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New Research: Results from the Philadelphia Glaucoma Detection and Treatment Project

a view of the eye to check for glaucoma

New glaucoma research, initially presented at the American Glaucoma Society 24th Annual Meeting, concludes that targeting individuals at risk for glaucoma in underserved communities – in this case, Philadelphia – can yield a high detection rate of glaucoma-related diagnoses. The authors conclude that "providing examinations and offering treatment at community-based sites providing services to older adults are effective ways to improve access to eye care by underserved populations."

This new glaucoma detection research, entitled The Philadelphia Glaucoma Detection and Treatment Project: Detection Rates and Initial Management, has been published online ahead-of-print in the May 22, 2016 edition of Ophthalmology, the official journal of the American Academy of Ophthalmology. Ophthalmology publishes original, peer-reviewed research in ophthalmology, including new diagnostic and surgical techniques, the latest drug findings, and results of clinical trials.

The authors are Michael Waisbourd, MD; Noelle L. Pruzan, MD; Deiana Johnson, MPH; Angela Ugorets, BS; John E. Crews, DPA; Jinan B. Saaddine, MD; Jeffery D. Henderer, MD; Lisa A. Hark, PhD, RD; and L. Jay Katz, MD, who represent the following institutions: Wills Eye Hospital Glaucoma Research Center, Philadelphia, PA; Vision Health Initiative, Centers for Disease Control and Prevention, Atlanta, GA; and Lewis Katz School of Medicine at Temple University, Philadelphia, PA.

About the Philadelphia Glaucoma Detection and Treatment Project

Excerpted from Reducing Barriers to Glaucoma Screening: A community-based project in Philadelphia increased access to care in high-risk populations, an interview with Project principals L. Jay Katz, MD; Michael Waisbourd, MD; and Lisa A. Hark, PhD, RD, via eyetubeOD:

Sometimes the work we do in the interest of research affords us the opportunity to have tremendous impact on the communities we serve as physicians. Such is the case with the community-based mobile glaucoma program initiated by the Wills Eye Hospital Glaucoma Service and Glaucoma Research Center.

The program, called the Philadelphia Glaucoma Detection and Treatment Project, was a demonstration project designed to find out if it might be possible to bring the tools needed to diagnose and treat glaucoma to high-risk populations, rather than waiting for patients to come to us. Patients were educated, enrolled, examined, and, if a diagnosis was positive, offered a same-day, on-the-spot intervention, such as laser therapy.

Traditionally, screening programs have a significant problem with follow-up. For one reason or another, often despite the best intentions, many patients diagnosed with an eye disease through screenings get lost to follow-up, and, hence, an opportunity for treatment is lost. Glaucoma is particularly insidious on this account, as the disease burden is often highest among those who have suboptimal access to care. This is a big reason why almost half of all glaucoma cases go undetected.

This ongoing program has two objectives: (1) to establish community partners, such as senior centers, that can be used as sites to identify patients in need of glaucoma services, and (2) to conduct educational workshops and comprehensive eye examinations in these community sites, immediately connecting patients in need of treatment with care.

For the program, we sent a mobile unit staffed with an ophthalmologist and stocked with diagnostic [and treatment] equipment … to 43 program sites (senior centers, senior housing buildings, and community centers) in areas with a high population density of African American individuals in West Philadelphia, North Philadelphia, Northeast Philadelphia, and South Philadelphia. Our experts led awareness workshops to educate patients about glaucoma and recruit into the program.

Each patient who enrolled received a complete eye examination at no cost… More than 1,600 patients were enrolled; African American patients had to be older than 50 years, and others had to be older than 60 years. Patients who were positively diagnosed with any type of glaucoma were followed up at the community sites.

We received generous support … in the form of a donated [laser] so that we could offer patients on-the-spot treatment options, specifically selective laser trabeculoplasty (SLT) for individuals with open-angle glaucoma and laser peripheral iridotomy (LPI) procedures for those with anatomically narrow angles.

[Editor's note: You can learn more about laser peripheral iridotomy (LPI), selective laser trabeculoplasty (SLT), and eye drops to lower eye pressure at What Are the Different Treatments for Glaucoma? on the VisionAware website.]

We returned to each program site at least twice: 4 to 6 weeks after the initial visit to assess those who had glaucoma or who had received a laser treatment, and at 4 to 6 months after the initial examination. Through the program, we learned a lot more than we expected. A significant number of patients were diagnosed with glaucoma-related conditions, including glaucoma, glaucoma suspect, or narrow angle. Other eye diseases were also detected.

You can read the authors' interview in its entirety, including the project results, at Reducing Barriers to Glaucoma Screening: A community-based project in Philadelphia increased access to care in high-risk populations.

What Is Glaucoma?

