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by Susan H. Gray INNOVATION IN MEDICINE Published in the United States of America by Cherry Lake Publishing Ann Arbor, Michigan www.cherrylakepublishing.com Content Adviser: Noshene Ranjbar, MD Design: The Design Lab Photo Credits: Cover and page 3, ©iStockphoto.com/johncl; page 4, ©Blend Images/Alamy; page 7, ©North Wind Picture Archives/Alamy; page 8, ©Corbis Premium RF/Alamy; page 11, ©INTERFOTO Pressebildagentur/Alamy; page 14, ©iStockphoto.com/davex83; page 15, ©Judy Drietz, used under license from Shutterstock, Inc.; page 17, ©iStockphoto.com/dlewis33; page 18, ©PHOTOTAKE Inc./ Alamy; pages 20 and 21, ©Medical-on-Line/Alamy; page 23, ©PhotoCreate, used under license from Shutterstock, Inc.; page 24, ©Exotic eye/Alamy; page 26, ©Lisa F. Young, used under license from Shutterstock, Inc.; page 27, ©Christine Osborne Pictures/Alamy; page 28, ©Suzanne Porter/Alamy Copyright ©2009 by Cherry Lake Publishing All rights reserved. No part of this book may be reproduced or utilized in any form or by any means without written permission from the publisher. Library of Congress Cataloging-in-Publication Data Gray, Susan H., 1954– Vision / by Susan H. Gray. p. cm.—(Innovation in medicine) Includes index. ISBN-13: 978-1-60279-226-5 ISBN-10: 1-60279-226-7 1. Vision disorders—Treatment—Technological innovations—Juvenile literature. 2. Vision—Juvenile literature. 3. Ophthalmic lenses—History—Juvenile literature. I. Title. II. Series. RE91.G63 2009 617.7—dc22 2008006753 Cherry Lake Publishing would like to acknowledge the work of The Partnership for 21st Century Skills. Please visitwww.21stcenturyskills.org for more information. ChapterOne “The Most Divine Organ” 4 ChapterTwo One Man’s Vision 10 ChapterThree More Innovations 15 Chapter Four A Vision of the Future 20 Chapter Five Innovation for 25 Centuries 23 Glossary 30 For MoreInformation 31 Index 32 About theAuthor 32 INNOVATION IN MEDICINE 4 CHAPTER ONE “Mrs. Jones, you need to write bigger. I can’t see what you wrote on the board!” complained Stephanie. “Are you blind?” shouted Jimmy from the back of the room. “Jimmy! That was rude!” scolded Mrs. Jones. “You should apologize to Stephanie.” Then she turned to Stephanie. “And you need to put on your glasses,” she said with a smile. “But Mrs. Jones, I hate these glasses,” replied Stephanie. “You’re lucky you have eyeglasses to help you see better,” said Mrs. Jones. “Imagine what your life would Many people of all ages wear eyeglasses to be like if you lived a thousand years improve their vision. Vision “The Most Divine Organ” 5 ago, before eyeglasses were invented. Back then, no one knew much about eyes and how they worked.” “Oh no!” groaned Jimmy, rolling his eyes. “I feel a lecture coming on!” The class laughed as Mrs. Jones began telling them more about how eyeglasses were invented. (cid:58)(cid:0)(cid:58)(cid:0)(cid:58) M ore than 1,800 years ago, the Greek doctor Galen studied the human eye. He was impressed with its incredible abilities and called it “the most divine organ.” But he was not the first scientist to examine the remarkable anatomy of the eye. What interested other scientists studying the eye? And what early innovations in medicine did those interests lead to? Susruta was a famed surgeon in India. He described eye operations more than 600 years before Galen lived. He also described a number of surgical instruments and more than 70 different diseases of the eye. Nearsightedness and farsightedness were two eye problems known to the ancients. Those who are nearsighted see only nearby objects clearly. Farsighted people can see faraway objects better. The Roman emperor Nero may have been nearsighted. Some say he held a green crystal up to his eyes to help him see gladiators in combat. INNOVATION IN MEDICINE 6 In the 1200s, a brilliant English monk named Roger Bacon studied physics, math, Latin, and Greek. He wrote of the wonderful qualities of crystals. Bacon described how crystals in nature and human-made glass could help those with poor eyesight. If the glass had a particular shape, he wrote, it could magnify objects. When looking through such glass, “a boy can appear a giant, a man seem a mountain.” So how did innovators use this knowledge of crystals and glass? They invented eyeglasses! People in Europe were using spectacles by the end of the 1200s. About this time, the explorer Marco Polo returned from China and reported that the Chinese were wearing them, too. Spectacles of this time were not worn as they are today. Instead, they consisted of crystals or glass pieces set into metal or leather frames. These frames did not have pieces on the sides that extended to the ears. The spectacles stayed in place by resting on top of the nose and pinching it. Over the next 400 years, the lenses in spectacles did not improve much. The next big advance was the invention of eyeglasses with divided lenses, or bifocals. The top part of the lens helps the wearer see distant objects, and the bottom part helps the wearer see nearby objects. No one is certain who invented bifocals, but many credit American statesman Benjamin Franklin. Franklin Vision 7 Many people believe that Benjamin Franklin invented glasses with divided lenses, or bifocals. told a friend that he was constantly shifting between two pairs of glasses—one for reading and one for seeing in the distance. Tired of having to switch glasses, he wrote, “I had the glasses cut and half of each kind associated in the same circle.” Franklin was pleased because he could now wear one pair of glasses. He simply rolled his eyes up or down to see through the different lenses. The next innovation for improved vision came from Switzerland. In 1888, Adolph Eugen Fick created contact lenses. They were glass with smoothed edges and covered the entire front of the eye. After testing them on himself, Fick wrote that his lenses could sharpen vision. INNOVATION IN MEDICINE 8 He also suggested that people with eyes discolored by disease could benefit from these lenses. He said they could have a colored iris and black pupil painted on each one! Not all of the advances in vision care have been in glasses and contact lenses. Some innovations involved the creation of new instruments to study the eye. Other innovations were in eye surgery. Scientists had been familiar with the anatomy of the eye for centuries. They closely examined the eyes of human beings and animals and identified the parts. The iris is the colored part of the eye. It surrounds a round hole called the pupil. A lens sits just behind the A doctor uses an ophthalmoscope to check her patient’s eyes. Vision
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