How is a pulmonary embolism diagnosed?
Pulmonary embolism can be diagnosed with what's called a VQ Scan which is a special kind of scan. You can do a pulmonary angiogram which is a quite invasive procedure where you have to put a catheter into a vein, slide it on up into the right side of the heart and then inject some dye into the pulmonary artery. As that dye goes out (it is dye that doesn't really colour anything, but it is dye as far as the radiographic tube is concerned) it shows the outline of that clot. However, the more preferred way these days is to do a very high tech type of CT Scan; the computerized thermography, and it is non-invasive, quite quickly done and has become pretty much the gold standard these days of diagnosing pulmonary embolism. When you want to really make it difficult for medical students, you can ask them, "What is the most common finding on a chest X-ray; the plain, early, usual, chest X-ray, for pulmonary embolism?" and the answer to that question is normal. So, the normal chest X-ray can be seen frequently on the initial radiographic evaluation of pulmonary embolism. Most of the time students don't get that so it's fun to ask that question.
