What can ultrasound tell us?

UCSF ultrasound Radiologist Dr. Callen describes various purposes of diagnostic ultrasound, from screening disease to treating it.  We can use ultrasound guidance to place a needle in a mass to detect if it is a tumor or something else by testing that sample with a pathologist.  Ultrasound guidance is frequently used in the emergency room when the patient has leg pain and is concerned about a clot (deep venous thrombosis).  Ultrasound is done on the lower extremity artery, if the vein is compressing nicely then there is no evidence of clot. If there is a clot, then the vein is the same and will not compress which indicates a clot.