4
From the Scalpel to the Scope: Endoscopic Innovations in Gastroenterology, Gynecology, and Surgery

ANNETINE C. GELIJNS AND NATHAN ROSENBERG

Minimally invasive therapy is an extremely dynamic area of innovation, as illustrated by the establishment of new professional journals1 and societies, the growing number of publications in established journals as well as the lay press, and the rapid entry of medical device firms into the market. Generally, the term innovation—newness in its most literal sense—conveys an image of step-by-step reduction to practice of a major new scientific or engineering observation, which then generates a breakthrough technology. As the history of minimally invasive therapy shows us, however, the nature of the innovation process is much more incremental than this image suggests and, moreover, often involves the fusion of a wide range of existing technological capabilities (Kodama, 1992). Indeed, we regard as a key feature of medical innovation, and perhaps even the key feature, the manner in which disciplinary and organizational boundaries are crossed.

The central technological component in minimally invasive therapy is the endoscope: a slender rigid or flexible tube through which images can be transmitted, either to the eyepiece or, nowadays mostly, onto a videoscreen. A variety of accessory technologies, such as miniaturized forceps, electrocautery devices, and lasers, can then be moved through the operative channel of the endoscope, or through an alternative instrument inserted in the human body, to undertake the necessary therapeutic interventions.

1  

A sample of new journals includes the Journal of Laparoscopic Surgery (begun in 1990), The Journal of Laparoendoscopic Surgery (1991), Surgical Laparoscopy & Endoscopy (1991), The Journal of Lithotripsy & Stone Disease (1989), and The Journal of Interventional Cardiology.



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Sources of Medical Technology: Universities and Industry 4 From the Scalpel to the Scope: Endoscopic Innovations in Gastroenterology, Gynecology, and Surgery ANNETINE C. GELIJNS AND NATHAN ROSENBERG Minimally invasive therapy is an extremely dynamic area of innovation, as illustrated by the establishment of new professional journals1 and societies, the growing number of publications in established journals as well as the lay press, and the rapid entry of medical device firms into the market. Generally, the term innovation—newness in its most literal sense—conveys an image of step-by-step reduction to practice of a major new scientific or engineering observation, which then generates a breakthrough technology. As the history of minimally invasive therapy shows us, however, the nature of the innovation process is much more incremental than this image suggests and, moreover, often involves the fusion of a wide range of existing technological capabilities (Kodama, 1992). Indeed, we regard as a key feature of medical innovation, and perhaps even the key feature, the manner in which disciplinary and organizational boundaries are crossed. The central technological component in minimally invasive therapy is the endoscope: a slender rigid or flexible tube through which images can be transmitted, either to the eyepiece or, nowadays mostly, onto a videoscreen. A variety of accessory technologies, such as miniaturized forceps, electrocautery devices, and lasers, can then be moved through the operative channel of the endoscope, or through an alternative instrument inserted in the human body, to undertake the necessary therapeutic interventions. 1   A sample of new journals includes the Journal of Laparoscopic Surgery (begun in 1990), The Journal of Laparoendoscopic Surgery (1991), Surgical Laparoscopy & Endoscopy (1991), The Journal of Lithotripsy & Stone Disease (1989), and The Journal of Interventional Cardiology.

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Sources of Medical Technology: Universities and Industry In the environment of resource and cost constraint in health services that emerged during the 1980s, an uncommon consensus among patients, physicians, providers, and payers evolved regarding the rapid acceptance of this area of medical intervention, an acceptance that, in turn, has been stimulating further innovation. Minimally invasive therapy may obviate the need for major open-surgery procedures. In terms of health outcomes, it appears to offer the following advantages: elimination of the need for general anesthesia, the absence of the sequelae of open surgery procedures, minute scars, short hospital stays or outpatient treatment, and a much more rapid return to normal activity. Clearly, reductions in length of hospitalization and the ability to return to work much sooner can be regarded as attractive economic features as well. Although the current very rapid rate of diffusion and the often inadequate levels of training of clinicians in these new procedures are increasing complication rates and raising some reservations about this revolution in surgical care, minimally invasive therapy per se appears to promise important medical and economic benefits. Yet the history of minimally invasive therapy is a long one, and—as we shall see—these benefits were not always as obvious or important as they are nowadays. The therapeutic use of endoscopes was preceded by their diagnostic use. In fact, since the Middle Ages, physicians had had the idea that a tube containing lenses and mirrors could be used to look into the natural orifices of the human body to obtain diagnostic information (Filipi et al., 1991). Despite these concepts and intense human curiosity, the possibility of examining the internal workings of a living body long defied human ingenuity. Natural orifices that might constitute points of entry are few. Lens systems were still unsophisticated and the only source of illumination was provided by candles or a platinum wire heated to brilliance by an electric current.2 Even with an appropriate light source, a rigid instrument could provide little or only limited opportunity for informative inspection of certain organs, such as the digestive tract. The development of a flexible endoscope was especially beset by difficulties. Plastics were not available in the nineteenth century, and although the vulcanization of rubber, which offered a material that was strong as well as flexible, was accomplished by 1839, the major obstacle remained: finding ways to make glass lens systems flexible. Nevertheless, important advances were made in the closing decades of the nineteenth century: a critical step was Edison's discovery of the incandescent light bulb, which in miniaturized form could be mounted to the distal tip of the endoscope, and Nitze's introduction of a dramatically improved lens system. As 2   In view of the primitive nature of lighting technology before the discovery of the incandescent source, the disapproval of the authorities toward attempts at visualization may not have been entirely inappropriate. As Gaskin et al. (1991) observed: "The first attempt at endoscopy was by Bozzini in 1805. He was censored by the medical faculty of Vienna for being too inquisitive in attempting to observe the interior of the urethra in a living patient with a simple tube and candlelight" (p. 1086).

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Sources of Medical Technology: Universities and Industry a result, cystoscopy—which involved inserting a rigid endoscope into the urethra—became a fairly well-established procedure at this time. Around the turn of the century, efforts to develop and manufacture these endoscopes were concentrated in Germany, a concentration that was presumably closely linked to German technical skills in the design and manufacture of instrumentation generally, and perhaps optical instruments in particular. We should not underestimate, however, the immense gap between the performance of these first devices and the performance characteristics needed for more widespread adoption. For example, the lamp at the tip of the endoscope could cause serious burns, vision often was restricted, the quality of images was poor, and obtaining some form of permanent documentation of the images was highly problematic, at best. The more widespread application of endoscopic procedures required major improvements in lighting, optics, and photographic capabilities. This meant that the evolution of endoscopic techniques was essentially interdisciplinary and interinstitutional in nature; that is, it required the medical profession to create alliances with scientists and engineers with expertise in optics, electronics, and—more recently—optoelectronics. These interactions between clinicians, often in academic medical centers, and technologists, often in industrial firms, are important for the development of first-generation devices. Yet in medicine, where research and development (R&D) and adoption are closely linked, the rate and direction of the subsequent improvement process is also likely to be influenced by the experience of the early users3 and by the effectiveness with which this information is fed back to the device manufacturers. Given these characteristics, our emphasis in this chapter will be on the following question: What can the history of endoscopy tell us about the circumstances surrounding, and more specifically the barriers to, innovation that requires the crossing of disciplinary as well as institutional boundaries? Before turning to the task at hand, one final point deserves mentioning. This chapter takes a historical approach in that it covers roughly half a century of innovation in endoscopy. Clearly, during this time period the economic, social, and regulatory environment within which R&D efforts have taken place underwent considerable change. Consider, for example, the economic environment. Since World War II the incentive signals from the U.S. health care financing system to the R&D sector have been to enhance quality of care regardless of costs; it is only over the past decade—with the introduction of the prospective payment system for Medicare and all kinds of managed care initiatives—that 3   In medicine, the term user requires some clarification. Although one could argue that patients are the ultimate beneficiaries and users of technologies, patients for a variety of reasons traditionally have delegated decisions about the kinds and levels of technological intervention they need to their physicians. As a result, physicians have been considered the principal users insofar as the generators of new technologies are concerned.

