and Grace - nystagmus — Dr. Lingua and Grace Nassar

Treatment efforts have been either medical (drugs to reduce the amplitude of the nytagmus movement) or surgical (to move the “null point” into straight ahead gaze to eliminate a head turn, or, directed at reducing the effective contracture of all the eye muscles to reduce the amount of movement). In general, surgical treatment of nystagmus has been disappointing.

In 2002, Dr. Robert Sinskey, noted cataract surgeon and phacoemulsification pioneer, proposed a revolutionary concept, that nystagmus could only be truly effectively controlled by removing the forward portion of the eye muscle and detach it completely from the eye. Since the twitching eye muscles were controlled by nerves sending that pulsatile information, any operation that allowed the muscles to remain attached to the eye would never quiet the movement. He performed this novel surgery in 2000 and published the results in 2002. It did not receive attention in the nystagmus surgery community, as most experts worried that the surgery would limit normal eye movements excessively. The operation does remove the forward portion of the eye muscle but, surprisingly, the eyes are still able to move to allow reading, computing, and driving.. In 2012, I had the opportunity to view a patient he operated 10 years prior and was impressed with how successful the results were even after 10 years. Coincidentaly, I was caring for a 17 year-old patient with nystagmus who had already undergone the 2 currently accepted eye muscle procedures for nystagmus without success. His movements remained uncontrolled, he could not maintain eye contact with anyone, and is his vision was less than that needed for a drivers license. In 2013, I offered him the Sinskey procedure and the results were remarkable. His nystagmus was quieted, his vision improved (20/25) enough to qualify for a drivers license and to return to school.

Since 2012, we have adapted, augmented and perfected the procedure and performed the surgery on over 12 patients with similar remarkable results. All patients experience a marked reduction in the amplitude of the nystagmus (60-100%), and all patients demonstrate improved vision (1-8 lines of the acuity chart), especially at the reading position.

Visit the YouTube posting “Meet Grace” for an example of how this surgery can impact a child’s life and the hopes of their parents. Visit www.eye.uci.edu for further information, contact information and scientific data on the procedure.

Robert W. Lingua, MD
Director, Pediatric Ophthalmology and Strabismus
Gavin Herbert Eye Institute, UC Irvine

Learning-Related Vision Problems

7/29/14

Next month is Children’s Eye Health Month, and to kick it off a little early we are taking a look at learning-related vision problems. Next month children start heading back to school, so now is the perfect time to make sure you child has had a recent comprehensive eye exam.

Vision and learning are closely related. About 80% of what a child learns in school is presented visually, and 25% of school-aged children already have vision problems (5-10%of preschoolers do). By scheduling a comprehensive eye exam for your child before school starts, you will help your child be more successful and happier in school.

When children have difficulty in school, from being able to see what is written on the whiteboard to learning to read, it not only makes the learning difficult, but it also makes the child frustrated and can affect their love of learning as well. While most schools perform a quick eye check at some point during the school year to determine simple refractive errors such as nearsightedness, farsightedness and astigmatism, there are other visual disorders that can make learning difficult.

Vision is a complex process that involves the eyes working well with the brain. Specific learning-related vision problems can be classified as one of three types. The first two types primarily affect visual input. The third primarily affects visual processing and integration.

Refractive vision problems. Your child holds a book close to their face when reading or they have difficulty seeing things that are far away. These are generally refractive issues and include nearsightedness, farsightedness and astigmatism, but could also include more subtle optical errors called higher-order aberrations.
Functional vision problems. This type of problem refers to a variety of specific functions of the eye and the brain’s control of these functions, such as eye teaming (using the eyes together), fine eye movements, and focusing skills, peripheral awareness and eye-hand coordination. These issues can cause blurred or double vision, eye strain and headaches.
Perceptual vision problems. Visual perception includes understanding what you see, identifying it, judging its importance and relating it to previously stored information in the brain. Examples would include recognizing words that you have seen before and being able to form a mental picture of the words you see.

Because most routine school and pediatrician eye exams evaluate only the refractive vision problems, it is wise to see optometrist who specializes in children’s vision problems to evaluate functional vision problems and perceptual vision problems that may affect learning.

Color blindness is not considered a learning-related vision problem, but it can cause problems for very young children if color-matching or identifying specific colors are part of the classroom activities. For this reason, make sure your child’s eye exam includes a color blind test prior to starting school.

