WWW.DISSERTATION.XLIBX.INFO
FREE ELECTRONIC LIBRARY - Dissertations, online materials
 
<< HOME
CONTACTS



Pages:   || 2 |

«Cataract What You Should Know U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health National Eye Institute The National Eye ...»

-- [ Page 1 ] --

Cataract

What You Should Know

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES

National Institutes of Health

National Eye Institute

The National Eye Institute (NEI) conducts and supports

research that leads to sight-saving treatments and plays a

key role in reducing visual impairment and blindness. NEI is

part of the National Institutes of Health, an agency of the

U.S. Department of Health and Human Services.

For more information, contact—

National Eye Institute National Institutes of Health 2020 Vision Place Bethesda, MD 20892–3655 Telephone: 301–496–5248 Email: 2020@nei.nih.gov Website: www.nei.nih.gov Contents About Cataracts 1 Cataract Treatment 6 Questions to Ask Your Eye Care Professional 13 Additional Resources 16 About Cataracts What is a cataract?

A cataract is a clouding of the lens in the eye that affects vision. Most cataracts are related to aging. Cataracts are very common in older people. By age 80, more than half of all Americans have either a cataract or have had cataract surgery.

A cataract can occur in either or both eyes. It cannot spread from one eye to the other.

What is the lens?

The lens is a clear part of the eye that helps to focus light, or an image, on the retina. The retina is the light-sensitive tissue at the back of the eye. (See diagram below.) In a normal eye, light passes through the transparent lens to the retina. Once it reaches the retina, light is changed into nerve signals that are sent to the brain.

The lens must be clear for the retina to receive a sharp image.

If the lens is cloudy from a cataract, the image you see will be blurred.

What causes cataracts?

The lens lies behind the iris and the pupil. It works much like a camera lens. It focuses light onto the retina at the back of the eye, where an image is recorded. The lens also adjusts the eye's focus, letting us see things clearly both up close and far away. The lens is made of mostly water and protein. The protein is arranged in a precise way that keeps the lens clear and lets light pass through it.

But as we age, some of the protein may clump together and start to cloud a small area of the lens. This is a cataract. Over time, the cataract may grow larger and cloud more of the lens, making it harder to see.

Smoking and diabetes contribute to the development of cataract. Or, it may be that the protein in the lens just changes from the wear and tear it takes over the years.

How do cataracts affect vision?

Age-related cataracts can affect vision in two ways:

1. Clumps of protein reduce the sharpness of the image

–  –  –

protein clumps up, it clouds the lens and reduces the light that reaches the retina. The clouding may become severe enough to cause blurred vision. Most age-related cataracts develop from protein clumpings.

When a cataract is small, the cloudiness affects only a small part of the lens. You may not notice any changes in your vision. Cataracts tend to "grow" slowly, so vision gets worse gradually. Over time, the cloudy area in the lens may get larger, and the cataract may increase in size. Seeing may become more difficult. Your vision may get duller or blurrier.

2. The clear lens slowly changes to a yellowish/brownish color, adding a brownish tint to vision.

As the clear lens slowly colors with age, your vision gradually may acquire a brownish shade. At first, the amount of tinting may be small and may not cause a vision problem. Over time, the cataract usually increases in size.

This gradual change in the amount of tinting does not affect the sharpness of the image transmitted to the retina.

If you have advanced lens discoloration, you may not be able to identify blues and purples. You may be wearing what you believe to be a pair of black socks, only to find out from friends that you are wearing purple socks.

When are you most likely to have a cataract?

The term "age-related" is a little misleading. You don't have to be a senior citizen to get this type of cataract. In fact, people can have an age-related cataract in their 40s and 50s. But during middle age, most cataracts are small and do not affect vision. It is after age 60 that most cataracts cause problems with a person's vision.

Who is at risk for cataract?

The risk of cataract increases as you get older. Other risk

factors for cataract include:

• Certain diseases (for example, diabetes).

• Personal behavior (smoking, alcohol use).

• The environment (prolonged exposure to ultraviolet sunlight).

What are the symptoms of a cataract?

The most common symptoms of a cataract are:

• Cloudy or blurry vision.

–  –  –

• Frequent prescription changes in your eyeglasses or contact lenses.