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Sources of Medical Technology: Universities and Industry these signals have been changing toward more emphasis on containing costs. Whereas we explore how some of these changes in the broader environment have influenced and shaped the conditions surrounding medical R&D in the past, the current changes in the incentive environments remains an important topic for further exploration. FIBER OPTICS AND GASTROINTESTINAL ENDOSCOPY Beginning in the 1920s, the field of gastrointestinal endoscopy in Europe and the United States was dominated by a single individual, Rudolf Schindler. Schindler, a German doctor born in Berlin in 1888, undertook hundreds of examinations with rigid gastroscopes and published his findings in a major work, Lehrbuch und Atlas der Gastroskopie, in 1923. He subsequently introduced a semiflexible gastroscope in 1932. His work over the next 30 years pushed the subject to what were probably the ultimate limits attainable, given the tools and materials that were available before the 1960s. The so-called Wolf-Schindler semiflexible gastroscope was "an acceptably safe, workable instrument capable of conveying informative images of the stomach's interior to the eye of the examining physician" (Haubrich, 1987, p. 6). It is clear that Schindler relied heavily upon the skills and earlier industrial experience of George Wolf, a Berlin instrument maker. Interestingly enough, Wolf had previously devised a prototype optical instrument to be used in inspecting the condensing tubes in steam engines. His acquired skills in conveying light rays along a flexible arc were central to the achievement of the gastroscope. However, it was Schindler's basic ideas that eventually prevailed. Wolf had at first "proposed and constructed an optical gastroscope that was flexible throughout its length, but Schindler had the better idea of combining a rigid proximal half with a flexible distal half, thus producing a more widely instrument that conveyed a brighter, clearer image. The result was the famous Wolf-Schindler semiflexible gastroscope" (Haubrich, 1987, p. 6).4 Schindler, who was half Jewish, managed to escape Nazi Germany in 1934 and continued his practice and teaching of endoscopy in Chicago and, eventually, Los Angeles. His textbook, Gastroscopy, published in 1937 and in revised editions in 1950 and 1966, was "the gospel of gastroscopy for a generation of clinicians" (Haubrich, p. 6). While in Chicago, Schindler continued to be absorbed in ways of improving both the design and the construction of the gastroscope. As he had done with Wolf in Berlin, he formed a close connection with William J. Cameron. Cameron's firm, the Cameron Surgical Company, "became the world's largest supplier of illuminated instruments" (Haubrich, p. 7). Schindler 4   Patients may have opted for some modifier other than "semiflexible."

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Sources of Medical Technology: Universities and Industry worked especially closely with Louis Streifeneder, a talented instrument maker from Cameron's firm, who later formed his own company (the Eder Instrument Company) for producing high-quality laparoscopes. During World War II, with German instruments no longer available, Cameron's company introduced the Cameron Omniangle Gastroscope, a modification of the Wolf-Schindler gastroscope, which became a widely used standard instrument in the United States. It seems clear that, both in Germany and the United States, Schindler was responsible for numerous initiatives in the improved design of the gastroscope, in addition to his pioneering role in introducing it as a tool for extracting information from the patient's gastrointestinal (GI) tract. But the difficulties and limitations in gastroscopy before the advent of fiber optics are hard to exaggerate. It remained an unusual diagnostic procedure. At best, it afforded the examiner fleeting and partial visual impressions of only portions of the stomach as the gastroscopist attempted to manipulate a semiflexible instrument, with an incandescent light bulb at its distal tip, inside the gut of a (presumably) very uncomfortable and apprehensive patient. The innovation that was responsible for the transformation in endoscopy that began in the 1950s was the emergence of fiber optics. In principle, fiber optics allowed the design of flexible endoscopes, which offered the technical possibility of providing visual inspection of internal organs that were not readily accessible with rigid instruments or that were accessible to only a limited degree with the use of Schindler-type semiflexible endoscopes, for example, the duodenal bulb. The earliest applications of this new capability were on the GI tract, where flexibility was essential. But, as we will see, flexible endoscopy later had applications elsewhere where flexibility was also a critical feature. The Fiber-Optic Era Scientific research on the properties of light that are relevant to fiber-optic endoscopy has a long history. Fiber optics make it possible to transmit both light and images along a curved path through the use of bundles of long thin fibers of optical glass. The basic science underlying light transmission had been first expounded by the great Dutch scientist Christiaan Huygens in the seventeenth century. His formulation of the wave theory of light provided an explanation of refraction (bending) and reflection (Salmon, 1974). In 1870, at the Royal Society, John Tyndall demonstrated experimentally how light could be conducted along a curved path, the curved path in this case being a stream of water. Further experimentation was conducted in the 1920s and 1930s, and a patent on a technique for transmitting light through flexible quartz or glass fiber bundles had been taken out by Logie Baird in England in 1928. But these experiments led to no immediate useful applications. Fiber-optic endoscopy had its origins in the early 1950s, when research was begun on the possibility of transmitting images along an aligned bundle of flexible

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Sources of Medical Technology: Universities and Industry glass fibers. The findings of A. C. S. van Heel in Holland and H. H. Hopkins and his student, N. S. Kapany, in the department of physics at the Imperial College in London were simultaneously reported in Nature (Hopkins and Kapany, 1954; van Heel, 1954). These papers laid down the principles of coherent image transmission by means of fiber optics. Van Heel presented the concept of the coated glass fiber, although he discussed only the possibility of plastic coatings, which later turned out to be unsatisfactory. Both papers described a way of conveying optical images along a glass fiber—a concept that had an earlier history—but Hopkins and Kapany also elucidated the basic principles of fiber alignment. In these 1954 papers the authors made the linkage between their research and medicine; Hopkins and Kapany, for instance, observed that "[a]n obvious use of the unit is to replace the train of lenses employed in conventional endoscopes" (Hopkins and Kapany, 1954). It is important to observe that the work of van Heel and of Hopkins and Kapany was possible at this time because of major recent improvements in the manufacture of glass that had the effect of reducing the loss of light in transmission. If there is a single critical event in the early development of fiber-optic endoscopy, it was the reading of the Nature articles of Hopkins and Kapany and of van Heel by Basil Hirschowitz. Hirschowitz, a young South African gastroenterologist, went to the University of Michigan in 1953 on an American Cancer Society fellowship. Hirschowitz received some training in endoscopy as a medical student at the University of Witwatersrand and later at the Central Middlesex Hospital in London. He was very much aware of the limitations of the Schindler semiflexible gastroscope for upper GI endoscopy: "Half of the instrument could be flexed for introduction into the oesophagus, but once in the stomach, it had to be straight to accommodate the 50 or more lenses spaced along the shaft. Gastroscopy with the Schindler instrument required good training, a good assistant, and a patient with a compliant anatomy approaching that of a sword swallower" (Hirschowitz, 1989, pp. 247-250). According to Hirschowitz, from the time of his arrival at the University of Michigan Hospital in 1953 "we had become disenchanted with conventional upper GI rigid and semi-rigid endoscopy and more often than not the prevailing attitude in gastroenterology was to avoid rather than encourage its use" (Hirschowitz, 1989, p. 247). Discussions with C. Wilbur Peters, an optical physicist at the University of Michigan, convinced him of the feasibility of developing a fiber-optic instrument for visualizing the upper GI tract. In the summer of 1954, Hirschowitz visited Hopkins and Kapany in London where he examined their glass fiber bundle. The glass was inappropriate. It was commercially available glass of a kind used for glass cloth. It did indeed transmit an image, but was far from the stage of a practical instrument: "Light transmission was inadequate to produce the requisite one meter length for an endoscopy, the color of the light transmitted was green, and the image was not sharp" (Hirschowitz,

