After the war Kolff moved to the United States, where he continued to work on bionic engineering problems. At the Cleveland Clinic he encouraged Tetsuzo Akutsu to design a prototype artificial heart. Together they created the first concept for a practical artificial heart. To others it seemed like an impossible challenge, but to Kolff the issue was simple: "If man can grow a heart, he can build one," he once declared. These first efforts, beginning in the late 1950s, did little more than eliminate fruitless lines of research. Later, as a professor of surgery and bioengineering at the University of Utah, Kolff formed a team that included physician-inventor Robert Jarvik and surgeon William DeVries. After 15 difficult years of invention and experimentation, DeVries implanted one of Jarvik's hearts—a silicone and rubber unit powered by compressed air from an external pump—in Barney Clark, who survived for 112 days. Negative press about Clark's condition during his final days slowed further progress for a while, but today more sophisticated versions of artificial hearts and ventricular-assist devices, including self-contained units that allow greater patient mobility, routinely serve as temporary substitutes while patients await heart transplants. After the war Kolff moved to the United States, where he continued to work on bionic engineering problems. At the Cleveland Clinic he encouraged Tetsuzo Akutsu to design a prototype artificial heart. Together they created the first concept for a practical artificial heart. To others it seemed like an impossible challenge, but to Kolff the issue was simple: "If man can grow a heart, he can build one," he once declared. These first efforts, beginning in the late 1950s, did little more than eliminate fruitless lines of research. Later, as a professor of surgery and bioengineering at the University of Utah, Kolff formed a team that included physician-inventor Robert Jarvik and surgeon William DeVries. After 15 difficult years of invention and experimentation, DeVries implanted one of Jarvik's hearts—a silicone and rubber unit powered by compressed air from an external pump—in Barney Clark, who survived for 112 days. Negative press about Clark's condition during his final days slowed further progress for a while, but today more sophisticated versions of artificial hearts and ventricular-assist devices, including self-contained units that allow greater patient mobility, routinely serve as temporary substitutes while patients await heart transplants. Kolff was not done. With his colleagues he helped improve the prosthetic arm—another major life-improving triumph of "spare parts" medicine—as well as contributing to the development of both an artificial eye and an artificial ear. Progress in all these efforts has depended on advancements in a number of engineering fields, including computers, electronics, and high performance materials. Computers and microelectronic components, for example, have made it possible for bioengineers to design and build prosthetic limbs that better replicate the mechanical actions of natural arms and legs. And first-generation biomaterials—polymers, metals, and acrylic fibers among others—have been used for almost everything from artificial heart valves and eye lenses to replacement hip, knee, elbow, and shoulder joints.
Engineering processes have had an even broader effect on the practice of medicine. The 20th century's string of victories over microbial diseases resulted from the discovery and creation of new drugs and vaccines, such as the polio vaccine and the whole array of antibiotics. Engineering approaches—including manufacturing techniques and systems design—played significant roles in both the development of these medications and their wide availability to the many people around the world who need them. For example, engineers are involved in designing processes for chemical synthesis of medicines and building such devices as bioreactors to "grow" vaccines. And assembly line know-how, another product of the engineering mind, is crucial to the mixing, shaping, packaging, and delivering of drugs in their myriad forms. Engineering processes have had an even broader effect on the practice of medicine. The 20th century's string of victories over microbial diseases resulted from the discovery and creation of new drugs and vaccines, such as the polio vaccine and the whole array of antibiotics. Engineering approaches—including manufacturing techniques and systems design—played significant roles in both the development of these medications and their wide availability to the many people around the world who need them. For example, engineers are involved in designing processes for chemical synthesis of medicines and building such devices as bioreactors to "grow" vaccines. And assembly line know-how, another product of the engineering mind, is crucial to the mixing, shaping, packaging, and delivering of drugs in their myriad forms. It may be in the operating room rather than the pharmaceutical factory, however, that engineering has had a more obvious impact. A number of systems have increased the surgeon's operating capacity, especially during the last half of the century. One of the first was the operating microscope, invented by the German company Zeiss in the early 1950s. By giving surgeons a magnified view, the operating microscope made it possible to perform all manner of intricate procedures, from delicate operations on the eye and the small bones of the inner ear to the reconnection of nerves and even the tiniest blood vessels—a skill that has enabled more effective skin grafting as well as the reattachment of severed limbs.
At about the same time as the invention of the operating microscope, a British researcher named Harold Hopkins helped perfect two devices that further revolutionized surgeons' work: the fiber-optic endoscope and the laparoscope. Both are hollow tubes containing a fiber-optic cable that allows doctors to see and work inside the body without opening it up. Endoscopes, which are flexible, can be fed into internal organs such as the stomach or intestines without an incision and are designed to look for growths and other anomalies. Laparoscopes are rigid and require a small incision, but because they are stiff, they enable the surgeon to remove or repair internal tissues by manipulating tiny blades, scissors, or other surgical tools attached to the end of the laparoscope or fed through it.
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