Introduction

One of the most spectacular fields of medical device innovation since the end of the Second World War has been the field of diagnostics. Here we have seen the successive introduction of a wide range of sophisticated diagnostic devices, such as computed tomography (CT) scanners, magnetic resonance imaging (MRI) machines, and fiber-optic endoscopes. These devices have undoubtedly transformed modern medical practice, but have also resulted in significant changes in the industrial organization of the diagnostic medical devices sector. Unlike the rest of the medical device industry, which consists of a large number of small firms, the medical imaging sector is one that is dominated by a handful of very large firms. In the world imaging industry, technological breakthroughs, such as the CT scanner and MRI machine, were not introduced by established producers of X rays, but rather by a new breed of innovators. Yet, first-mover advantages do not seem to have been very significant and, as we will see, these new entrants failed to sustain themselves over time. In fact, established American and European X-ray companies have remained leaders in the imaging industry, with Japanese firms starting to play a more prominent role in the international arena only in recent years.