These symptoms also can be a sign of other eye problems. If you have any of these symptoms, check with your eye care professional.

Are there different types of cataract?

Yes. Although most cataracts are related to aging, there are

other types of cataract:

• Secondary cataract. Cataracts can form after surgery for other eye problems, such as glaucoma. Cataracts also can develop in people who have other health problems, such as diabetes. Cataracts are sometimes linked to steroid use.





• Traumatic cataract. Cataracts can develop after an eye injury, sometimes years later.

• Congenital cataract. Some babies are born with cataracts or develop them in childhood, often in both eyes. These cataracts may be so small that they do not affect vision. If they do, the lenses may need to be removed.

• Radiation cataract. Cataracts can develop after exposure to some types of radiation.

How is a cataract detected?

Cataract is detected through a comprehensive eye exam that

includes:

• Visual acuity test. This eye chart test measures how well you see at various distances.

• Dilated eye exam. Drops are placed in your eyes to widen, or dilate, the pupils. Your eye care professional uses a special magnifying lens to examine your retina and optic nerve for signs of damage and other eye problems. After the exam, your close-up vision may remain blurred for several hours.

• Tonometry. An instrument measures the pressure inside the eye. Numbing drops may be applied to your eye for this test.

Your eye care professional also may do other tests to learn more about the structure and health of your eye.

–  –  –

magnifying lenses. If these measures do not help, surgery is the only effective treatment. Surgery involves removing the cloudy lens and replacing it with an artificial lens.

A cataract needs to be removed only when vision loss interferes with your everyday activities, such as driving, reading, or watching TV. You and your eye care professional can make this decision together. Once you understand the benefits and risks of surgery, you can make an informed decision about whether cataract surgery is right for you. In most cases, delaying cataract surgery will not cause long-term damage to your eye or make the surgery more difficult. You do not have to rush into surgery.

Sometimes a cataract should be removed even if it does not cause problems with your vision. For example, a cataract should be removed if it prevents examination or treatment of another eye problem, such as age-related macular degeneration or diabetic retinopathy.

If you choose surgery, your eye care professional may refer you to a specialist to remove the cataract.

If you have cataracts in both eyes that require surgery, the surgery will be performed on each eye at separate times, usually four weeks apart.

Is cataract surgery effective?

Cataract removal is one of the most common operations performed in the United States. It also is one of the safest and most effective types of surgery. In about 90 percent of cases, people who have cataract surgery have better vision afterward.

What are the risks of cataract surgery?

As with any surgery, cataract surgery poses risks, such as infection and bleeding. Before cataract surgery, your doctor may ask you to temporarily stop taking certain medications that increase the risk of bleeding during surgery. After surgery, you must keep your eye clean, wash your hands before touching your eye, and use the prescribed medications to help minimize the risk of infection. Serious infection can result in loss of vision.

Cataract surgery slightly increases your risk of retinal detachment. Other eye disorders, such as high myopia (nearsightedness), can further increase your risk of retinal detachment after cataract surgery. One sign of a retinal detachment is a sudden increase in flashes or floaters. Floaters are little “cobwebs” or specks that seem to float about in your field of vision. If you notice a sudden increase in floaters or flashes, see an eye care professional immediately. A retinal detachment is a medical emergency. If necessary, go to an emergency service or hospital. Your eye must be examined by a physician as soon as possible. A retinal detachment causes no pain. Early treatment for retinal detachment often can prevent permanent loss of vision. The longer the retina stays detached, the less likely you will regain good vision once you are treated. Even if you are treated promptly, some vision may be lost.

–  –  –

Talk to your eye care professional about these risks. Make sure cataract surgery is right for you.

What if I have other eye conditions and need cataract surgery?

Many people who need cataract surgery also have other eye conditions, such as age-related macular degeneration or glaucoma. If you have other eye conditions in addition to cataract, talk with your doctor. Learn about the risks, benefits, alternatives, and expected results of cataract surgery.

What happens before surgery?

A week or two before surgery, your doctor will do some tests.

These tests may include measuring the curve of the cornea and the size and shape of your eye. This information helps your doctor choose the right type of IOL.

You may be asked not to eat or drink anything 12 hours before your surgery.

What happens during surgery?

At the hospital or eye clinic, drops will be put into your eye to dilate the pupil. The area around your eye will be washed and cleansed.

