by Susan H. Gray I N N O VAT I O N I N M E D I C I N E

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3 by Susan H. Gray INNOVATION IN MEDICINE

4 Published in the United States of America by Cherry Lake Publishing Ann Arbor, Michigan 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: ISBN-10: Vision disorders Treatment Technological innovations Juvenile literature. 2. Vision Juvenile literature. 3. Ophthalmic lenses History Juvenile literature. I. Title. II. Series. RE91.G dc Cherry Lake Publishing would like to acknowledge the work of The Partnership for 21st Century Skills. Please visit for more information.

5 Chapter One The Most Divine Organ 4 Chapter Two One Man s Vision 10 Chapter Three More Innovations 15 Chapter Four A Vision of the Future 20 Chapter Five Innovation for 25 Centuries 23 Glossary 30 For More Information 31 Index 32 About the Author 32 INNOVATION IN MEDICINE

6 4 CHAPTER ONE Many people of all ages wear eyeglasses to improve their vision. 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 be like if you lived a thousand years Vision

7 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. More 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

8 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

9 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

10 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

11 The Most Divine Organ 9 pupil. Watery fluid fills a chamber Learning & Innovation Skills in front of the iris, and a jellylike substance fills the large space behind the lens. The lining at the Can you believe it took back of the eyeball that is sensitive inventors hundreds of to light is called the retina. A years to figure out the large, white optic nerve leads from best way to wear eyeglasses? At one time, the retina to the brain. they attached the frames to a stick that For scientists, it was easy users held up to the face. Inventors tried to study the eyes of animals hooking ribbons to the frames and looping or humans who had died. But the ribbons around the ears. They also learning about the eyes of living tied strings with weights on the end to the patients was almost impossible. eyeglasses and draped the strings over the How could the doctors look inside ears. Finally, in the 1750s, English designer a patient s eye? Everything behind James Ayscough came up with hinged the pupil just looked black. side pieces, which is the basic design we A German doctor solved this use today. Can you think of any ways to problem with a clever invention. improve eyeglasses? Hermann von Helmholtz studied physics, electricity, magnetism, sound, and medicine. He created an instrument that used a lens to direct a beam of light into the eye. When he looked through the same lens, he could see the well-lit interior of the eye. In 1851, he described his invention and called it the ophthalmoscope. Today s eye doctors use an updated version of this instrument. INNOVATION IN MEDICINE

12 10 CHAPTER TWO Throughout history, many people have suffered from cataracts. A cataract is a dull or cloudy spot on the lens of the eye. People often develop them as they age. Severe cases can lead to blindness. In fact, cataracts are the main cause of blindness worldwide. Eye doctors have been aware of this problem since ancient times. To treat it, Susruta, the surgeon of ancient India, performed an operation later called couching. The word couching was used because the doctor forced the clouded lens to lie down as if on a couch. During a couching operation, the doctor and patient sat closely together, facing each other on a bench. The doctor inserted a sharp instrument straight through the pupil and into the patient s lens. The doctor then scooted the lens to the side or downward. In some cases, the Vision

13 One Man s Vision 11 This page from a 16th-century German book shows a doctor carrying out an early operation to treat cataracts. The procedure was called couching. doctor would press the lens back into the jellylike fluid filling the eye. The idea was to move the clouded lens out of the way completely. Then any light entering the pupil would not pass through the lens. INNOVATION IN MEDICINE

14 12 Life & Career Skills After this surgery, a patient had to wear special eyeglasses to make up for the missing lens. Dr. Harold Ridley is best These thick, awkward glasses known for his daring sometimes distorted the patient s new cataract surgery view. Today, couching is still that few believed in at practiced in less-developed first. He was an innovator in other ways, countries. As you might guess, the too. He conducted an important study in outcomes are not always successful. Ghana on the tropical disease called river Fortunately, in 1949, the blindness. This led to a treatment that English ophthalmologist reduces blindness in people living in many Harold Ridley came up with an developing countries today. He also was innovation in the treatment of the first doctor to use television cameras cataracts. A few years after he to record eye operations. This led to the graduated from medical school, use of videos to train new doctors. World War II ( ) broke Learning was a lifelong process for out. Ridley often cared for the Sir Harold Ridley. He was knighted by British soldiers. While tending Queen Elizabeth II in 2000 for his valuable to fighter pilots, he noticed one innovations in ophthalmology and died the thing that puzzled him. Sometimes following year at the age of 94. in battle, small splinters of the acrylic cockpit covers on the planes went into the pilots eyes. But the eye tissue did not swell and become infected, as Ridley expected. In fact, their eye tissue barely reacted at all. Vision

