In this bachelor thesis we will process a CT scan of pulmonary arteries in suspected pulmonary embolism, a disease that usually affects older people, but is not and expection among younger people, especially women. At the beginning we describe anatomy of the lungs and pulmonary blood vessels, organs without which life is impossible, as a distinct importance to be healthy and functioanl. Pathology and pathophysiology of pulmonary embolism and CT imaging of pulmonary arteries will be explained in detail. Compare the various protocols with 16 and 64 row detectors, as well as protocols and measurment of application of contrast medium in the blood vessel. We will explain the most common reconstructive parameters we use in the diagnosis of pulmonary embolism, artifacts that may occur and compare CT pulmonary angiography with other techniques which use, their advantages and disadvantages.