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Sources of Medical Technology: Universities and Industry 1989, p. 248). Nevertheless, Hirschowitz was persuaded that a workable instrument was attainable. Back at the University of Michigan, a young sophomore student by the name of Larry Curtiss was made a part of the team. It is worth observing at this point that Hirschowitz thought of the University of Michigan as a place where interdisciplinary communication and research was relatively easy. He recalled, "Ann Arbor was an exciting place to work, with bright, eager young men in various medical and non-medical disciplines. Interdisciplinary attitudes were strong at Michigan. For example, a group of about 10 of us used to meet one evening a week to discuss our research and to brainstorm over a can or two of beer" (Hirschowitz, 1979, pp. 864-869). Peters, Curtiss, and Hirschowitz confronted numerous difficulties. The fiber glass available at that time was inadequate and there was no commercially available apparatus for forming the fiber bundles. Fortunately, through Hirschowitz's connection with someone at the Corning Corporation in Midland, Michigan, they were given access to a supply of optical glass rods. Peters, Curtiss, and Hirschowitz then put together, from miscellaneous materials in the physics department basement, an apparatus for making fiber. A number of problems remained to be solved, including the proper orientation and protection of the fibers and the polishing of the ends to attain flat optical entry and exit surfaces. More serious difficulties centered on "cross talk" (i.e., when fibers come into contact light jumps from one fiber to another, leading to loss in image transmission). A crucial problem, then, was to develop a technique for insulating the fibers to eliminate cross talk. Eventually, by December 1956, Curtiss, the undergraduate, found a solution to the insulation problem. It was glass-coated glass fiber. Essentially, what he did was "to melt a rod of optical glass inside a tube of lower refractive index glass and pull the two together into a composite fiber" (Hirschowitz, 1979, p. 866). This provided a solution to the problems of insulation and excessive light loss. According to Hirschowitz, "That invention is the single most important optical advance in endoscopy. From then on it was purely a matter of applying and developing the process—we were home free" (Hirschowitz, 1979, p. 866). Hirschowitz tested the first operating gastroscope upon himself in February 1957: "I looked at this rather thick, forbidding but flexible rod, took the instrument and my courage in both hands, and swallowed it over the protests of my unanesthetized pharynx and my vomiting center" (Hirschowitz, 1979, p. 866). A few days later he used it to examine a patient suffering from a duodenal ulcer. Significantly, in view of the great impact it was to have in just a few years, the fiberscope generated little interest at first, even at the meeting of the American Gastroscopic Society in Colorado Springs in May 1957. (Schindler was in attendance. Kapany, who was also at the meeting, reported that the firm Bausch and Lomb, with whom he was working, would soon introduce its own fiberscope. They never did so.) Nor was there any initial enthusiasm among instrument

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Sources of Medical Technology: Universities and Industry manufacturers, either in the United States or England. Eventually American Cystoscope Makers, Inc. (ACMI), which had tried unsuccessfully to make usable fiber-optic bundles, undertook to manufacture fiberscopes, under license, but only if Curtiss, Peters, and Hirschowitz would agree to act as consultants. The agreement called for Curtiss and Peters "to get the glass fiber making off the ground with ACMI engineering staff" (Hirschowitz, 1979, p. 867). It should be particularly noted, then, that the academic/medical trio at the University of Michigan not only solved a critical technological problem with respect to the new device—the cladding of the glass fiber—but they were also instrumental in teaching the industrial firm how to solve some complicated manufacturing problems—the making of the fiber-optic bundles. This is a drastic departure from what might be regarded as the "normal" division of labor between academics and instrument manufacturers. The initial skepticism that greeted Hirschowitz's prototype fiberscope was hardly unusual. As suggested earlier, innovations commonly enter the world with poor performance characteristics and they often require years of attention and patient development work before they assert their technical superiority. This was graciously yet, at the same time, revealingly acknowledged, in the case of the fiberscope, by William Haubrich, himself an eminent authority on endoscopy: I recall having been shown this prototype instrument on a visit to Hirschowitz's laboratory. It was rigged so as to convey the visage of Abraham Lincoln that adorned a 5 cent stamp. Peering into the fiberscope, I could not deny recognizing Lincoln, but the quality of the image reminded me of a picture I had seen of prototype television images displayed in the 1920s. Vivid it was not. Comparing this with the image then obtained by the lens-and-prism gastroscope, I confess I saw little future in fiberoptic endoscopy. A remarkable accomplishment, I thought, but little will come of it. Now, along with thousands of other endoscopists the world over, I rejoice in my lack of prescience (Haubrich, 1987, p. 13). The instrument went through a succession of improvements in four or five months until the so-called Mark V, the ACMI 4990 Hirschowitz fiberscope ("the model T of fiber-optic endoscopy") was introduced. The results of its early use were reported in Lancet in May 1961, accompanied by color photographs. Such photographs were extremely important for purposes of documentation.5 5   In the Lancet article Hirschowitz stated: "The application of fiber optics to the examination of the upper gastrointestinal tract has opened new dimensions in diagnostic endoscopy. Areas not previously accessible are now readily displayed—the pyloric canal, the duodenal bulb, and both afferent and efferent loops of the jejunum through the gastroenterostomy stoma. These areas can not only be studied for abnormalities but also for motility for comparatively long periods. Furthermore, the complete flexibility of the fiberscope means that examination is very much easier for the patient, and introduction of the instrument requires no special skill. More important, damage to the oesophagus or stomach, particularly the oesophagus, is no longer a consideration as it was with the conventional gastroscope. Thus, many more patients can be examined easily and safely and the indications for its use should be much broader" (Hirschowitz, 1961, pp. 1074-1078).