The term "glaucoma" describes a group of eye diseases that can lead to blindness by damaging the optic nerve. It is one of the leading causes of vision loss and blindness. The human eye continuously produces a fluid, called the aqueous, that must drain from the eye to maintain healthy eye pressure.

Types of Glaucoma

In primary open-angle glaucoma, the most common type of glaucoma, the eye's drainage canals become blocked, and the fluid accumulation causes pressure to build within the eye. This increasing pressure can cause damage to the optic nerve, which transmits information from the eye to the brain. Vision loss is usually gradual and often there are no early warning signs.

In angle-closure glaucoma, also called "acute" glaucoma, the aqueous cannot drain properly because the entrance to the drainage canal is either too narrow or is closed completely. In this case, eye pressure can rise very quickly and cause an acute glaucoma attack. Symptoms can include sudden eye pain, nausea, headaches, and blurred vision. Acute glaucoma is a true ocular emergency and requires immediate treatment.

In normal-tension glaucoma, also called low-tension/low pressure glaucoma, individuals with the disease experience optic nerve damage and subsequent vision loss, despite having normal intraocular [i.e., within the eye] pressure (IOP).

Most eye care professionals define the range of normal IOP as between 10 and 21 mm Hg [i.e., millimeters of mercury, which is a pressure measurement]. Most persons with glaucoma have an IOP measurement of greater than 21 mm Hg; persons with normal-tension glaucoma, however, have an IOP measurement within the normal range.

Visual Field Loss

Glaucoma results in peripheral (or side) vision loss initially, and the effect as this field loss progresses is like looking through a tube or into a narrow tunnel. This constricted "tunnel vision" effect makes it difficult to walk without bumping into objects that are off to the side, near the head, or at foot level.

A living room viewed through a constricted visual field

A living room viewed through a constricted visual field.
Source: Making Life More Livable. Used with permission.

Glaucoma is an especially dangerous eye condition because most people do not experience any symptoms or early warning signs at the onset. Glaucoma can be treated, but it is not curable. The damage to the optic nerve from glaucoma cannot be reversed.

More about the Study from Ophthalmology

From the study summary and abstract:

Purpose; To evaluate the detection rates of glaucoma-related diagnoses and the initial treatments received in the Philadelphia Glaucoma Detection and Treatment Project, a community-based initiative aimed at improving the detection, treatment, and follow-up care of individuals at risk for glaucoma.

Participants: A total of 1,649 individuals at risk for glaucoma who were examined and treated in 43 community centers located in underserved communities of Philadelphia.

Methods: Individuals were enrolled if they were African American aged ≥ (greater than or equal to) 50 years, were any other adult aged ≥ (greater than or equal to) 60 years, or had a family history of glaucoma. After attending an informational glaucoma workshop, participants underwent a targeted glaucoma examination including an ocular, medical, and family history; visual acuity testing, intraocular [i.e., within the eye] pressure (IOP) measurement, and corneal pachymetry; slit-lamp and optic nerve examination; automated visual field testing; and fundus color photography.

[Editor's note: You can read more about all of these diagnostic tests for glaucoma at How Can I Detect Glaucoma if There Are No Initial Symptoms? on the VisionAware website.]

If indicated, treatments included selective laser trabeculoplasty (SLT), laser peripheral iridotomy (LPI), or IOP-lowering medications. Follow-up examinations were scheduled at the community sites after 4 to 6 weeks or 4 to 6 months, depending on the clinical scenario.

[Editor's note: You can learn more about laser peripheral iridotomy (LPI), selective laser trabeculoplasty (SLT), and eye drops to lower eye pressure at What Are the Different Treatments for Glaucoma? on the VisionAware website.]

Results: Of the 1,649 individuals enrolled, 645 (or 39.1%) received a glaucoma-related diagnosis; 20% were identified as open-angle glaucoma suspects, 9.2% were identified as having narrow angles (or as a primary angle closure/suspect), and 10.0% were diagnosed with glaucoma, including 9% with open-angle glaucoma and 1% with angle-closure glaucoma.

Overall, 39% of those diagnosed with glaucoma were unaware of their diagnosis. A total of 196 patients (11.9%) received glaucoma-related treatment, including 84 who underwent laser peripheral iridotomy (LPI), 13 who underwent selective laser trabeculoplasty (SLT), and 103 who were prescribed eye pressure-lowering medication.

Conclusions: Targeting individuals at risk for glaucoma in underserved communities in Philadelphia yielded a high detection rate (39.1%) of glaucoma-related diagnoses. Providing examinations and offering treatment, including first-line laser procedures, at community-based sites providing services to older adults are effective to improve access to eye care by underserved populations.

