It sounds like someone had an ultrasound of their abdomen and you are reading the radiologist's report of the scan. Often these reports can be confusing because they use terms that are not completely clear. In this case, a hypoechoic mass is simply just an object inside the abdomen which does not bounce back sound waves (echo) as well as its surrounding tissue. Without knowing more about the patient, their symptoms, their past medical history, and their physical exam findings, it is hard to say more than that. This mass could be one of many different things. A hypoechoic mass could be a pocket of blood around an injury. It could be a cyst coming from the liver. It could be tumor arising from one of the abdominal structures near the left lobe of the liver. Whatever it is, it will probably need to be imaged again with a CAT scan to better determine what it likely is.
Please schedule an appointment with your primary care physician
, or whoever ordered the ultrasound. He or she can look at the ultrasound images, read the report, and perform a full physical exam. Your doctor
may be able to determine from this what this mass is, or at least know what test would be prudent to get next. Good luck.