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Sources of Medical Technology: Universities and Industry Firms other than ACMI attempted to develop and manufacture flexible endoscopes. The American entrants, such as the Eder Instrument Company, had no success (Louis Steifeneder, founder of the company, had, as we have seen, worked with Schindler at an earlier period). American Optical Company did introduce a flexible endoscope, but a long patent infringement suit, eventually won by ACMI, developed between ACMI and American Optical (AO). Whereas ACMI had filed patents in the United States and Europe, it had not filed a patent in Japan, which is surprising in view of the fact that GI problems had long constituted a major health problem in that country. During the 1960s, AO licensed the technology to the Olympus Corporation of Japan and to Machida Instrument Company, which were already producing semirigid endoscopes. The Japanese firms, in particular Olympus, had also developed a gastrocamera even before the introduction of the fiberscope. The ability to obtain good color photographs of the GI tract was extremely important for documentations, as well as for consultation, and for teaching purposes. Photographs and even moving pictures had long been considered and attempted, with no particular success. For many years the best visual representation of gastric anomalies had been the work of artists. The gastrocamera was developed by T. Uji, working with Olympus. Olympus introduced the gastrocamera as early as 1955, and it came into widespread use in Japan by the early 1960s. According to Haubrich (1987, p. 11), there were 10,000 gastrocameras in Japan in 1966. The gastrocamera reflected the remarkable Japanese skills in camera miniaturization, and it took pictures of extremely high quality. The gastrocamera, however, had severe limitations. The camera was attached to the tip of the endoscope. It took pictures from a number of preset positions, and the operator could inspect the contents of the patient's stomach only after the film had been developed. Moreover, swallowing a camera, even a miniaturized one, remained a distinctly unwieldy and unpleasant experience. The gastrocamera was never widely adopted in the United States, in spite of the efforts of John Morrissey of the University of Wisconsin (Perna et al., 1965). It was overtaken by the improvements in fiber-optic technology: ''[A]s the optical system of the fiberscope was rapidly improved, it soon thereafter became much easier for most endoscopists to simply attach an external 35 mm camera to the eyepiece of the gastroscope and photograph the image conveyed by the fiber bundle. … The gastrocamera, marvelous as it was, became obsolete" (Perna at al., 1965). Further Refinements and New Clinical Applications In the late 1960s fiber-optic endoscopes were refined in many ways: "Among notable improvements were those of optical clarity, in wieldiness and manipulability of the distal tip, and in provision of channels for biopsy and therapeutic maneuvers. The Japanese were especially intent on this work because of

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Sources of Medical Technology: Universities and Industry the need to precisely diagnose gastric cancer" (Haubrich, 1987, pp. 11-13). Within a short period of time fiber-optic techniques were being used "to inspect any and all cavities and potential cavities in the body" (Hirschowitz, 1979, p. 868). It is particularly appropriate, in accordance with our emphasis on the interdisciplinary aspect of this technology, that one of the early applications of this newly developed capability was a special gastroscope developed in 1962 that would allow Rolls Royce to inspect the interior of aircraft engines without having to undertake expensive and time-consuming dismantling. After its initial successes in the upper GI tract, fiber-optic technology quickly spread to other gastroenterological uses. Employing a fiber-optic bundle with a working length of 75 centimeters (cm), the esophagoscope—an end-viewing modification of Hirschowitz's side-viewing fiberscope—became the first fiber-optic endoscope to achieve widespread use. After the working length of the fiberscope was extended to 110 cm "we had an easily insertible instrument with which the esophagus, stomach, and duodenum could be scrutinized all in the same procedure" (Haubrich, 1987, p. 13). Fiber-optic endoscopy has been of particular value in colonoscopy, where flexibility is essential. The extremely sharp curvature of the sigmoid colon rendered it inaccessible to examination with a rigid, lens-and-prism endoscope. Before fiber optics, proctosigmoidoscopes, could inspect only 25-30 cm of the proctosigmoid. Fiberoptic colonoscopy originated in the 1960s at the academic medical center of the University of Michigan, where Hirschowitz had done his earlier work. It was pioneered by Bergein Overholt. Overholt reported the results of his first examinations at the 1967 meeting of the American Society for Gastrointestinal Endoscopy. An important feature of the application of endoscopy to the examination of the colon is that it led very quickly to a new therapeutic procedure of great value: polypectomy. Since polyps, especially multiple polyps, sometimes turn malignant, the opportunity to diagnose and to maintain regular surveillance is extremely valuable. Overholt reports that the U.S. Public Health Service awarded a grant to Optics Technology, Inc., of California for the development of a flexible sigmoidoscope (the president of this company was N. S. Kapany, who had moved from London to the United States, eventually to California). This early attempt at design and development was unsuccessful: "[I]t became apparent that more information on the anatomy of the colon was needed for engineers to develop instrument prototypes" (Overholt, 1981, p. 2). Important assistance in securing this information was provided by Dow-Corning Aid to Medical Research. As Overholt observes: "Although many companies became interested in this new field, it was the Illinois Institute of Technology Research Institute and the Eder Instrument Company that developed the first successful prototypes of the flexible fiberoptic sigmoidoscope. After somewhat difficult trials in animals, clinical experimentation began" (Overholt, 1981, p. 3). Parallel development work was being conducted in Japan during the 1960s,

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Sources of Medical Technology: Universities and Industry with early colon fiberscope prototypes being designed by clinicians in cooperation with Machida and Olympus. Nevertheless, "the first true colonoscope" was developed by ACMI in the late 1960s. The technique of colonoscopic polypectomy was first introduced by Hiromi Shinya, working at the Beth Israel and Mt. Sinai Medical Centers in New York, in 1969. By 1982, Dr. Shinya could report that he had "performed approximately 45,000 colonoscopies and more than 10,000 polypectomies for various lesions larger than 0.5 cm in diameter" (Shinya, 1982, p. v.). Dr. Shinya "made the outstanding contribution of polypectomy using an expandable wire-loop snare inserted through a channel of the colonoscope. Shinya was able to remove polyps safely, thus avoiding the necessity of repeated barium enema observation and transabdominal colotomy for polypectomy" (Overholt, 1981, p. 5). In this way, the technology of diagnosis had also become a direct part of the technology of therapy. Another application in which endoscopy moved from being a diagnostic to a therapeutic technology is in bile duct stones. During the early 1950s, the Richard Wolf Company had introduced a choledochoscope that could be used during surgery for visualizing the interior of the common duct. In subsequent years, the German optics company Karl Storz introduced an improved rigid choledochoscope and ACMI a flexible fiber-optic choledochoscope (Wildegans, 1960). Yet despite these advances, surgeons were reluctant to adopt routine use of this procedure. Initial sources of this reluctance included concern about possible increases in operating time, rates of wound infection, and other morbidity. Failure to appreciate the high incidence of retained stones and difficulties in changing a routine may also have played a role. A major step forward in diagnosis came with the introduction of endoscopic retrograde cholangiopancreatography (ERCP) in 1970 in Japan (Oi et al., 1970). This technique involved moving an endoscope through the duodenum and then in retrograde manner into the biliary tract to view the common duct. Development and manufacturing of these endoscopes were undertaken by Olympus and Machida. Gastroenterologists in Japan and also in Germany began experimental animal work to test the endoscope as a therapeutic tool in the common bile duct. Because in the early 1970s surgical intervention in the case of recurrent or retained common duct stones carried a significantly high mortality risk, there was a clear need for a safer procedure. Risks were especially high for elderly and frail patients with comorbidities. Thus, in 1974, gastroenterologists from university clinics in Germany and Japan for the first time extended the use of ERCP from diagnosis to therapy in this patient group. This technique, a so-called endoscopic sphincterotomy, soon demonstrated considerable advantages over operation procedures for duct stones and, as practitioners acquired the necessary skills, clinical results improved (Classen and Demling, 1974; Kawai et al., 1974). During the late 1970s, video-guided endoscopy had become reality with the introduction of add-on television cameras to the endoscope and videorecorders for the permanent storage of images. A revolutionary change, however, was

