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In medical dramas, all a doctor has to do is look at an x-ray, CT scan, or an MRI to make a Lethal Diagnosis. It doesn't matter who the doctor is, what their specialty is, or even if they're treating the patient. The moment they hold the sheet of film up to the lighttable their facial expression changes. This may involve a condition that is lethal and virtually untreatable like advanced stage cancer, or something that needs urgent attention like an aortic dissection. In more modern works, the doctor may be standing in the radiology control room as the images are shot, with the same horrified expression as the images result on the technologist's workstation. A subtrope of Lethal Diagnosis.