Ординатура / Офтальмология / Английские материалы / The Eye Book A Complete Guide to Eye Disorders and Health_Cassel, Billig, Randall_2001

18.1. Nonproliferative Diabetic Retinopathy 424

18.2.Intraretinal Microvascular Abnormalities (IRMA) 424

18.3.Macular Edema 425

18.4. Proliferative Diabetic Retinopathy 427

Foreword

As the consumerism movement has flourished in the United States, so too has the need increased for more personal participation in health care decisions. Individual responsibility for understanding one’s own health is an obvious component of this process. Numerous selfhelp periodicals and books have appeared to meet the growing demands of the public for health information of all kinds.

Drs. Cassel and Randall, experienced community ophthalmologists and part-time faculty members of the Wilmer Eye Institute at Johns Hopkins, along with their respected colleague, Dr. Billig, now publish The Eye Book: A Complete Guide to Eye Disorders and Health within this educational framework. It is an exceptionally useful book for the public because it dispels myths and offers practical guidelines in a very readable style. It covers the routine (for example, eyeglasses) and the serious (for example, macular degeneration). The authors are appro-

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priately cautious about recommending new, but unproven, treatments.

We are entering a golden age of knowledge about heretofore perplexing and sometimes blinding diseases, and futuristic techniques, ranging from optoelectronics to genetic engineering, promise bright prospects for our aging population. Medical and scientific institutions such as the Wilmer Institute at Johns Hopkins are actively continuing the search for better treatment techniques; simultaneously, they continue their dedication to the clinical care of routine and complex eye disease as well as to the education of doctors and researchers—and the general public. For the good health of your own eyes and vision, I encourage you to read and consult this helpful book for information, and to seek the assistance of highly experienced eye care specialists for diagnosis and treatment.

Morton F. Goldberg, . ., . . . .

Director, Wilmer Eye Institute

The Johns Hopkins Medical Institutions

Baltimore, Maryland

Preface

The eye, responsible for one of our most vital senses, is one of the most important organs in the body. When all is well, most of us take our eyes for granted. But as you no doubt know from experience, when your vision is blurred, or your eyes are itchy and watery, or it feels like there’s something “sticking” in there, it’s hard to concentrate on anything but your eyes. When something’s not right with your eyes, then nothing’s right with the world. As eye care specialists, we devote our working hours to helping people with eye problems of all kinds. And we have written this book to help the many people who have such problems, or who are worried about their eyes or the eyes of someone they care about.

It’s remarkable and humbling to consider how far the field of ophthalmology—the medical specialty covering the anatomy, functions, pathology, and treatment of the eye—has progressed over the last three decades, a period when we have seen our patients helped by innovations

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in every aspect of eye care that were unheard of only a short time ago. New antibiotics and medications, safer cataract surgery with shorter recovery time, better glaucoma treatments, refined surgical techniques for mending retinal detachments and clearing vitreous hemorrhages, and retinovitreous treatments—not to mention a revolution in lens-making materials and technology— have helped thousands of people to see better longer.

In this book we describe all of these recent innovations and offer information and advice about what you and your eye doctor can do together to safeguard your vision, and your general health. We describe the eye’s anatomy and what changes occur naturally over time, as well as what changes are not natural and may be dan- gerous—and tell you what to do about them. We demystify the eye examination, describe how eyeglasses and contact lenses work (and how to tell what will work best for you), and take up the controversial vision-corrective surgery called refractive surgery.

Cataracts, glaucoma, and age-related macular degeneration are the three major diseases of the eye that rob older people of good vision. Knowing the signs and symptoms of these diseases and how to get proper checkups and screening are crucial first steps; once the diagnosis is made, treatment options must be weighed and decisions made. The three chapters in the second part of the book discuss each of these problems in detail.

In part 4 of the book we continue the discussion of eye problems, beginning from the front of the eye, at the lids and lashes, and ending up at the back, with the optic

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nerve. Explanations of problems ranging from the annoying (“floaters and flashes,” for example, or a twitching eyelid) to the more serious (uveitis, or arthritis of the eye) may be found here.