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Sources of Medical Technology: Universities and Industry and most importantly, in the mid-1980s, gastroenterologists and interventional radiologists introduced gallstone lithotripsy (originally developed for kidney stones). Although we now know that lithotripsy involves lengthy treatment periods, is applicable only to a minority of patients, has high costs, and carries a high risk of recurrence after successful treatment, at the time lithotripsy seemed to have a potential similar to that of tagamet and other H2-blockers, which essentially led to the disappearance of ulcer surgery. These competitive pressures would be an important factor in inducing surgeons to develop laparoscopic cholecystectomy. In March 1987, Philippe Mouret in Lyons, France, performed the first human laparoscopic cholecystectomy using a gynecological instrument. Concurrently, two centers in France and two in the United States began to further develop the technique (Dubois et al., 1989; Perissat, 1992; Reddick et al., 1989). As the laparoscope was similar to that used in gynecology, leading manufacturers of rigid endoscopes, such as Storz and Wolf, early on saw a major new opportunity and quickly capitalized on their technologies and reputations. In particular, their ability to provide add-on video cameras that could provide high-resolution realistic color images on a videomonitor was of utmost importance. Laparoscopic cholecystectomy generally involves three to four punctures and a team of three professionals inserting the necessary instruments into the abdomen, which underscores the importance of other members of the surgical team being able to observe the operation so that they can provide useful assistance. These clinicians also realized that applying surgical sutures through an endoscope was difficult and particularly time-consuming and would discourage a major part of the surgical profession from adopting the technique. The surgeons Reddick and Olsen worked together with U.S. Surgical, an existing wound closure company that more than 20 years ago developed a stapling device, to adapt this device for use through an endoscope. This achievement facilitated the application of laparoscopic cholecystectomy tremendously, and in the early 1990s U.S. Surgical because the dominant firm in this field. U.S. Surgical's leading position, however, is currently being contested by Johnson & Johnson's newly formed Ethicon Endo-Surgery division (Ethicon was the leading sutures manufacturer, making more than 80 percent of all sutures in the United States). Finally, in European centers, the gallbladder itself was dissected from the liver by electrocautery devices, which had been available in all operating rooms since the 1960s. In the United States, laser companies were able to establish a link between their technologies and laparoscopic cholecystectomy. The application of lasers to laparoscopic cholecystectomy required major changes in the delivery of laser energy. Because CO2 energy cannot be transmitted through endoscope fiber optics, CO2 lasers were not useful. Laser companies, such as Coherent, Trimedyne, and Laserscope, developed argon, dual wavelength KTP, and contact yttrium-aluminum-garnet (YAG) lasers for use in laparoscopic

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Sources of Medical Technology: Universities and Industry cholecystectomies for which they sought FDA approval in 1989 and 1990 (Biomedical Business International, 1992). These clinician-innovators and the industrial firms involved presented videotapes of the first laparoscopic cholecystectomy at surgical society meetings in 1989 (not during scientific sessions, but in the technical exhibition hall), and afterward the procedure underwent rapid diffusion, particularly in the United States. Table 4-1 shows the volume of laparoscopic and endoscopic procedures by specialty in 1991. A variety of factors played a role in the widespread adoption of the procedures by surgeons, including the above-mentioned provider competition. In addition, laparoscopic equipment received rapid regulatory approval because it was deemed "substantially equivalent" to the laparoscopes and soft-tissue lasers that were on the market before the 1976 Medical Device Amendments to the Food and Drug Act took effect. (Approval of the equipment was handled through a so-called 510[k] procedure rather than the full premarketing approval (PMA) review.) Moreover, payers supported use of the new technique because it promised significant cost savings. In addition, laparoscopic cholecystectomy was financially attractive to U.S. hospitals as they were reimbursed initially by Medicare at rates equal to conventional cholecystectomy. Relatively low start-up costs also contributed to diffusion: neither major changes in health care facilities nor large capital expenditures were required (unless a facility had to purchase a laser, which costs between $100,000 and $200,000). Last, but certainly not least, patient demand for the procedure was particularly high because it promised to be less painful, caused minimal scarring, and allowed earlier return to active life. To accommodate the burgeoning demand, industry built commercial training TABLE 4-1 Top 12 Laparoscopic or Endoscopic Procedures by Volume, 1991 Procedure Specialist 1991 Esophagogastroduodenoscopy Gastroenterologist 582,000 Colonoscopy Gastroenterologist 272,000 Proctosigmoidoscopy Gastroenterologist 240,000 Gastroenterologic biopsy Gastroenterologist 240,000 Tubal ligation Gynecologist 177,000 Cholecystectomy General surgeon 127,000 Uterine adhesiolysis Gynecologist 120,000 Gastroenterologic polypectomy Gastroenterologist 64,000 Transurethral prostatectomy Urologist 53,000 Gynecologic polypectomy Gynecologist 64,000 Herniorrhaphy General surgeon/urologist 45,000 Appendectomy   General surgeon 42,000   SOURCE: Biomedical Business International, 1991.

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Sources of Medical Technology: Universities and Industry centers that provided hands-on experience in animals and simultaneously introduced surgeons to procedure-related products. With the introduction of commercial interests, the training process of surgeons in new procedures, which traditionally had been undertaken by other surgeons, underwent fundamental change. In the United States, more than 50 percent of the nation's 32,750 practicing general surgeons learned laparoscopic cholecystectomy during the 18 months after the procedure was introduced (White, 1991). Moreover, following the introduction of laparoscopic cholecystectomy, the pool of patients undergoing gallbladder removal expanded from sicker to mildly symptomatic patients (suggesting that this procedure is becoming at least partly prophylactic) as well as to higher-risk patients once considered ineligible for the procedure. As a result, the overall level of gallbladder removals increased (Legoretta et al., 1993). This means that, although laparoscopic cholecystectomies reduce unit costs by 25 percent (mostly because of shorter hospital stays), their introduction has resulted in an increase, not a decrease, in aggregate expenditures (Legoretta et al., 1993). Adoption rates in Europe show a different trend: slower diffusion at half the rate seen in the United States. Several factors may account for the difference. One reason for this slower diffusion may be differences in payment mechanisms, especially in view of European reliance on hospital budgeting systems. In addition, European endoscope manufacturers, like Storz and Wolf, initially focused on the U.S. market and were unable to meet European demands for equipment. European restrictions on the use of animals for training purposes are another factor. These regulations require the use of operative simulators and observational methods, which can slow the time necessary to bring a surgeon to an adequate level of clinical competence (Biomedical Business International, 1992). Rapidly escalating professional and patient demand for a less invasive way to remove gallstones precluded the performance of a controlled trial to establish the safety, efficacy, and indications for laparoscopic cholecystectomy. As a result, assessment relied on a large number of prospective case studies that reported equivalent patient outcomes in comparison to the open procedure. A greater number of serious procedure-related complications (e.g., bile duct injuries) were reported for laparoscopic cholecystectomy, but these seemed to be offset by the reported decreases in pain, co-morbidity-related complications (e.g., stroke, pulmonary embolism), hospital length of stay, and recovery period that resulted from the laparoscopic approach (Perissat and Vitale, 1991). For example, hospital length of stay decreased from four to six days to an overnight or ambulatory procedure; and return to work or normal activity decreased even more dramatically, from four to six weeks to less than one week (Southern Surgeons Club, 1991). As with other surgical procedures, complication rates fell with operative experience. A "learning curve" for laparoscopic cholecystectomy has been well described, with rates of adverse events for an individual surgeon decreasing with operative experience. Laparoscopic cholecystectomy requires skill, dexterity,