Symptoms of Learning-Related Vision Problems:

Headaches, eye strain, excessive blinking or rubbing the eyes
Blurred vision or double vision
Crossed eyes or if the eyes move independently of each other
Holding a book very close to their face for reading
Bending way over a table to get closer to what they are drawing or writing
Using only one eye by tilting the head or covering the other eye
Losing their place while reading, or needing to use a finger to stay on line
Slow reading speed or poor reading comprehension
Omitting or repeating words, or confusing similar words
Persistent reversal of words or letters (after second grade)
Difficulty remembering, identifying or reproducing shapes
Poor eye-hand coordination
Distracted in class

If your child shows one or more of these symptoms, they could indicate a learning-related vision problem. To find out see an eye doctor who specializes in children’s vision for a comprehensive evaluation. If no vision problem is detected, your child’s problems could be caused by a non-visual issues, such as dyslexia or a learning disability, in which case you would need to contact an educational specialist for an evaluation.

Treatment of Learning-Related Vision Problems

If your child is diagnosed with a learning-related vision problem, treatment generally consists of an individualized and doctor-supervised program of vision therapy. Special eyeglasses also may be prescribed for either full-time wear or for specific tasks such as reading.

Remember that when children have a difficult time learning, especially while other classroom friends have no visual issues to impair learning, they may experience emotional problems as well, such as anxiety, depression and low self-esteem.

Reassure your child that learning-related vision problems do not relate to how smart they are and with the proper treatment and/or eyeglasses, things will become easier.

Susan DeRemer, CFRE
Vice President of Development
Discovery Eye Foundation

Ways to Reduce the Harmful Effects of Sun Glare

During the height of summer sunshine (and heat!), it’s helpful to discuss the importance of eye protection, including ways to reduce the harmful effects of sun glare.

Fundamentally, we need light to see. Approximately 80% of all information we take in is received through the sense of sight. However, too much light – and the wrong kind of light – can create glare, which can affect our ability to take in information, analyze it, and make sense of our surroundings.

Facts about Sunlight

Every type of light has advantages and disadvantages, and sunlight is no exception:

Advantages:

• Sunlight is the best, most natural light for most daily living needs.
• Sunlight is continuous and full-spectrum: the sun’s energy at all wavelengths is equal and it contains all wavelengths of light (explained below).

Disadvantages:

• It is difficult to control the brightness and intensity of sunlight.
• Sunlight can create glare, which can be problematic for many people who have low vision.
• Sunlight is not always consistent or reliable, such as on cloudy or overcast days.

Visible Light and Light Rays

An important factor to consider is the measurement of visible light and light rays, beginning with the definition of a nanometer:

• A nanometer (nm) is the measurement of a wavelength of light.
• A wavelength is the distance between two successive wave crests or troughs:

• A nanometer = 1/1,000,000,000 of a meter, or one-billionth of a meter. It’s very small!

The human visual system is not uniformly sensitive to all light rays. Visible light rays range from 400 nm (shorter, higher-energy wavelengths) ? 700 nm (longer, lower-energy wavelengths).

The visible light spectrum occupies just one portion of the electromagnetic spectrum, however:

• Below blue-violet (400 nm and below), is ultraviolet (UV) light.
• Above red (700 nm and above), is infrared (IR) light.
• Neither UV nor IR light is visible to the human eye.

Ultraviolet Light and Blue Light

Ultraviolet (UV) light has several components:

• Ultraviolet A, or UVA (320 nm to 400 nm): UVA rays age us.
• Ultraviolet B, or UVB (290 nm to 320 nm): UVB rays burn us.
• Ultraviolet C, or UVC (100 nm to 290 nm): UVC rays are filtered by the atmosphere before they reach us.

Blue light rays (400 nm to 470 nm) are adjacent to the invisible band of UV light rays:

• There is increasing evidence that blue light is harmful to the eye and can amplify damage to retinal cells.
• You can read more about the effects of blue light at Artificial Lighting and the Blue Light Hazard at Prevent Blindness.

A new study from the National Eye Institute confirms that sunlight can increase the risk of cataracts and establishes a link between ultraviolet (UV) rays and oxidative stress, the harmful chemical reactions that occur when cells consume oxygen and other fuels to produce energy.

Sunlight and Glare

Glare is light that does not help to create a clear image on the retina; instead, it has an adverse effect on visual comfort and clarity. Glare is sunlight that hinders instead of helps. There are two primary types of glare.

Disability glare

• Disability (or veiling) glare is sunlight that interferes with the clarity of a visual image and reduces contrast.
• Sources of disability glare include reflective surfaces (chrome fixtures, computer monitors, highly polished floors) and windows that are not covered with curtains or shades.