More about Glaucoma at VisionAware

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Our Readers Want To Know: Can I Continue Gardening with Vision Loss?

flowers in window box

Editor's note: One of the many benefits associated with an online information center and website, such as VisionAware, is the ability to hear from our readers and implement their suggestions for keeping VisionAware relevant, timely, and useful. Most recently, our reader interactions have included several inquiries about hobbies or recreational activities for adults and older adults with vision loss:

  • I would like to help a social director in an independent living facility find activities that are appropriate for people with vision loss/macular degeneration. Can you help?
  • Can you suggest activities or hobbies that would be fun for older adults with very limited – or no – vision?

What about Gardening?

With the first day of summer fast approaching on June 20, it's appropriate (and timely) to enjoy the sensory and physical joys of gardening, along with helpful adaptations for gardeners with vision loss.

Use Colorful and Tactile Borders

  • Use commercial edging products, such as crushed stone, bricks, pavers, pieces of lumber, or fencing to mark where one area ends and another begins.
  • Use planking, long boards, rocks, or bricks to mark off the outer edges of your garden for easier location and separation from lawn or play areas.
rose garden and fence
  • Paint your fencing or stones in contrasting colors, such as white or yellow, that will contrast with the green grass.
  • Use textured and/or colorful materials, such as crushed white marble chips, natural wood chips, or crushed seashells.
  • Consider using natural or organic fertilizers and pest control treatments, especially if you use your uncovered hands to feel your plants or tend your garden.

Create Your Own Plant and Row Markers

  • If you have low vision, create large print labels with index cards and a wide-tip black marker. Laminate the cards or seal them in plastic sandwich bags. Attach each card to a small craft stick.
  • See Labeling and Marking and Large Print to help you make accessible labels for your plants.
  • Use brightly-painted stones in different colors to indicate the type of flower or plant. For example, white stone=daisies, red stone=tulips or tomatoes.
  • Yogurt cups with the bottoms removed can protect young plants. Sink the cup halfway into the soil and plant inside it. The cup will outline the area in which your seedlings are growing and can also help with weed control.
  • Use an egg carton as a planting spacer. Poke a one-inch hole in the bottom of each egg portion and position the egg carton/spacer on the soil. Place one seed into each hole and cover with soil. Remove the spacer gently, move it to a new section, and continue planting.
  • Lay down a fishing line or a cane and use it as a guide for planting straight rows.
  • If you form rows by running strings between stakes, you can secure old tennis balls or another type of tactile reminder on the top of each stake to help you identify the plants in each row.
  • A long-handled garden tool can also become a measuring stick by placing a piece of contrasting tape every six inches along the handle, or whatever distance you need to measure.

Try Container Gardening

a container garden

Container gardening is easy and can be very enjoyable. Flowers, herbs, and many vegetables grow well in containers – and even shallow six-inch-deep pots full of basil, parsley, or chives can sit on a porch rail. Container plants have several advantages, including:

  • They make it easier to identify plants and seed locations.
  • They let you garden anywhere without digging garden beds.
  • They allow you to have the best soil, moisture, and growing conditions for a particular plant.
  • They make changing a plant's location much easier.

Preparing Containers

Good soil is the foundation of a garden and allows plants to thrive. Try using topsoil or potting soil from a garden center to fill containers. The quality will be good and it will be free of weeds and weed seeds. Also, you'll have to do less weeding later in the season.

  • Use containers with good drainage holes in the bottoms. The holes must be small enough so that soil stays in the pot, but large enough to let excess water drain out. If water collects and pools in the bottom of a container, it will damage plant roots. Place a layer of small pebbles or wood chips in the bottom of the container, about half an inch deep, to absorb water and help with drainage.
  • Next, fill the container with soil, an inch from the top. That remaining inch is to allow water or falling rain to drain. If the container is full of soil to the rim, water might wash away seeds or the top layer of soil.

Planting the Seeds

  • Plant your seeds, following instructions for spacing. Try planting seeds and small plants in the same container. You can enjoy the small plants while the seeds are germinating and sprouting.
  • Use labels in large print or braille to mark containers. You can place the labels on the containers or on wood or metal markers that you can purchase at garden stores or make from Popsicle sticks. Use waterproof tape and wide-tip markers to create your own large print labels.

Your Gardening Tools

  • If you have low vision, look for commercially-produced garden tools with brightly colored handles that contrast with your grass, flower beds, or planting bench.
  • You can also apply tape or paint in colors that contrast with the handles of your favorite tools, or paint the tines of your rake to help with locating your tools and identifying your work area.
  • Use an apron, utility belt, or plastic carryall container to hold your gardening tools.
  • Use upper-body protective techniques to protect your face and eyes from injury when bending down in the garden.

Additional Gardening Information

Arts and Leisure
Environmental assessment and modification
Low Vision
Readers Want to Know
Social Life and Recreation

An Award-Winning Optometric Student Essay: Ethical Issues in Low Vision Rehabilitation

the ASCO logo

The Association of Schools and Colleges of Optometry (ASCO) is the academic leadership organization committed to promoting excellence in optometric education. ASCO's activities cover a wide range of educational issues related to optometry, including applicant development and diversity, faculty and executive development, advocacy, and communications.