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Sources of Medical Technology: Universities and Industry and the ability to perform surgery with a two-dimensional view of the patient's organs. It also requires coordination of hand motions that may appear reversed on the video monitor if the camera is directed at the surgeon. As a result of the often inadequate training of surgeons in this new technique, reports of surgical complications began to increase and cast a shadow over this new procedure. This led the state of New York to issue guidelines that require surgeons to perform at least 15 procedures under supervision before they can operate independently. With the rapid dissemination of laparoscopic cholecystectomy came a large demand for the tools of the trade. All existing endoscope companies began to cater to the general surgeon and this sparked an unprecedented level of industrial competition both among existing endoscope manufacturers and new companies. In 1990, more than 80 companies had started to develop laparoscopy products. Along which lines did these companies compete? First, they put emphasis on developing a continuous stream of new and modified products (many of which are obsolete in as little as four to six months) and low-cost manufacturing methods. Second, the composition of R&D teams underwent considerable change. Ethicon Endo-Surgery, for example, quadrupled its engineering staff from 1989 levels. In their quest to develop new instruments, companies began to work more closely and earlier in the development process with surgeons they consider thought-leaders or innovators. Several firms also have added surgeons to their in-house R&D teams, and have started to provide their engineers with clinical training. Moreover, as the possibility of integrating minimally invasive devices with biologicals emerges on the technological horizon, some firms are extending their R&D teams in the direction of molecular biologists. Finally, a dynamic pattern of interindustry alliances, acquisitions, and mergers is emerging. For example, Olympus and Ethicon Endo-Surgery signed a cooperative agreement to share R&D marketing, and particularly training programs, whereas the camera firm Cabot Medical merged with the electrocautery manufacturer Birtcher to become a full-line supplier of products. Moving from the rate to the direction of development, manufacturers are still now focusing on improving the ease of device operation by developing improved organ extractors and trocars, robotic arms, and modified suture applicators. Moreover, camera manufacturers are focusing on improving visualization and clarity by incorporating new chip technology into their cameras, as well as monitoring advances in high-definition television for its application in medical video imaging. Furthermore, the ongoing conversion of other traditionally open surgical procedures, such as hernia repair, vagotomy, appendectomies, colon surgery, and bowel resection, to laparoscopic procedures is leading to the demand for new instrumentation. Bowel resection, for example, requires larger instruments to be passed through the laparoscope which, in turn, requires large operating channels. The conversion of these procedures is, however, occurring much less rapidly than was the case with laparoscopic cholecystectomy. This slower diffusion process is a result of the recognized need for special training, the longer operating

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Sources of Medical Technology: Universities and Industry room time involved in these laparoscopic procedures, and the more recent reluctance of payers to cover these procedures because of the possibility of expansions of use (Halter, 1994). Finally, increasing competition among suppliers has meant that price and operating costs are beginning to play a role in decisions about development targets. For example, in the early stages of use of laparoscopic cholecystectomy, lasers were preferred over electrocautery as the gallbladder dissection method of choice in the United States. Large case series comparing the two techniques demonstrated that both were safe and effective, but electrocautery was shown to be less expensive and is now used in the majority of cases (Southern Surgeons Club, 1991). Another issue has been whether to focus on the development of reusable or disposable products. In Europe, the emphasis has been on improving reusable devices, as a result of concerns over equipment cost and toxic waste disposal, which tend to be stronger there than in the United States. Wolf, for instance, has developed a reusable trocar that can be easily resharpened. The U.S. firms, particularly U.S. Surgical and Ethicon, focused on disposable instruments, arguing that disposables protected against cross-infections and did not require the time and costs of sterilization and repackaging. Reusable instruments manufacturers countered these charges by arguing that reusables were more cost-effective, and the disposable manufacturers now increasingly started to compete on the basis of price. U.S. Surgical, for example, announced at the 1992 American College of Surgeons meeting that it would bring a disposable laparoscope to the market for less than $200. SOME CONCLUDING OBSERVATIONS AND SPECULATIONS First, some brief observations about the nature of the interdisciplinary relationship in endoscopy. This chapter indicates that endoscopic innovation has indeed been highly dependent on scientific and engineering advances that are generated outside of the medical sector, such as fiber optics, color television, and charge couple devices. This characteristic has important implications for the timing of innovation: it means, for example, that the realization of the first endoscope—which had been conceptualized already in the Middle Ages—and subsequent modifications of existing equipment had to await advances in areas of science and technology over which the medical profession had little to no control. Yet we are oversimplifying a complex and subtle relationship if we picture medicine merely as a passive receiver. In the case of fiber optics, for instance, attempts by Hirschowitz, Curtiss, and Peters to develop a flexible GI endoscope led them to solve two major problems that properly belonged to the realm of physics and engineering: (a) by coating the fibers with glass of a lower refractive index they successfully addressed the critical problem of "cross talk," and (b) they created a novel process for manufacturing aligned flexible fiber bundles. Thus, certain key manufacturing problems, which had to be resolved before fiber

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Sources of Medical Technology: Universities and Industry optics could obtain its widespread industrial usage, were first addressed in the academic/medical community, not the industrial community. These advances, in turn, made an important contribution to optical physics research and the eventual application of fiber optics and endoscopes in other sectors of the economy, such as telecommunications, but also the defense and aircraft industries. In sum, fiber optics, a major medical innovation, not only came into the world through medical instrumentation, but the medical world itself made significant contributions to the advancement of that technology. As Kapany observes: "From a historical viewpoint, the very origin of fiber optics is intimately linked with its application in medicine." Given the inherently interdisciplinary nature of endoscopic innovation, it is not surprising that close interactions between user clinicians and industrial firms, often in academic medical centers, were found to be crucial to the successful development of medical technology. These interactions are important for a variety of reasons that move beyond the stylized view of the division of labor between academic and industrial settings. This oversimplified view may be summarized in the following manner: Clinicians in universities undertake biomedical research and provide feedback about the shortcomings of technologies when introduced into clinical practice; this knowledge then leads industry to develop and manufacture new and improved technologies. Whereas the behavior of clinicians who adopt or reject certain technologies over time has indeed fed back important signals to industrial firms about the kinds of projects that may be worthwhile to undertake, our study material suggests that the medical profession also plays a more active role in the development of new products. The majority of endoscopic innovations considered in this analysis are user dominated, in the sense that clinicians were instrumental in designing and developing the prototype and not merely in articulating the need for some specific new instrument. However, and perhaps more unexpectedly, the medical/academic world in certain cases (e.g., the development of the first flexible fiberscope) also solved what in essence were a set of manufacturing problems and provided expertise about the scaling up for production to the industrial firm—activities normally thought of as the proper domain of the manufacturing sector. Our study points to an additional, and quite significant, finding, and that is that the existing disciplinary boundaries internal to medicine itself may have constituted an even more serious obstacle to innovation than those external to medicine. Put somewhat differently, the most difficult barriers that needed to be crossed were not between medicine and industry, but barriers within medicine itself. For example, the transfer of laparoscopy from gynecology to surgery seems to have taken an unnecessarily long time. Whereas this lag may be partially explained by the fact that more complex surgical procedures had to await the introduction of complementary technologies (such as video endoscopy), this alone does not appear to provide a satisfactory explanation. The delay in transfer appears to be intimately linked to issues surrounding the definition and the

