What are other uses for CT in the setting of pulmonary embolism?
CT also can be used to evaluate the lower extremity venous system for thrombosis, using the same contrast bolus, by imaging the lower extremities shortly after the thoracic scan has been performed. Lower extremity ultrasonography (US) is generally used to evaluate the lower extremity veins for deep venous thrombosis (DVT), but CT has several advantages. One is that it is operator independent, in contrast to US. CT can also be used to evaluate for DVT in areas that are inaccessible to US or difficult to evaluate. This includes the deep pelvic veins (a common source of thrombus that may embolize to the lungs) and the region near the adductor canal. Furthermore, US is more limited in patients who are obese or who have had recent surgery.
