雅思阅读材料：Reviving autopsy

TECHNOLOGY advances not only through new inventions, but also by theimaginative application of old ones. And one of the most ancient forms ofscientific investigation, the post-mortem autopsy, may be ripe for just such atechnological upgrade. According to a paper in this week’s Lancet, published byIan Roberts of the John Radcliffe Hospital, in Oxford, it may soon be time toput away the scalpel and the retractor clamp, and to replace them with the bodyscanner.

The study of death is never a cheerful topic, but it has gone through aparticularly gloomy patch over the past few decades. A recent tally by America’sCentres for Disease Control and Prevention showed that in 2007 only 8.5% ofdeaths in America were investigated by autopsy. In 1972 that figure was 19.3%.Britain’s coroners are more active, but perhaps not more accurate. Twenty-twopercent of deaths in the United Kingdom lead to an autopsy. According to agovernment review, however, one in four is of miserable quality. The upshot inboth cases is not just that the cause of inpidual deaths may be misascribed.More seriously, data about the processes of disease are lost, and those diseasesare thus not as well understood as they might have been. Squeamish relatives ofthe deceased, too, often do not like the idea of bodies being cut up at thebehest of coroners. Britain’s health department therefore commissioned DrRoberts to study whether scanning dead bodies in the way that is routine forliving ones would help. His conclusion is that it would.

Rather than slicing the body with a knife, scanning slices them withradiation. Computerised tomography (CT) uses X-rays to collect information frommany angles, and a lot of processing power to convert that information intocross-sectional images of a body’s inner tissues. In forensic cases CT scans areoften used to spot fractures and haemorrhages. Dr Roberts found them adept atnoticing diseased arteries, as well. The other widespread scanning technique,magnetic-resonance imaging (MRI), uses radio waves and is best suited forexploring the detail of soft tissues.

Though both of these technologies have been around for a long time, theyhave had only limited use in autopsies. America’s authorities conduct CT scansof dead soldiers—but such scans are employed to augment traditional postmortems, not replace them. Some coroners in England, spurred on by the religiousobjections of Jews and Muslims, do allow scans rather than conventionalautopsies in certain cases. But the accuracy of these scans is unknown. DrRoberts is the first to provide data on whether scanning might replaceconventional methods.

He and his colleagues examined 182 bodies in Manchester and Oxford.Radiologists studied CT and MRI scans of these bodies, made diagnoses based onthem, explained their confidence in these diagnoses, and judged whether thescans might thus preclude the need for a full autopsy. Within 12 hours of eachscan, a pathologist then performed a conventional autopsy, so that Dr Robertscould compare the new methods with the old.