ASCO also recognizes optometric student achievement through a number of annual awards, including the Student Award in Clinical Ethics, open to optometry students during any point in their educational programs at an ASCO-affiliated school or college of optometry in the United States, Puerto Rico, and Canada. To apply for the Clinical Ethics Award, a student must submit an essay that discusses any of the ethical theories and values that are involved in optometric patient care.

The 2016 Award Winner: A Low Vision Case Study

This year, the award recipient is Krystal Chee, O.D., from the School of Optometry, University of California, Berkeley, Class of 2016, for her essay that explores Rehabilitation of the Ethical Issues in Low Vision. In her essay, Dr. Chee explores the ethical issues she faced when working with a patient who came to the optometry clinic for a comprehensive eye exam, stating that she was "unable to see anything," but whose exam results indicated that she did not meet the criteria for classification as legally blind.

The patient's records documented a history of diabetic retinopathy, a macular hole, and macular scarring. Her medical history included type 2 diabetes and hypertension. At the conclusion of the exam, the patient requested a diagnosis of legal blindness and stated that she had received benefits through being legally blind in the past. She provided documentation of this diagnosis in the form of a letter from her previous ophthalmologist.

What Is Legal Blindness?

"Legal blindness" is a definition used by the United States government to determine eligibility for vocational training, rehabilitation, schooling, disability benefits, low vision devices, and tax exemption programs. It's not a functional definition and doesn't tell us very much at all about what a person can and cannot see.

Part 1 of the U.S. definition of legal blindness states this about visual acuity:

  • A visual acuity of 20/200 or less in the better-seeing eye with best conventional correction (meaning with regular glasses or contact lenses).

Snellen Eye Chart

  • If you can only read line 1 (the big "E") from 20 feet away while wearing your regular glasses or contact lenses, the doctor records your vision (or visual acuity) as 20/200 with best correction.
  • In 2007, the Social Security Administration updated the criteria for measuring legal blindness when using newer low vision test charts with lines that can measure visual acuity between 20/100 and 20/200. Under the new criteria, if a person's visual acuity is measured with one of the newer charts, and they cannot read any of the letters on the 20/100 line, they will qualify as legally blind, based on a visual acuity of 20/200 or less.

Part 2 of the U.S. definition of legal blindness states this about visual field:

  • OR a visual field (the total area an individual can see without moving the eyes from side to side) of 20 degrees or less (also called tunnel vision) in the better-seeing eye.

This is a representation of a constricted visual field:

A living room viewed through a constricted visual field

A living room viewed through a constricted visual field.
Source: Making Life More Livable. Used with permission.

You can read more about ways to classify vision at Low Vision and Legal Blindness Terms and Descriptions at

The Optometric Ethical Dilemma: Low Vision versus Legal Blindness

The following passage has been edited for clarity for non-medical readers and excerpted from Dr. Krystal Chee's award-winning essay and case study, which you can read in its entirety at Rehabilitation of the Ethical Issues in Low Vision on the ASCO website.

The Exam Results

During the exam, her visual acuities were as follows: counting fingers at 40 cm [about 16 inches] in her right eye and 20/50 in her left eye. Pinhole and manifest refraction showed no improvement in visual acuities. [Editor's note: In a manifest refraction, the doctor places lenses of various strengths in front of the patient's eyes and asks "Which is better, lens A or lens B?"]

Visual field testing revealed constricted visual fields in both eyes. The right eye's widest diameter of visual field was 15 degrees; the left eye's visual field was constricted at the top (superior) and at the bottom (inferior), but was a full 54 degrees side to side (horizontally). We informed the patient that eyeglasses would not improve her vision and advised her to schedule an appointment to be seen in our low vision clinic.

The patient then requested a diagnosis of legal blindness and stated that she had received benefits through being legally blind in the past. She provided physical documentation of this diagnosis in the form of a letter from her previous ophthalmologist, which stated that she was legally blind. Although she desired the benefits she had previously received, it was clear that she did not qualify as "legally blind" per the U.S. Social Security Administration's definition.

The Ethical Dilemma

As optometrists, we encounter situations in which we need to appropriately draw the line between patients with low vision and patients who can be defined as legally blind. The law defines legal blindness for public safety reasons (driving) as well as determining eligibility for disability benefits funded by the government.

In addition to monetary assistance, the government-funded programs for people with legal blindness (the Social Security Disability Insurance program and the Supplemental Security Income program) can also provide services including audio, large print, or braille resources. The Americans with Disabilities Act allows reasonable accommodations by employers to allow for equal employment opportunity, such as closed-circuit televisions and screen magnifiers.

What about Low Vision?

