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Making print more readable

For visually impaired people reading is difficult because the contrast of the print is affected by reduced lighting. Also especially when their macula is involved, they cannot read small print.  Here are some guidelines to making print more accessible especially for students.

Using the highest contrast possible is best.  Use light letters on a dark background or dark letters on a light background. 

It is also preferable to use large print size, from about 16 point or 18 point at the least. 

The Font type should be recognizable characters,  using upper and lower case, avoiding italics, all caps, or slanted print.  Also do not use decorative fonts.  Recommended fonts are arial, verdana, and better if they can be bold.  

It is important to avoid glossy papers as they can cause glare. 

There must be adequate spacing between letters and words.  When the letters are too close to each other, they are especially difficult to read for persons with central field defects.  The recommended spacing between lines of text is 1.5 rather than single space, as recommended by the American Foundation for the Blind.  Also students may use a marker below the line to help them remain in the same line.  

An extra wide binding margin makes it easier to  the use low vision devices such as stand magnifiers and portable videomagnifiers, as it is better to read with these devices on a flat surface.  

Sometimes, all it takes to make life easier in school for students with visual impairment is to make print legible for them.  Simple adjustments can make a difference in a person’s life.

 

 

Retinitis Pigmentosa

Retinitis Pigmentosa is an inherited disease that affects the photoreceptor cells of the retina. These are cells that process light and help us to see. The first symptom is usually night blindness. Other symptoms are decrease in color vision, and eventually peripheral vision. When peripheral vision is progressively lost, this ends up in what is referred to as tunnel vision. This is like looking through a keyhole.

Since this is hereditary, family members should be screened for the disease.

To date, there is still no treatment for Retinitis Pigmentosa. As this disease is progressive, vision rehabilitation can help you maximize your visual potential through devices and solutions.

Glaucoma

Glaucoma is a progressive disease characterized by damage to the optic nerve usually caused by increased pressure within the eye.

The optic nerve is like a cable that connects the eye to the brain and functions to transmit visual impulses from the eye to the brain enabling us to see what is directly in front of our eyes or what we are directly looking at (central vision) as well as what is around what we are directly looking at (peripheral vision). The central vision and peripheral vision are what comprise our entire field of vision or the entire area that we see.

This optic nerve, however, is a sensitive part of the eye that functions normally within an optimal range of eye pressure. Beyond this optimal eye pressure range, the optic nerve can get damaged as what happens with glaucoma. When damaged, the optic nerve’s ability to transmit visual impulses becomes impaired, thus causing the visual symptoms. What usually gets affected first is the peripheral vision and it usually occurs gradually. That is why persons with glaucoma may not notice the visual disturbance in the early part of the disease. Without proper control of the disease, the damage to the optic nerve may progress and cause progressive narrowing of the field of vision making the area the eye can see smaller until it is as if you are looking through a peephole. With further damage glaucoma can cause blindness.

Aside from narrowing of the field of vision, glaucoma has other symptoms depending on whether it is the open-angle type or closed-angle type of glaucoma. It will also depend on the severity of the disease.

With the open-angle glaucoma, there is no detectable symptom during the early part of the disease. It is only in the latter part when vision is significantly affected that patients begin to notice they are unable to see certain portions of their vision or that vision is not as clear as before.

Symptoms are usually noticed earlier with closed-angle glaucoma. There may be recurrent headaches or heaviness in the eyes in the late afternoon or when in dark places. This may be accompanied by seeing haloes around lights and blurring of vision or even slight eye redness. When the increase in eye pressure is sudden, all the symptoms of eye pain, headache, blurring of vision, and eye redness are more dramatic and severe. The severe pain usually prompts these patients to seek consultation and treatment.

Symptoms include cloudy vision. Sometimes there is glare, and double vision with one eye. Cataracts are usually caused by age. Our natural lens ages and changes in color, as we get older. There are however other causes of cataracts. These include those who have them at birth (congenital), those who develop them in young adulthood (developmental), those acquired from diseases like diabetes mellitus, and those that result as a complication of the intake of some medications like steroids.

halo-590
Haloes around light

 

Some forms of glaucoma have a hereditary factor but not everyone born to a parent with glaucoma would get the disease. However, it is advisable that people with a family history of glaucoma get screened and examined regularly, even in the absence of symptoms, because while there may be no symptoms in the early part of the disease, signs of glaucoma may be detected through a thorough eye examination. As with other diseases, the earlier glaucoma is detected and treated the greater the chances of preserving vision. Therefore, periodic eye examinations on people with a family history of glaucoma especially those over the age of 40 is recommended.

Glaucoma can also be a complication of trauma to the eye, overusing or misusing of steroids, or from inflammatory diseases of the eye.

To test for glaucoma, your pressure of the eye will be determined, the optic nerve will be examined in various ways, and your field of vision will be tested. Your glaucoma eye doctor can discuss the different tests needed.

Treatment of glaucoma would depend on how severe the damage has been, or how fast the disease is progressing. This consists of eye medications in the form of drops, laser to help maintain the pressure within the eye, and if medicines and laser do not prevent further damage, surgery may be needed to create a passageway for the fluid when the pressure is too high. When a patient has glaucoma, regular follow ups with the eye doctor is necessary to check if the disease is progressing or not.