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Sources of Medical Technology: Universities and Industry boundaries of clinical specialties. As mentioned, internal medicine and its subspecialties, such as gastroenterology, have traditionally borne primary responsibility for diagnostic activities, and endoscopic tools were part and parcel of the culture and training of these specialties. The adoption of flexible endoscopic procedures by gastroenterologists and other internists was generally rapid, particularly in those cases—such as colonoscopy—where the new procedure did not displace an older procedure with vested interests. By contrast, recent generations of surgeons had little training in endoscopic procedures, and, as described above, laparoscopy was in many ways contrary to the culture of surgery. Indeed, for many decades surgeons were not particularly interested in the adoption of surgical laparoscopy. Starting in 1989, however, the attitudes of surgeons underwent major change, and—as mentioned—in the United States more than half of all general surgeons acquired the necessary skills within 18 months, a breathtakingly rapid adoption of a new medical procedure by any historical standard. It is interesting to note that this adoption process was, at least in part, a generational phenomenon. Preliminary evidence of a major study by the American College of Surgeons indicates that younger surgeons, who lacked the lifelong investment in the older procedure, were more willing to invest the time and take the risks involved in adopting laparoscopic cholecystectomy. How can we reconcile the apparently conservative attitude of surgeons throughout most of the previous decades with this sudden switch in the 1990s? Although strong demand by patients and payers for less invasive and less costly procedures certainly was an important factor, and a factor that became more important over time, our study suggests the possibility that interspecialty competition may well have played the dominant role. In particular, the development and introduction of gallstone lithotripsy by gastroenterologists and interventional radiologists during the mid-1980s appeared to pose an important threat to the position of surgeons in the treatment of gallstone disease. These competitive pressures, compounded by a growing concern over health care costs (see below), induced surgeons to adopt and further develop laparoscopic cholecystectomy, which subsequently has effectively challenged the then-perceived advantages of biliary lithotripsy. The adoption of laparoscopy by the surgical profession led to a high level of industrial innovation and competition, as indicated by the entry of new firms into the market and the continuous stream of new products. This competitive environment also stimulated a stronger focus on interdisciplinary R&D than in earlier times. For example, in previous decades industrial firms, such as Storz, had consultancy arrangements with leading clinicians, such as the gynecologist Semm. Nowadays, these consultancy arrangements are still important, but a new arrangement for piercing disciplinary boundaries is becoming apparent: the composition of the R&D team is undergoing significant change in that surgeons are becoming part of the in-house R&D team and engineers are receiving more extensive clinical training. The academic-industry interface is also changing in

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Sources of Medical Technology: Universities and Industry other ways: for the first time in the history of surgery industry has become actively involved in teaching these new procedures. At this point, it seems important to emphasize the industrial experience with these technologies: new technologies once introduced into the world often take on a subsequent life of their own. Commercial success or failure turns upon considerations of a very different sort than those we have considered so far. For example, many of the original rigid GI endoscope manufacturers failed to make the discontinuous leap to a world of fiber optics and were driven out of the industry. ACMI, a leader in the early development of flexible fiber-optic endoscopes, subsequently lost its market position to Japanese producers (just like the Eder Instrument Company with the sigmoidoscope). Indeed, Olympus now controls 75 percent of the world market in gastroenterological endoscopy. It appears that the conditions determining eventual commercial success with new technologies may be very different from those determining success in making the initial innovation. As a conjecture, Olympus's success would appear to result from its unique strengths in both sales and after-sales service and maintenance, as well as from its flexibility and speed in responding to user needs. The issues of interspecialty and interindustry competition are, in turn, closely linked to changes that are presently occurring in the delivery and financing of health care. In the 1980s, attempts to control the rising costs took on a new urgency, and are leading to major changes in the payment system and the incentives incorporated in this system. This has affected the rate, but also the direction, of technological change. The direction in which industrial developers try to move their technologies is embodied in their selection of R&D projects. In the period before these constraints came into play, judgments by the relevant medical specialty about a technology's clinical performance have predominated in determining the directions in which improvements are sought, and feedback signals are often couched in terms of shortcomings in the efficacy and safety of existing treatment options. Problems involving the ease of operation of the technology for professionals or the quality of care for patients have been another important influence. Yet, in the case of surgical laparoscopy the first signs (e.g., the debate on reusables versus disposables, or the emerging preferences for electrocautery over lasers) are appearing that economic considerations will increasingly influence the direction of technological change in the years to come. These preliminary conclusions suggest an agenda for future research. First on this agenda is the matter of interspecialty competition. Whereas the economics literature has extensively debated the ways in which competition among industrial developers may affect the pace of generating and developing new technologies, there is no discussion in the literature of the phenomenon of competition among user groups . A careful examination of the effects of interspecialty competition on the rate and direction of technological change may be a fruitful area of further research. The second issue, in these times of health care reform, concerns how new incentives might be introduced to deal with the tension between