While these benefits are of great assistance to legally blind patients, there are many additional factors that factor into a patient's visual functionality aside from visual acuity and visual field (e.g. contrast sensitivity). While a patient may not qualify under the United States Social Security Administration's guidelines, use of their low vision can still be equally as challenging if these additional hindrances are present.

The Optometric Professional Code of Ethics: Considerations for Services

As stated in the American Optometric Association Code of Ethics, one of our duties is "to advance professional knowledge and proficiency to maintain and expand competence to benefit our patients." Our job as optometrists is to ensure that patients who qualify for these services are diagnosed and directed to the appropriate resources that would allow for beneficial services, providing the highest quality of life possible.

According to An Optometrist's Guide to Clinical Ethics, "optometrists must serve as patient advocates and help their patients receive the best available care." This means we must be up-to-date with requirements through the United States Social Security Administration and how to direct patients towards receiving disability benefits. While we are to be advocates for the well-being of our patients, we must also recognize that these benefits are not to be abused.

We have an "obligation to protect the health and welfare of society," including appropriate allocation of resources to those who are in serious need. Patients may desire the benefits of being classified as legally blind, especially if they have been granted these benefits in the past - as with the patient in this case report. While one of our ethical principles is to help others (beneficence), it is necessary to be truthful of our exam findings in order to uphold the code of ethics.

Additionally, we should consider rehabilitation of these patients in the way of low vision services and low vision devices. If we do not have the means to provide these services ourselves, we must follow the Code of Ethics which states our responsibility to "advise our patients whenever consultation with, or referral to another optometrist or other health professional is appropriate."

This goes along with being an advocate for our low vision patients, especially those who feel overwhelmed or helpless in their daily functioning because of their reduced vision. The United States Social Security Administration states that even if a patient is not "legally blind" per their definition, a visual impairment may still make them eligible for Social Security benefits on the basis of disability. For these cases, directing our patients to a Social Security Disability attorney or advocate may be the best option to help them benefit from necessary services.

The Resolution of This Case

Considering that this patient's visual acuity and the extent of visual field were both better than the definition of legal blindness per the United States Social Security Administration, we determined that we could not diagnose her with legal blindness, despite her previous documentation and receipt of benefits. We consulted thoroughly with our patient and advised her of all of her options for low vision rehabilitation.

Another aspect of our Code of Ethics is to strive to ensure that all patients have access to eye and vision care, regardless of transportation or financial limitations. We connected her to the local Department of Rehabilitation, which would be able to help set her up with services through our low vision clinic. We also advised her that despite not qualifying as legally blind, her visual impairment could still allow her to gain services through the Social Security Administration and that an advocate could help her determine the appropriate options.

After discussing at length the potential benefits of low vision services to improve her employment opportunities and quality of life, our patient was greatly thankful for our advocacy and was optimistic about maximizing functionality of her vision.

Readers: It's Your Turn

What is your reaction to Dr. Krystal Chee's award-winning essay? Please feel free to discuss your reactions in the comments section. We want to hear from you!

Additional Information

Diabetes and diabetic retinopathy
Low Vision
Macular Degeneration
Personal Reflections

New Research: The Number of Older Americans with Visual Impairment or Blindness Is Expected To Double By 2050

the JAMA Network logo

According to new demographic research addressing blindness, vision impairment, and low vision, the number of older Americans who have visual impairments or are blind is projected to double by 2050.

This important – and urgent – research, entitled Visual Impairment and Blindness in Adults in the United States: Demographic and Geographic Variations from 2015 to 2050, has been published "online first" in the May 19, 2016 edition of JAMA Ophthalmology. JAMA Ophthalmology is an international peer-reviewed journal published monthly by the American Medical Association.

The authors are Rohit Varma, MD, MPH; Thasarat S. Vajaranant, MD; Bruce Burkemper, PhD, MPH; Shuang Wu, MS; Mina Torres, MS; Chunyi Hsu, MPH; Farzana Choudhury, MBBS, MPH, MS, PhD; and Roberta McKean-Cowdin, PhD, who represent the following institutions: the Keck School of Medicine of the University of Southern California, Los Angeles, and the University of Illinois at Chicago Eye and Ear Infirmary.

Dr. Varma is also a co-author of a recent Los Angeles Latino Eye Study publication that examined the risk and prevalence of early and late stage age-related macular degeneration and its impact on quality of life for older Latinos.

About the Research

Excerpted from Visual impairment, blindness cases in U.S. expected to double by 2050 at National Institutes of Health (NIH) News Releases:

With the youngest of the baby boomers hitting 65 by 2029, the number of people with visual impairment or blindness in the United States is expected to double to more than 8 million by 2050, according to projections based on the most recent census data and from studies funded by the National Eye Institute, part of the National Institutes of Health. Another 16.4 million Americans are expected to have difficulty seeing due to correctable refractive errors such as myopia (nearsightedness) or hyperopia (farsightedness) that can be fixed with glasses, contact lenses, or surgery.