The best way to deal with glaucoma is to prevent progression of damage to vision. However, glaucoma despite all efforts to control the disease can significantly damage sometimes vision. When glaucoma significantly damages vision, one’s activities and lifestyle may be affected. Many people with uncontrolled glaucoma are unable to do what they used to do because of they have been incapacitated by damage to their vision. The degree to which activities and lifestyle can be affected depends on which part they cannot see and the size of the non-seeing part of the visual field. For those who have lost their peripheral vision and can see only what is directly in front of them, crossing the street is a real challenge and driving becomes very dangerous. Many people with glaucoma have lost their jobs because they could no longer read. Depression is common among them too. Fortunately, while it is true that damage to vision caused by glaucoma is irreversible, there is hope for them. While it is true that damage to the visual field due to glaucoma is irreversible and that vision that has been lost cannot be regained, something can be done for them. The answer is maximizing what is left of the vision through visual rehabilitation. A Low Vision Specialist can evaluate these people and help find ways to help them cope with their difficulties.

Diabetic Retinopathy

Diabetic retinopathy is a complication of diabetes when the blood sugar goes up and causes the blood vessels of the retina to break and leak. The damage to the retinal blood vessels may appear as spots in the field of vision.

The blood vessels can get blocked which may cause a lack of oxygen, and this will make the retina swell. This is called the nonproliferative diabetic retinopathy. In the more advanced stages, the lack of oxygen will stimulate the growth of new blood vessels that are very friable and that easily break and bleed. This can cause additional hemorrhage that will decrease vision further. This is the proliferative diabetic retinopathy stage. Sometimes, scar tissue can form which can pull on the retina causing a detachment of the retina. Eventually, if left untreated, diabetic retinopathy can lead to blindness.

People with diabetes must have a regular eye check up. The key to not getting the complication of diabetes is still to maintain the proper blood sugar level. It is essential to have regular visits to their doctor, to maintain good diabetic management.

The treatment for diabetic retinopathy varies depending on the stage. For the nonproliferative stage, if the central portion of the retina or the macula is swollen, laser can be done to help reduce the swelling. In the proliferative stage, laser therapy can be done to prevent the growth of new vessels, and to stop the progress of the retinopathy. If bleeding has occurred in the gel of the eye called the vitreous, removal of the vitreous is done (vitrectomy). However, at this stage, the goal of treatment is not to cure the retinopathy, but to prevent further damage. Despite all these measures the disease can progress to blindness. Early detection and control of diabetes is important. If your vision loss has affected your quality of life, ask for a low vision specialist.

Vision rehabilitation can help people being treated with vision loss from diabetic retinopathy, by devices and solutions that enable them to do the activities they value in daily life.

Cataract

A cataract is an opacity or a clouding of the lens of the eye. It is one of the most common leading causes of visual impairment. This however can be treated by removal of the lens of the eye or cataract extraction, and then replacing the lens removed, with an intraocular lens. Many people suffer from blurred vision due to a cataract and if undetected, glasses or contact lenses cannot improve vision.

Symptoms include cloudy vision. Sometimes there is glare, and double vision with one eye. Cataracts are usually caused by age. Our natural lens ages and changes in color, as we get older. There are however other causes of cataracts. These include those who have them at birth (congenital), those who develop them in young adulthood (developmental), those acquired from diseases like diabetes mellitus, and those that result as a complication of the intake of some medications like steroids.

There is no medical treatment for a cataract. Once it affects your function in daily activities, it would be recommended to remove the lens surgically and replace it with an intraocular lens. Vision may then be restored.

To know more about cataracts and how they are removed, go to American Eye Center’s cataract page

Age-related Macular Degeneration

Age related macular degeneration (AMD) is a degenerative disease of the macula, which is the central portion of the retina. This causes progressive loss of central vision. Since the central vision is the one involved, many of the daily tasks are affected. These include reading, writing, sewing, and the like. Therefore if one has visual disturbances from AMD, the quality of life most likely will deteriorate.

Symptoms are described as having a blurred spot in the central vision, and this usually interferes with tasks that require using their central vision like reading, and writing, and driving. Other symptoms include distortion in the center of the image. Straight lines may appear wavy.

Symptoms include cloudy vision. Sometimes there is glare, and double vision with one eye. Cataracts are usually caused by age. Our natural lens ages and changes in color, as we get older. There are however other causes of cataracts. These include those who have them at birth (congenital), those who develop them in young adulthood (developmental), those acquired from diseases like diabetes mellitus, and those that result as a complication of the intake of some medications like steroids.

If you have been diagnosed with AMD, you are not alone. There are millions of people who have this disease, especially people above the age of 55.

The cause of macular degeneration is unknown but the risk increases with advancing age. Other risk factors are hypertension, smoking, and those with family histories of retinal diseases.

There are two forms of AMD, dry and wet AMD. Dry AMD consists of yellowish deposits called drusen, which accumulate under the central portion of the macula. In wet AMD, abnormal blood vessel growth forms under the central portion of the retina, and it leaks and damages the photoreceptor cells. This can progress rapidly and cause severe damage. But the damage is contained in the patient’s central vision. It can produce a scar, which causes visual impairment that limits the patient to engage in daily activities that require detailed central vision. But even if it may significantly reduce vision, it does not lead to total blindness. Some useable visual function will remain.

There is still no cure for AMD, but there are treatment options that include vitamin supplement for the dry type, and laser treatment or intravitreal injections for the wet type. Your retina specialist can advise you on the best treatment option for you to improve your vision, and to stop your vision loss from progressing. (link to AEC retina page)

Some lifestyle habits have to change like smoking, and diet. Discuss this with your doctor.

If your visual impairment affects your quality of life, then you should ask for consult with a low vision specialist. You can discuss how your vision has affected your quality of life, and the low vision specialist will help you with aids, and services to maximize your residual vision to its fullest potential, and get back to the life you want to lead.