15 One Man s Vision 13 After the war, Ridley continued to work as an ophthalmologist. He knew all about couching and the thick eyeglasses patients had to wear after surgery. He thought there had to be a better way to help those with cataracts. What they really needed were good, clear lenses instead of their cloudy ones. But how could he give them new lenses? Ridley remembered the fighter pilots. If their eyes did not react to acrylic, he thought, maybe cataract sufferers could use acrylic lenses. Maybe he could take out their cloudy lenses and insert new acrylic ones. Other ophthalmologists thought this idea was crazy. Doctors were supposed to remove foreign objects from their patients eyes, they said, not insert them! Nonetheless, in 1949, Ridley asked a company to produce tiny acrylic lenses. Then he performed the world s first cataract surgery. He removed the eye s natural lens and replaced it with the artificial lens. The results were amazing. Over the next couple of years, Ridley repeated the surgery on dozens of people. The vision of almost every patient improved, and the acrylic lenses caused few problems. Ridley continued to do this surgery. Over time, his work improved and got faster. He learned which shapes and sizes of lenses worked best. Eventually, other doctors INNOVATION IN MEDICINE

16 14 accepted Ridley s ideas and began learning how to do the surgery themselves. Today, Ridley s cataract operation is the most common eye surgery performed. It has restored the sight of millions of people. An ophthalmologist performs cataract surgery to replace the patient s cloudy natural lens with an artificial one. Vision

17 15 CHAPTER THREE Throughout the 20th century, ophthalmologists and other researchers have come up with many innovations related to vision. Among these are improved contact lenses and operations to prevent blindness. Today s contact lenses are soft and flexible. Early lenses were large and uncomfortable. INNOVATION IN MEDICINE

18 16 Although contact lenses first appeared in the 1880s, few people wore them until the next century. But as soon as they became popular, patients began complaining about them. Contacts were still so large they covered the entire front of the eye. They also irritated their wearers. These complaints led to many advances. In the 1940s, one inventor came up with small, round, plastic lenses. They were shaped to fit only the cornea. The cornea is the outer layer of the eye that covers the iris and pupil. A few years later, two scientists in what was then Czechoslovakia invented soft lenses. Finally, patients could wear small, comfortable contact lenses. Other doctors were helping their patients with glaucoma. This disease causes people to lose their eyesight slowly. The fluid-filled chamber in front of the iris does not drain well. Too much fluid causes pressure in the eye. This pressure affects the optic nerve, which gradually stops working. The patient s field of view becomes smaller and smaller until it disappears altogether. Robert Stegmann of South Africa wanted to help his glaucoma patients. He knew the fluid-filled chamber normally drains through a very small canal in the eye. But that canal in glaucoma patients becomes plugged. Was there a way, he wondered, to unblock the canal so it could drain properly? Vision

19 More Innovations 17 An ophthalmic technician performs a pressure test on her patient to screen for glaucoma. The instrument directs a quick puff of air into the eye to test for increased pressure. Stegmann inserted a tiny plastic tube into the blocked canal of one of his patients. He slowly fed the tube through the canal, taking great care not to damage any tissues. Then he withdrew the tube. This new procedure was remarkably successful. It forced the canal to open so the fluid could drain. The pressure in the eye decreased, and the field of view stopped shrinking. Now many doctors use this method to help their glaucoma patients. INNOVATION IN MEDICINE

20 18 An ophthalmologist performs corrective laser eye surgery on a patient. A Russian doctor named Svyatoslav Fyodorov was one of the first to do surgery to reshape the cornea. When the cornea has a certain shape, it can act as a lens and sharpen vision. In his surgery, Fyodorov used a sharp instrument to make tiny slices in the cornea. As the Vision