雅思阅读材料：Reviving autopsy

　　The scans were far from perfect. The rate of discrepancy between the cause of death, as determined by radiology and as determined by conventional autopsy, was 32% for CT scans, 43% for MRI and 30% for a combination of CT and MRI. Most troubling, the scans had difficulty showing heart disease, a common killer. However, radiologists were good at identifying which diagnoses were sound and which needed to be re-evaluated by a full autopsy. When they felt confident in their diagnoses—which was the case for 34% of CT investigations and 42% of MRIs—the discrepancy between the results from scanning and those from autopsies was lower. For CT scans, it was just 16%.

　　That is still a significant gap, of course. But not all of it is caused because traditional methods are better. For one body, for example, scanning revealed a lethal stroke that dissection missed.All this suggests that scans might play a useful role in determining causes of death. When a radiologist is confident in the diagnosis from a scan, a traditional autopsy might be unnecessary. When he is less confident, his scan could still be a useful guide for the wielder of the knife.

　　Automating autopsies by using scanners might also make them cheaper, by speeding the process up. And it could be done with otherwise-redundant machines that have been replaced for use on live patients with modern devices which give off less radiation. That would get rid of the need to buy new kit to cope with the extra demand for scans. A thorough study of the costs of both approaches would be needed, of course, and traditional autopsies are unlikely to disappear completely. But for some deaths, a scan will likely prove better than a scalpel.