The researchers estimate that 1 million Americans were legally blind (meaning a visual acuity of 20/200 vision or worse) in 2015. Meanwhile, 3.2 million Americans had visual impairment in 2015 — meaning they had 20/40 or worse vision with best possible correction. Another 8.2 million had vision problems due to uncorrected refractive error.

Over the next 35 years, Varma and his colleagues project that the number of people with legal blindness will increase by 21 percent each decade to 2 million by 2050. Likewise, best-corrected visual impairment will grow by 25 percent each decade, doubling to 6.95 million.

The greatest burden of visual impairment and blindness will affect those 80 years or older, because advanced age is a key risk factor for diseases such as age-related macular degeneration and cataract.

In terms of absolute numbers, non-Hispanic whites, particularly white women, represent the largest proportion of people affected by visual impairment and blindness, and their numbers will nearly double. By 2050, 2.15 million non-Hispanic white women are expected to be visually impaired and 610,000 will be blind. "Based on these data, there is a need for increased screening and interventions across all population, and especially among non-Hispanic white women," [study co-author] Dr. Varma said.

African Americans currently account for the second highest proportion of visual impairment, but that is expected to shift to Hispanics around 2040, as the Hispanic population — and particularly the number of older Hispanics — continues to grow.

Hispanics have particularly high rates of diabetes, which is associated with diabetic eye disease, a treatable cause of visual impairment. African Americans are expected to continue to account for the second highest proportion of blindness and are at disproportionately high risk for developing glaucoma.

More about the study from JAMA Ophthalmology

Edited and excerpted from the study abstract:

Importance: The number of individuals with visual impairment and blindness is increasing in the United States and around the globe as a result of shifting demographics and aging populations. Tracking the number and characteristics of individuals with VI and blindness is especially important given the negative effect of these conditions on physical and mental health.

Objectives: To determine the demographic and geographic variations in visual impairment and blindness in adults in the U.S. population in 2015 and to estimate the projected prevalence through 2050.

Design, Setting, and Participants: In this population-based, cross-sectional [i.e., at one specific point in time] study, data were pooled from adults 40 years and older from six major population-based studies on visual impairment and blindness in the United States. Prevalence of visual impairment and blindness were reported by age, sex, race/ethnicity, and per-capita prevalence by state using the U.S. Census projections (January 1, 2015, through December 31, 2050).

Results: In 2015, a total of 1.02 million people were blind, and approximately 3.22 million people in the United States had visual impairment (VI), whereas up to 8.2 million people had visual impairment due to uncorrected refractive error. By 2050, the numbers of these conditions are projected to double to approximately 2.01 million people with blindness, 6.95 million people with VI, and 16.4 million with VI due to uncorrected refractive error.

The highest numbers of these conditions in 2015 were among non-Hispanic white individuals (2.28 million), women (1.84 million), and older adults (1.61 million), and these groups will remain the most affected through 2050. However, African American individuals experience the highest prevalence of visual impairment and blindness.

By 2050, the highest prevalence of VI among minorities will shift from African American individuals (15.2% in 2015 to 16.3% in 2050) to Hispanic individuals (9.9% in 2015 to 20.3% in 2050).

From 2015 to 2050, the states projected to have the highest per capita prevalence of VI are Florida (2.56% in 2015 to 3.98% in 2050) and Hawaii (2.35% in 2015 and 3.93% in 2050), and the states projected to have the highest projected per capita prevalence of blindness are Mississippi (0.83% in 2015 to 1.25% in 2050) and Louisiana (0.79% in 2015 to 1.20% in 2050).

The Dilemma: How Can You Maintain Your Independence After Vision Loss?

If you have experienced any loss of vision, there are many services and devices that can help you continue to live independently in your home and community. Vision rehabilitation services can help you regain self-sufficiency, improve your quality of life, and help you function independently, just as occupational and physical therapy restore the ability to function after a stroke or other injury. Although there is not one specific "road map" that is right for everyone, the following steps can help you locate services and training that are right for you.

Step 1: Start with your eye care professional

The best place to begin the vision rehabilitation process is to make an appointment with your own eye care professional:

  • An ophthalmologist is a medical or osteopathic physician who specializes in the medical and surgical care of the eyes and the prevention of eye disease. An ophthalmologist treats eye diseases, prescribes medications, and performs all types of surgery to improve, or prevent the worsening of, eye and vision-related conditions. An ophthalmologist will have the initials M.D. (Doctor of Medicine) or D.O. (Doctor of Osteopathy) after his or her name.
  • An optometrist is a health care professional who specializes in function and disorders of the eye, detection of eye disease, and some types of eye disease management. An optometrist is trained to examine the eyes for visual defects, diagnose problems or impairments, prescribe corrective glasses and contact lenses, and, in some states, perform certain surgical procedures. An optometrist will have the initials O.D. (Doctor of Optometry) after his or her name.

