What is the definition or description of: serial ultrasound?

Repeat ultrasounds: Used to monitor progression or resolution of pathology such as size of a cyst or a mass.. For instance to see if a cyst is enlarging or getting smaller, or in others response to chemotherapy.

Several ultrasounds: Sometimes to make a clear diagnosis, one ultrasound is not enough. Two or more ultrasounds at different points in time may be needed. This allows the doctor to see if things are changing or staying the same, which may be necessary for a proper diagnosis.