The operation usually lasts less than one hour and is almost painless. Many people choose to stay awake during surgery.

Others may need to be put to sleep for a short time. If you are awake, you will have an anesthetic to numb your eye.

After the operation, a patch may be placed over your eye.

You will rest for a while. Your medical team will watch for any problems, such as bleeding. Most people who have cataract surgery can go home the same day. You will need someone to drive you home.

What happens after surgery?

Itching and mild discomfort are normal after cataract surgery. Some fluid discharge is also common. Your eye may be sensitive to light and touch. If you have discomfort, your doctor can suggest treatment. After one or two days, moderate discomfort should disappear.

For a few weeks after surgery, your doctor may ask you to use eyedrops to help healing and decrease the risk of infection.

Ask your doctor about how to use your eyedrops, how often to use them, and what effects they can have. You will need to wear an eye shield or eyeglasses to help protect your eye.

Avoid rubbing or pressing on your eye.

When you are home, try not to bend from the waist to pick up objects on the floor. Do not lift any heavy objects. You can walk, climb stairs, and do light household chores.

In most cases, healing will be complete within eight weeks.

Your doctor will schedule exams to check on your progress.

–  –  –

eye pressure. With prompt medical attention, these problems usually can be treated successfully.

Sometimes the eye tissue that encloses the IOL becomes cloudy and may blur your vision. This condition is called an aftercataract. An after-cataract can develop months or years after cataract surgery.

An after-cataract is treated with a laser. Your doctor uses a laser to make a tiny hole in the eye tissue behind the lens to let light pass through. This outpatient procedure is called a YAG laser capsulotomy. It is painless and rarely results in increased eye pressure or other eye problems. As a precaution, your doctor may give you eyedrops to lower your eye pressure before or after the procedure.

When will my vision be normal again?

You can return quickly to many everyday activities, but your vision may be blurry. The healing eye needs time to adjust so that it can focus properly with the other eye, especially if the other eye has a cataract. Ask your doctor when you can resume driving.

If you received an IOL, you may notice that colors are very bright. Most IOLs are clear, unlike your natural lens that may have had a yellowish/brownish tint. Within a few months after receiving an IOL, you will become used to improved color vision. Also, when your eye heals, you will most likely need new glasses or contact lenses.

What can I do if I already have lost some vision from cataract?

If you have lost some vision, speak with your surgeon about options that may help you make the most of your remaining vision.

What research is being done?

The National Eye Institute is conducting and supporting a number of studies focusing on factors associated with the

development of age-related cataract. These studies include:

• The effect of sunlight exposure, which may be associated with an increased risk of cataract.

• Vitamin supplements, which have shown varying results in delaying the progression of cataract.

• Genetic studies, which show promise for better understanding cataract development.

What can I do to protect my vision?

Wearing sunglasses and a hat with a brim to block ultraviolet sunlight may help to delay cataract. If you smoke, stop.



Pages:   || 2 |


Similar works:

«Basic Plan Preferred Provider Organization Evidence of Coverage Effective January 1, 2016 – December 31, 2016 A Self-Funded Plan Administered Under the Public Employees’ Medical & Hospital Care Act (PEMHCA) HOW TO REACH US Important: For all members outside of the United States, contact the operator in the country you are in to assist you in making a toll-free number call.CUSTOMER SERVICE For information regarding Protected Health Information: For medical claims status, claim forms,...»

«Q+AWorking hours What does the Working Hours Act cover? The Working Hours Act (ATW) describes how long you are allowed to work per day and per week and when you are entitled to a break or rest period. The rules have been made for the sake of your health, safety and welfare, but also to make it easier for you to combine your work, private life and care obligations. The rules apply to employees aged 18 years and older. Separate rules apply to children aged under 16 and for young people aged 16...»

«Director of Infection Prevention and Control (DIPC) Annual Report April 2009 to March 2010 Laying the Foundations – the first DIPC annual report for Dudley and Walsall Mental Health NHS Partnership Trust Alison Geeson – Head of Nursing Author: Wendy Pugh – Director of Operations and Prepared On Behalf Of: Nursing/Director of Infection Prevention and Control Date: June 2010 DIPC Annual Report 2009-10 (Final) – June 2010 Page 1 of 40 Contents Section Page Number List of Abbreviations 3...»