Discomfort glare

• Discomfort glare is sunlight that causes headaches and eye pain. It does not interfere with the clarity of a visual image.
• Sources of disability glare include the morning and evening positions of the sun; snow and ice; and large bodies of water, (including swimming pools).

Controlling Glare

You can protect your eyes from harmful sunlight and minimize the effects of glare by using a brimmed hat or visor in combination with absorptive lenses.

• Absorptive lenses are sunglasses that filter out ultraviolet and infrared light, reduce glare, and increase contrast. They are recommended for people who have low vision and are also helpful for people with regular vision.
• Lens colors include yellow, pink, plum, amber, green, gray, and brown. Ultra-dark lenses are not the only choice for sun protection.
• Lens tints in yellow or amber are recommended for controlling blue light.
• NoIR Medical Technologies: NoIR (No Infra-Red) filters absorb UVA/UVB radiation and also offer IR light protection.
• Solar Shields: Solar Shields absorb UVA/UVB radiation and are available in prescription lenses.
• You can find absorptive lenses at a specialty products store, an “aids and appliances store” at an agency for the visually impaired, or a low vision practice in your area. Before you purchase, it’s always best to try on several different tints and styles to determine what works best for you.

More Recommendations

• Always wear sunglasses outside, and make sure they conform to current UVA/UVB standards.
• Be aware that UV and blue light are still present even when it is cloudy or overcast.
• Make sure that children and older family members are always protected with UVA/UVB-blocking sunglasses and brimmed hats or visors.

Maureen A. Duffy, CVRT
Social Media Specialist, visionaware.org
Associate Editor, Journal of Visual Impairment & Blindness
Adjunct Faculty, Salus University/College of Education and Rehabilitation

20 Facts About Eye Color and Blinking

7/15/14

Eye color is one of the first things a person notices about another person, but blinking is so automatic we rarely think about it. Here are some intriguing facts about eye color and blinking:

1. The world’s most common eye color is brown.

2. Brown eyes are actually blue underneath.

3. Melanin affects the color of your eyes so brown eyes have more melanin than blue eyes.

4. Heterochromia is when you are born with two differently colored eyes.

5. Blue-eyed people share a common ancestor with every other blue-eyed person in the world.

6. We blink more when we talk.

7. It is impossible to sneeze with your eye open.

8. The average person blinks 12 times per minute or about 10,000 blinks per day.

9. The eye is the fastest muscle in the body – in the blink of an eye. They are also the most active muscles in the body.

10. A blink usually lasts 100 to 150 milliseconds making it possible to blink five times in a second.

11. You blink less when you’re reading.

12. Infants blink 10 times less than adults.

13. One blink isn’t always the same as the next.

14. Our eyes close automatically to protect us from perceived dangers.

15. The older we are the less tears we produce.

16. Tears are made of three main components – fat, mucous and water. This is so tears won’t evaporate.

17. Your nose gets runny when you cry as the tears drain into your nasal passages.

18. You blink on average 4,200,000 times a year.

19. Tears kill bacteria because they contain lysozyme, a fluid that can kill 90 to 95 percent of all bacteria.

20. A newborn baby will cry, but not produce any tears. Babies do not produce tears until they are around six weeks old.

Susan DeRemer, CFRE
Vice President of Development
Discovery Eye Foundation

Food for Thought . . .

6/26/14

Can dinner really be delicious medicine for our eyes?

Recent studies have shown compelling evidence that specific nutrients support eye health.* When a vitamin or mineral is given as a supplement, are there the supporting micronutrients and enzymes required for optimal utilization of that supplement by our bodies? Is a nutrient more bioavailable and/or more beneficial to our health as a foodstuff than as a supplement? Are there unintended effects from supplements that are not present when the nutrient is derived from a food source?**

Despite the many thought provoking questions, I personally take supplements as I feel it is difficult to acquire the nutrients strictly through food. Dietary preferences and requirements influence our everyday food choices as well as the quality of food available at our local grocery stores. Thoughtfully designed, well-sourced supplements have been shown to enhance eye health and general well being.
Here are some key nutritional principles which should be kept in mind to maximize the nutrient availability to our eyes and bodies from the foods that we eat:

1. Bioavailability: Vitamins A, D, E and K are fat soluble; the vitamin B-complex and vitamin C are water soluble. Dietary fats aid in the transport of fat soluble vitamins. Of particular importance to eye health are the fat soluble carotenoids in the vitamin A family, lutein and zeaxanthin. Carotenoids are the red, orange and yellow pigments found in fruit and vegetables such as kale, spinach, corn, apricots and orange bell peppers. To maximize their nutritional benefit, combine foods rich in carotenoids with a healthy source of fat such as olive oil, avocados or walnuts. Egg yolk contains the most bioavailable source of lutein and zeaxanthin and is preferentially deposited in the macula.