In the final section of the book we have collected chapters on topics that are important for anyone wishing to have a better understanding of what happens to our eyes as we age. Eye trauma and emergencies are discussed so that readers will be able to take better care of their eyes and know how to recognize an eye emergency and what to do. A thorough explanation of how such diseases as diabetes, high blood pressure, and migraine headaches affect the eyes should be helpful to anyone coping with these problems. A chapter on low vision describes helpful devices and services and offers useful tips for people with declining visual acuity. Our final chapter looks at how common medications like antibiotics and blood pressure medications can affect the eyes, while in an appendix we describe the side effects of specific eye medications.

This book is designed to offer reliable and current information. We hope that it will help you understand your own eyes, your vision, and any problems you may be having. If you are facing a decision about eye treatment, you may want to take this book with you to your doctor’s office, to discuss information that you find useful. As helpful as we hope this book will be, however, we know that only you and your doctor can make decisions about your treatment, based on your specific situation.

Finally, as in other aspects of life, many myths have

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sprung up around the area of vision, and they have been passed on from generation to generation, causing confusion and sometimes fear. Before turning to part 1, let’s explore some of these bits of accepted wisdom as good examples of the bad information we hope to replace with this book.

Vision Myths

Reading in dim light can hurt your eyes.

Picture Anne Sullivan, the dedicated, selfless teacher of Helen Keller, night after endless night, reading in halflight, straining her own eyes to the breaking point. Makes you wish for indoor flood lamps, doesn’t it? And yet, although inadequate light can cause temporary eye fatigue, it can’t permanently damage your eyes. If it could, Abe Lincoln, who studied by candlelight—as did every scholar in the centuries before Edison—would have had poor vision. But why do it? Everyone ought to use good lighting—especially as we get older, when cataracts and other problems can dim our vision. Also, good lighting always makes it easier for your eyes to focus on what you are reading and helps to lessen fatigue.

Eye exercises can improve vision.

Sadly, for almost all of us, this one isn’t true either. There are muscles in the eye, but they don’t “shape up” like a flabby belly on a regimen of sit-ups. Only a small percentage of eye problems respond to eye exercises.

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Also, eye exercises can’t prevent you from ever needing eyeglasses. Note: If an eye doctor recommends a course of eye exercises for you, please seek a second opinion; these ocular workouts are useful in some circumstances, but they have their limitations.

Wearing the right sunglasses can prevent cataracts.

Many products—natural foods, herbal medicines, expensive lens coatings, special eye drops, high-tech sun- glasses—have been marketed as means of preventing cataracts, and there’s some science to back this up: ultraviolet toxicity can harm the eyes, but not nearly as commonly or easily as sunlight damages the skin and causes skin cancer. But we also have to note that most people have some cataract development as they get older. In some people, cataracts develop quickly and need treatment; in others, they don’t. Thus—because the sheer numbers are so great—statistically, any product that claims to prevent, or at least slow, cataract development will appear to work fairly often. Do they really? Probably not.

It’s entirely reasonable to ask what practical steps can be taken to prevent your vision from deteriorating, but the bottom line is that many eye problems are simply the luck of the genetic draw. For example, myopia, like heart disease, has a major genetic component. If your family reunion looks like a LensCrafters commercial, then you probably ought to resign yourself to the fact that myopia runs in your family. But there are some things you can do: Try to avoid injuries. Take care of your general

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health—especially if you have diabetes or high blood pressure. And get regular eye exams throughout your life. Many eye problems are highly treatable, but only if they are caught in time.

Eating carrots helps you see better (so rabbits must see great).

Carrots are rich in vitamin A, which is indeed important for eyesight. But carrots haven’t cornered the market on vitamin A; many other foods—green vegetables and yellow squash, for instance—are also rich in it. And we don’t need that much Vitamin A, anyway; a well-bal- anced diet, with or without carrots, provides all the nutrients we need for good vision.

However, severe lack of vitamins A, C, and E—a problem often found in people living in underdeveloped countries—can lead to serious eye disease. And one recent study has also suggested that macular degeneration, a common cause of visual difficulty in many older people, may be due to another dietary deficiency: a lack of trace metals (such as zinc). The message here: Take your vitamins in reasonable doses (not megadoses). Take one multivitamin daily. And eat your vegetables.

Sitting in front of a computer screen for hours on end can damage your eyes.

Well, it sure doesn’t do them any good, but fortunately the eyestrain and fatigue caused by overuse of computers and video display terminals (VDTs) is only temporary. Eyestrain and fatigue can be unwelcome by-prod-