Step 2: Have a low vision examination

If your vision loss cannot be completely corrected by your regular eye care professional, a low vision specialist can conduct the needed eye examination and help you make the best use of your remaining vision.

  • Low vision optical devices use lenses to magnify images so that objects or print appear larger to the eye. Examples include magnifying reading glasses, stand magnifiers, hand-held magnifiers, and small pocket-sized telescopes. These special optical devices are different from regular glasses and magnifiers.
Reading with an illuminated stand magnifier

Reading with a lighted
stand magnifier

  • Non-optical devices and modifications do not use lenses to magnify images. Instead, they increase lighting levels, improve contrast, decrease the effects of glare, or increase print size to make objects and print more easily visible. Examples include high-intensity table or floor lamps, large print reading materials, reading stands, and absorptive sunglasses.
  • Adaptive daily living equipment includes devices that are designed to make everyday tasks easier to do with reduced or no vision. Clocks with large numerals, writing guides, needle threaders, large print or talking watches, large print and tactile labels, and talking pill bottles are examples of daily living equipment.
  • In addition, you, your eye care specialist, and other low vision service providers, such as social workers and specially trained therapists, will also discuss how you are adapting emotionally to your vision loss, whether you are motivated to learn a different way of doing things, and whether you have family and friends to support you.

Step 3: Investigate additional vision rehabilitation services

Vision rehabilitation services can help you function safely and independently in several critically important daily living areas:

Independent movement and travel:

Independent living and personal management:

Communication and technology:

Counseling and peer support:

Source: Making Life More Livable: Simple Adaptations for Living at Home After Vision Loss, Third Edition. Used with permission.

Additional Information

Diabetes and diabetic retinopathy
In the News
Low Vision
Macular Degeneration
Planning for the Future
Public Policy

New Research: Automobile Side Windows Do not Offer Sufficient Protection from UV Light, Increase the Risk of Cataracts and Other Eye Diseases

the sun creating glare

United States government regulations require automobile windshields to be made with laminated glass to lessen potential injury when shattered. The combination of laminated glass and extra-thick glass in front windshields provides protection against ultraviolet-A radiation.

However, new research from California indicates that automobile side windows do not provide the same level of protection against ultraviolet-A radiation compared to the front-facing windshield, which may increase the risk of cataracts and skin cancer for frequent drivers. In addition, there is increasing evidence that related "blue light" is harmful to the eye and can amplify damage to retinal cells, in eye diseases such as macular degeneration.

From JAMA Ophthalmology

This new automobile and ultraviolet light research, entitled Assessment of Levels of Ultraviolet A Light Protection in Automobile Windshields and Side Windows, has been published "online first" in the May 12, 2016 edition of JAMA Ophthalmology (formerly Archives of Ophthalmology). JAMA Ophthalmology is an international peer-reviewed journal published monthly by the American Medical Association. The study author is Brian S. Boxer Wachler, MD, from the Boxer Wachler Vision Institute, Los Angeles, California.

About the Research

Excerpted from UV-A May be linked to Increased Risks of Cataract Formation and Skin Cancer at NH Voice:

It is a long-known fact that prolonged exposure to ultraviolet A (UV-A) rays can raise the risk for skin cancer and cataracts. For the first time, a research team has indicated that side windows of the car don't offer enough protection from harmful sun rays.

A recent JAMA Ophthalmology study assessed the protection provided by front windshields and side windows of automobiles from ultraviolet A (UV-A) rays. The study found that protection was consistently high in the front windshields while it was lower and highly variable in side windows. Scientists say that the study findings may to some extent explain the reported increased rates of cataract in left eyes and left-sided facial skin cancer.

For the study, the outside ambient UV-A radiation along with UV-A radiation behind the front windshield and behind the driver's side window was measured in 29 automobiles from 15 manufacturers. The years of the automobiles ranged from 1990 to 2014, with an average of 2010. [The study] found that the average percentage of front-windshield UV-A blockage was 96%, higher than the average 71% of side-window blockage. A high level of side-window UV-A blockage (more than 90%) was found in four of 29 automobiles (14%).

"Automakers may wish to consider increasing the degree of UV-A protection in the side windows of automobiles. This could contribute to a higher prevalence of left eye cataracts and skin cancer on the left side of people's faces. Based on the new data, automakers may wish to consider increasing the degree of UV-A protection in the side windows of automobiles," says [study author] Dr. Brian Wachler.

Visible Light and Light Rays

When discussing sunlight and its damaging effects, 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.
  • One nanometer = 1/1,000,000,000 of a meter, or one-billionth of a meter. It's very small!
  • A wavelength is the distance between two successive wave "crests" (ups) or "troughs" (downs):
wavelengths of light rays

Visible light rays range from 400 nm (shorter, higher-energy blue wavelengths, bottom) to 700 nm (longer, lower-energy red wavelengths, top).