2. Nutrient Synergy: Nutrient synergy is the interaction of two or more nutrients that work together to achieve a greater effect than a single nutrient alone could. Foods have a vast array of micronutrients. We know that spinach contains a high level of lutein; however, we don’t know precisely how all the nutrients in spinach work together to promote eye health. Epidemiological studies show people who eat spinach have a lower risk for developing Age-related Macular Degeneration (AMD). Levels of lutein and zeaxanthin in the macula can be measured and low levels are a predictor for the risk of developing AMD.

3. Growing and Feeding Practices: The growing and feeding practices of the agriculture industry affect the nutrient profile and nutrient density of our food. Grass-fed versus corn-based animal husbandry, and wild versus farm-raised fish, alters the fatty acid profile. The amount of omega-3 fatty acids found in eggs varies depending upon the chicken’s diet. Ketchup from organically grown tomatoes contains nearly 50% more lycopene than from conventionally grown tomatoes. Choose quality ingredients whenever possible.

4. Cooking Techniques: Steaming, sautéing or pureeing will break down the plant cell walls increasing the body’s access to the lutein found in dark leafy greens. Cooking tomatoes will increase the availability of lycopene. Heat, however, diminishes the amount of vitamin C present. To maximize lutein and vitamin C, consume both fresh and cooked vegetable sources. Excessive heat and lengthy cooking times diminish vitamin content (mineral content will remain intact, however).

5. Whole Foods: Whole foods have benefits such as soluble and insoluble fiber which help to regulate blood sugar. Foods high in fiber have been shown to decrease total cholesterol, triglycerides and VLDL levels. Fiber supports gut health which is integral to nutrient absorption.

6. Select Eye Nutrient Dense Foods: Studies have highlighted lutein+zeaxanthin, the omega-3 fatty acids balanced with omega-6 fatty acids, the vitamin A family, the antioxidant vitamins C and E, as well as the mineral zinc. There a number of other nutrients that play a role in eye health including B vitamins, selenium and other plant based antioxidants. Knowing the food sources of these important nutrients will help you to make better food choices for eye health.

How does this sound for dinner tonight? Grilled wild salmon on a bed of lightly sautéed spinach with caramelized onions!

* AREDS 1, 2; LAST: Lutein Antioxidant Supplement Trial; ZVF: Zeaxanthin and Visual Function
** CARET: Carotene and Retinal Efficacy Trial

Sandra Young, OD
Author of the award winning Visionary Kitchen: A Cookbook for Eye Health
www.visionarykitchen.com

My New Vision With A Telescope Implant

6/19/14

What it’s like to see with the CentraSight telescope implant

Like many people, I’ve set goals in my life, both professionally and personally and like being an active and engaged member of my community and my country. I love to teach: I taught history, geography and special education for years in Banning, California and now live in Moreno Valley, California, with my wife of 32 years, Kay. I love my country: I’m a proud veteran of both the Army Reserve and the Navy. And I love an open road. My wife and I traveled the country visiting historical monuments in our 32-foot RV. I guess I’ve got what you’d call a real zest for life. But, over the past twenty years, all the things I enjoyed doing in my life, even the simple day-to-day activities, started to decline because I was slowly losing my vision due to age-related macular degeneration. For example, six years ago, my wife took over all the driving because I couldn’t see well enough to drive safely.

Roy Kennedy - telescope implant — Roy Kennedy

That was a real turning point for me. My wife had to help me so much because I just couldn’t see. I needed help shopping because I couldn’t read labels. I started to avoid social situations, like visiting with friends because I was embarrassed that I couldn’t recognize faces any longer. As you can imagine it was heartbreaking for both me and my wife.

But then my doctor told me about a treatment I wasn’t yet aware of called the telescope implant. The device is very small (smaller than a pea!), and it is implanted in one eye to restore vision. My doctor explained that it works like a real telescope in that it magnifies images, which reduces the effect of the blind spot on my straight-ahead vision. The other eye does not get an implant because you need to keep some peripheral vision to help with orientation and balance. This sounded like science fiction! But I wanted to see if it could help me and I decided to give it a try.

