The CT scan revolutionized medical diagnosis,allowing doctors,for instance,to see if a head injury had produced any bleeding in the brain or to make out the shape and extent of tumors in cancer patients.

• 计算机X射线断层造影术扫描是医学诊断上的一次革命，它使医生可以检查到脑伤是否引起脑内出血，或者了解癌症病人肿瘤的形状和范围。