Ultraviolet Light and Blue Light

The human visual system is not uniformly sensitive to all light rays, however. The visible light spectrum occupies just one portion of the electromagnetic spectrum:

  • 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.
the full light spectrum

Ultraviolet Light

Ultraviolet (UV) light has several components:

  • Ultraviolet A, or UVA (320 nm to 400 nm): UVA rays age us and penetrate the skin more deeply than do UVB rays. It is now believed that UVA rays contribute to, and may even initiate the development of, skin cancers. They are also able to penetrate glass, unlike UVB rays.
  • Ultraviolet B, or UVB (290 nm to 320 nm): UVB rays burn us and play a key role in the development of skin cancer and photoaging [i.e., skin wrinkling and sun damage].
  • Ultraviolet C, or UVC (100 nm to 290 nm): UVC rays are filtered by the atmosphere before they reach us.

Blue Light

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.
  • A 2014 study from the National Eye Institute (a) confirmed that sunlight can increase the risk of cataracts and (b) established 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.
  • UV and blue light are still present even when it is cloudy or overcast.

Absorptive Sunglasses, UV Light, and Blue Light

Absorptive sunglasses help filter out bothersome glare and harmful light rays. Most sunglasses now block out ultraviolet light. However, to block out "blue" light, which causes concern for macular degeneration and other eye conditions, sunglasses need to have some amount of yellow in them.

The colors of sunglasses that contain some yellow and block out blue light are: amber, orange, amber/orange combination, plum, and yellow. Grey and green-grey colored sunglasses do not block out any blue light. Grey and green-grey sunglasses also do not provide contrast as well as do amber, orange, plum, and yellow.

absorptive lenses in amber fit over regular eyeglasses

Absorptive sunglasses
in amber fit over
regular eyeglasses

Some advantages of absorptive sunglasses are:

  • They can reduce glare, enhance or clarify vision in the sunlight, ease eye fatigue, and protect the eyes from injuries.
  • They block out harmful light rays. Most block out ultraviolet (UV) light, while amber, orange, plum, and yellow-colored sunglasses also block out blue light.
  • Amber, orange, plum, and yellow-colored sunglasses also help enhance or increase contrast.
  • Yellow-colored sunglasses are helpful for use indoors (reading, writing, doing handicrafts, using a computer) to reduce glare and enhance contrast.
  • They are generally inexpensive and easy to obtain.
  • They can be fitted over regular glasses, and they are available in clip-on or insert styles.
  • Please note: Clip-ons and inserts are usually not as effective as fit-over or wrap-around styles, since they do not block light from the top and sides.
  • It is recommended that you try on a range of colors and styles during the low vision examination to determine which color or colors work best for you.

You can learn more about absorptive sunglasses at Helpful Non-Optical Devices for Low Vision and Helpful Products and Technology for Living with Vision Loss.

More about the Study from JAMA Ophthalmology

Edited and excerpted from the study abstract:

Importance: Ultraviolet A (UV-A) light is associated with the risks of cataract and skin cancer.

Objective: To assess the level of UV-A light protection in the front windshields and side windows of automobiles.

Design: In this cross-sectional study [i.e., at one specific point in time], 29 automobiles from 15 automobile manufacturers were analyzed. The outside ambient UV-A radiation, along with UV-A radiation behind the front windshield and behind the driver's side window of all automobiles, was measured. The years of the automobiles ranged from 1990 to 2014, with an average year of 2010. The automobile dealerships were located in Los Angeles, California.

Main Outcomes and Measures: Amount of UV-A blockage from windshields and side windows. The average percentage of front-windshield UV-A blockage was 96% and was higher than the average percentage of side-window blockage, which was 71%. The difference between these average percentages is 25%. A high level of side-window UV-A blockage (more than 90%) was found in 4 of 29 automobiles (13.8%).

Conclusions and Relevance: The level of front-windshield UV-A protection was consistently high among automobiles. The level of side-window UV-A protection was lower and highly variable. These results may in part explain the reported increased rates of cataract in left eyes and left-sided facial skin cancer. Automakers may wish to consider increasing the degree of UV-A protection in the side windows of automobiles.

What You Can Do to Protect Yourself

  • Always wear sunglasses outside, and make sure they offer protection from UVA, UVB, and blue light.
  • Wear fit-over or wrap-around sunglass styles, since they block harmful light from the top and sides.
  • Be aware that UV and blue light are still present even when it is cloudy or overcast.
  • Wear a minimum of SPF 15 sunscreen outdoors and when driving.
  • Investigate UV-blocking window tints or tinted window film for your automobile. Before you invest in this option, however, it is important to determine if these tints are legal in your specific area.

Additional Information

Environmental assessment and modification
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Macular Degeneration
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