I worked with a great team of specialists, who were part of a treatment program called CentraSight. My retina doctor, cornea surgeon, low vision optometrist and a low vision occupational therapist all counseled me about what to expect from the outpatient procedure, particularly afterwards. For example, I learned there was a significant amount of occupational therapy required to adjust and become proficient at using my new vision. I also was warned that my sight would not be like it was in my youth. I wouldn’t be able to do everything I used to nor would I be able to see, differently, the minute I opened my eyes.

I had my surgery in early 2013. The cost for the telescope implant and visits associated with the treatment program were covered by Medicare, which was very helpful. Thinking back, I was nervous on surgery day, but afterwards, I was told by my occupational therapist that I was one of the quickest to recover from surgery. I give lots of credit to my OT folks as well as my wife who helped me with the exercises at home. The most amazing part is being able to see my wife’s face again for the first time in six years! I’ve regained the ability to do many everyday tasks, like reading, working on my computer and watching old Westerns on TV. My wife and I are even back to traveling the open road in our RV (which she drives)!

I would recommend people learn more about the telescope implant to see if it might help them, the way it helped me. There are CentraSight teams across the country. When you call 1-877-99-SIGHT or visit www.CentraSight.com a trained CentraSight information Specialist will point you to the team closest to your home and can even help schedule the appointments for you. The telescope isn’t for anyone, but it can make such a difference in your life. It certainly did in mine.

Roy Kennedy

What Are Floaters? | Causes and Treatment

6/12/14

Floaters can be anything seen in your vision that moves “to and fro” with your eye movement. The movement is not stationary compared to a blind spot which is fixed or stationary in your field of vision.

The key is that the position changes with eye movement. Size, shape, color, etc. don’t matter. Anything that moves in your vision is called a floater.

Remember, if you experience new floaters; please see an eye doctor for an examination.

Here are some common causes of floaters:

Posterior Vitreous Detachment (PVD)

Retinal Tears

Blood (Vitreous Hemorrhage) can be caused by;

Advanced Diabetic Retinopathy

Retinal Tears

Retinal Vascular Occlusions

Inflammation or Infection

Asteroid Hyalosis

Posterior Vitreous Detachment
A posterior vitreous detachment (PVD) is a common cause of floaters. A PVD occurs when the vitreous separates from the retinal surface. This is a normal event and will eventually occur in everyone. Retinal tears are more likely to occur right after a PVD has started.

The vitreous is usually a clear watery gel. As we age, enough of the proteins in the vitreous liquefy and degenerate. Eventually, there is a physical separation of the vitreous from the retina due to this liquefaction.

“Floaters” can develop due to opacities/haziness due to the aging gel which is no longer absolutely clear due to changes in the optical properties of the gel or the interface between the vitreous and water inside the eye.

Tears in the Retina
Retinal tears can cause floaters by either causing a small vitreous hemorrhage, or by dislodging cells into the vitreous which are normally located underneath the retina.

Vitreous Hemorrhage
Blood in the vitreous can also cause floaters. A so-called vitreous hemorrhage may result from either a retinal tear or advanced diabetic retinopathy. Occasionally, retinal vascular occlusions can also lead to bleeding in the vitreous.

Blood in the eye often absorbs, but only your doctor can determine the exact nature of the floaters and if they are associated with a retinal tear. It’s impossible for you to tell the cause of floaters without a proper dilated eye exam.

Inflammation
Certain types of inflammation or infection can cause significant floaters. Actually, these are white cells which migrate to the retina and vitreous and can be seen a floaters.

Asteroid Hyalosis
This is a common entity where lots of fine white opacities are suspended in the vitreous. In most cases, these are not noticed by the patient. Sometimes, however, the so-called asteroid bodies are so dense they prevent good examination of the retina. Other times, especially after a PVD, the asteroid bodies are noticed and patients may complain of floaters.

New Floaters: Evaluation
All new floaters must be examined by your eye doctor within 24-72 hours after occurring. Even if the floaters disappear in that time frame, you should be examined to look for a possible tear in the retina.

Again, you, the patient, can NOT tell the cause of the floaters or if you’ve sustained a retinal tears. Retinal tears can cause a retinal detachment – a potentially blinding problem.

Treatment of Floaters
There are no medicines or eye drops to treat floaters. Most doctors advise simply putting up with the floaters.

For patients who have chronic problems with floaters, I recommend a vitrectomy. A vitrectomy is an eye operation, performed by a retinal specialist. The operation is comparable to a cataract operation in terms of safety and possible complications.

There are a handful of doctors who perform Yag laser to break up floaters.

Randall V. Wong, MD
Retina Specialist
Fairfax, Virginia

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