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Sources of Medical Technology: Universities and Industry cost containment on the one hand and medical innovation on the other. How can we devise financial incentives to induce the medical-industrial world to develop cost-reducing new technologies? This is not—yet—a well-formulated question because the impact of a new medical technology on health care costs is not something that is intrinsic in a piece of hardware, such as an endoscope. It will depend also upon the sort of use that the medical profession choses to make of that hardware, and those choices will also be shaped by the prevailing payment system. These are issues that have yet to be examined. REFERENCES Anderson, E. T. 1937. Peritoneoscopy. American Journal of Surgery 35:36–39. Berci, G., Adler, D. A., Brooks, P. G., Pasternak, A., and Hasler, G. 1973. The importance of instrumentation and documentation in gynecological laparoscopy. Journal of Reproductive Medicine 10:276–284. Berci, G., and Davids, J. 1962. Endoscopy and television. British Medical Journal 1:1610–1613. Berci, G., Adler, D., Brooks, P. G., Pasternak, A., and Hasler, G. 1973. The importance of instrumentation and documentation in gynecological laparoscopy. Journal of Reproductive Medicine 10:276–284. Biomedical Business International. 1992. U.S. market for products in laparoscopic/endoscopic surgery. Santa Ana, Calif. Classen, M., and Demling, L. 1974. Endoskopische Sphincterotomie der Papilla Vateri und Steinextraktion aus dem Ductus Choledocus. Deutsche Medische Wochenschrifte 99:496–497. Classen, M., and Phillip, J. 1984. Electronic endoscopy of the gastrointestinal tract: Initial experience with a new type of endoscope that has a new fiberoptic bundle for imaging. Endoscopy 16:16–19. Dubois, F., Berthelot, G., and Levard, H. 1989. Cholécystectomy par coelioscopy. Nouvelle Presse Medicale 18:980–982. Filipi, C. J., Fitzgibbons, R. J., and Salerno, G. M. 1991. Historical review: Diagnostic laparoscopy to laparoscopic cholecystectomy and beyond. In: K. A. Zucker, ed. Surgical Laparoscopy. St. Louis: Quality Medical Publishing, pp. 3–21. Fourestier, M., Gladu, A., and Vulmière, J. 1952. Perfectionnements à l'endoscopie médicale. Réalisation bronchoscopique. La Presse Médicale 60:1292–1294. Gaskin, T. A., Isobe, J. H., Mathews, J. L., Winchester, S. B., and Smith, R. J. 1991. Laparoscopy and the general surgeon. Surgical Clinics of North America 71:1085–1097. Gunning, J. E. 1974. The history of laparoscopy. In: Gynecological Laparoscopy: Principles and Techniques. J. M. Phillips and L. Keith, eds. New York: Stratton Intercontinental Medical Books, pp. 57–66. Halter, P. 1994. Minimally invasive surgery. Medical Device & Diagnostic Industry (January):68–72. Haubrich, W. S. 1987. History of endoscopy. In: Gastroenterologic Endoscopy. M. V. Sivak, ed. Philadelphia: W. B. Saunders.

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Sources of Medical Technology: Universities and Industry Hirschowitz, B. I. 1961. Endoscopic examination of the stomach and duodenal cap with the fiberscope. Lancet 1:1074–1078. Hirschowitz, B. I. 1979. A personal history of the fiberscope. Gastroenterology 76:864–869. Hirschowitz, B. I. 1989. The fiber-optic era in endoscopy—beginnings and perspectives. Italian Journal of Gastroenterology 21:247–250. Hopkins, H. H., and Kapany, N. S. 1954. A flexible fiberscope, using static scanning. Nature 17:39–41. Hulka, J. F., Fishburne, J. I., Mercer, J. P., et al. 1973. Laparoscopic sterilization with a spring-loaded clip: A report on the first fifty cases. American Journal of Obstetrics and Gynecology 116:715. Isselbacher, K. J. 1972. A medical treatment for gallstones? New England Journal of Medicine 286:40–42. Kalk, H. 1929. Erfahrungen mit der Laparoskopie. Zeitschrift fur Klinische Medizin 14:303. Kawai, K., Akasaka, Y., Murakinu, K., et al. 1974. Endoscopic sphincterotomy of the ampulla of Vater. Gastrointestinal Endoscopy 20:148–151. Kodama, F. 1992. Technology fusion and the new R&D. Harvard Business Review, July-August, pp. 70–78. Langenbuch, C. 1882. Ein Fall von Exstirpation der Gallenblase wegen chronischer cholelithiasis: Heilung. Berliner Klinische Wochenschrift 19:725–727. Leape, L., and Ramenofsky, M. L. 1980. Laparoscopy for questionable appendicitis. Annals of Surgery 191:400–413. Legoretta, A.P., et al. 1993. Increased cholecystectomy rate after the introduction of laparoscopic cholecystectomy. Journal of the American Medical Association 270: 1429–1432. Liskin, L., Rinehart, W., Blackburn, R., and Rutledge, A. H. 1985. Female sterilization. Population Reports 9:128–129. Oi, I., Kobayashi, S., and Koudo, T. 1970. Endoscopic pancreatocholangiography. Endoscopy 2:103–106. Overholt, B. F. 1981. The history of colonoscopy. In: Colonoscopy Techniques. R. H. Hunt and J. D. Waye, eds. London: Chapman and Hall. Palmer, R. 1947. Instrumentation et technique de la coelioscopie gynécologique. Gynecologie et Obstetrie (Paris) 46:420–431. Palmer, R. 1962. Essais de sterilisation tuballe coelioscopique par electrocoagulation isthmique. Bulletin de la Féderation des Sociétiés de Gynecologie et d'Obstetrique de Langue Française 14:298–301. Perissat, J. 1992. Laparoscopic Cholecystectomy—The European Experience. Presentation at the Consensus Development conference, National Institutes of Health, Bethesda, Md., September14–16. Perissat, J., and Vitale, G. C. 1991. Laparoscopic cholecystectomy: Gateway to the future. American Journal of Surgery 161:408. Perna, G., Honda, T., and Morrissey, J. 1965. Gastrocamera photography. Archives of Internal Medicine 116:434–444. Reddick, E. J., Olsen, D., Daniell, J., Saye, W., et al. 1989. Laparoscopic laser cholecystectomy. Laser Medical and Surgical News Advances (February):38–40.

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Sources of Medical Technology: Universities and Industry Rioux, J. E. 1989. Female sterilization and its reversal. In: Contraception: Science and Practice. M. Filshie and J. Guilleband, eds. London: Butterworths, pp. 275–291. Rioux, J. E., and Cloutier, D. 1974. A new bipolar instrument for laparoscopic tubal sterilization. American Journal of Obstetrics and Gynecology 119:737–739. Salmon, P.R. 1974. Fiber-optic Endoscopy. New York: Pittman Medical Publishing Co. pp. 4–5. Semm, K. 1977. Atlas of Gynecologic Laparoscopy and Hysteroscopy. Philadelphia: W. B. Saunders. Semm, K. 1987. Operative Manual for Endoscopic Abdominal Surgery. Chicago: Year Book Medical Publishers. Shinya, H. 1982. Colonoscopy: Diagnosis and Treatment of Colonic Diseases. Tokyo: Igaku-Shoin, p. v. Soulas, A. 1956. Television bronchologie et pneumologie. La Presse Médicale 64:97–99. Southern Surgeons Club. 1991. A prospective analysis of 1,518 laparoscopic cholecystectomies. New England Journal of Medicine 324:1073–1078. Steptoe, P. C. 1967. Laparoscopy in Gynecology. Edinburgh: Livingstone. van Heel, A. C. S. 1954. A new method of transporting optical images without aberrations. Nature 17:39. Wheeless, C. R., Jr. 1972. Elimination of second incision in laparoscopic sterilization. Obstetrics and Gynecology 39:134–136. White, J. V. 1991. Laparoscopic cholecystectomy: The evolution of general surgery. Annals of Internal Medicine 115:651–653. Wildegans, H. 1960. Die Operative Gallengangsendoskopie. Munchen: Urban and Schwarzenberg. Wortman, J., and Piotrow, P. T. 1973. Colpotomy: The vaginal approach. Population Reports 3:29–44. Yoon, J. B., and King, T. M. 1975. A preliminary and intermediate report on a new laparoscopic tubal ring procedure. Journal of Reproductive Medicine 15:54–56.