«A Guide to Effective Consultation with Settings Serving Infants, Toddlers, and their Families Core Knowledge, Competencies, and Dispositions Sponsored by: U.S. Department of Health and Human Services Administration for Children and Families OFFICE OF HEAD START DEPARTMENT OF HEALTH & HUMAN SERVICES Administration for Children and Families Dear Early Care and Education Colleagues: On behalf of the Administration for Children and Families (ACF), U.S. Department of Health and Human Services (HHS),...»

«integrated flood management tools series health and sanitation aspects of flood management ISSUE 23 INTEGRATED FLOOD MANAGEMENT TOOL SERIES | A DECEMBER 2015 The Associated Programme on Flood Management (APFM) is a joint initiative of the World Meteorological Organization (WMO) and the Global Water Partnership (GWP). It promotes the concept of Integrated Flood Management (IFM) as a new approach to flood management. The programme is financially supported by the Federal Office for the Environment...»

«Health Literate Discharge Practices in Ontario Hospitals by Jennifer Anne Innis A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Institute of Health Policy, Management and Evaluation University of Toronto © Copyright by Jennifer Anne Innis 2016 Health Literate Discharge Practices in Ontario Hospitals Jennifer Anne Innis Doctor of Philosophy Institute of Health Policy, Management and Evaluation University of Toronto Abstract Health literate discharge...»

«The Breeder’s Puppy Plan INTRODUCTION Why Do We Need The Puppy Plan? From the moment a litter of puppies is planned, both the breeder, and then later the new owner, want to do everything possible to make sure that each new puppy has the chance to grow up to realise his or her full potential. Thanks to the advances in health testing for both the puppy's parents and later themselves, coupled with responsible breeding, we can do much to make sure puppies are physically healthy and ‘fit for...»

«The framing of social class distinctions through family food and eating practices Wills, W.J., Backett-Milburn, K., Roberts, E.M. and Lawton, J. Abstract Drawing on two qualitative studies which looked at diet, weight and health from a social class perspective, we use Bourdieu’s theory of habitus to help explain the different food and eating practices undertaken by families with young teenagers. Whilst the families displayed considerable reflexivity when making decisions about what to eat on...»

«BASIC DOCUMENTS Forty-seventh Edition Basic Documents appears in new editions as necessary. WHO official documentation, including basic documents, is accessible electronically through the Governance pages on the WHO web site (http://www.who.int/ governance/): click on Basic Documents (right-hand column). BASIC DOCUMENTS Forty-seventh Edition Including amendments adopted up to 31 May 2009 ii BASIC DOCUMENTS WHO Library Cataloguing in Publication Data World Health Organization Basic documents....»

«Consideration of Discussion Paper on the Regulation of Autologous Stem Cell Therapies Dr Kevin A Boundy – Regenexx Australia [Type text] Table of Contents General Discussion Introduction Safety Efficacy Public Health Risks Costs Executive summary Recommendations Answers to Discussion Questions What are the public health risks of ‘autologous stem cells’ in your view? What is the evidence for these risks? What identified risks should have the highest priority for resolving? What do you see...»

«10 Poverty, social exclusion, and minorities Mary Shaw, Danny Dorling and George Davey Smith 10.1 Introduction Poverty, the extent of relative deprivation, and the processes of social exclusion in a society have a major impact on the health of its population. All over Europe, in richer countries as well as poorer ones, those people who are worse off in socio-economic terms have worse health outcomes and higher death rates than those who are better off. Particular ‘minority’ ethnic groups...»

«Partnerships for Health System Improvement (PHSI) Leadership and Health System Redesign Prairie Node Case Study Final Report Gregory P. Marchildon Canada Research Chair and Professor Johnson-Shoyama Graduate School of Public Policy University of Regina Donald Philippon Professor Emeritus School of Public Health University of Alberta Amber Fletcher Post-doctoral Research Fellow Johnson-Shoyama Graduate School of Public Policy University of Regina December 2013 Table of Contents Executive...»





 
<<  HOME   |    CONTACTS
2016 www.dissertation.xlibx.info - Dissertations, online materials

Materials of this site are available for review, all rights belong to their respective owners.
If you do not agree with the fact that your material is placed on this site, please, email us, we will within 1-2 business days delete him.