Ultrasound

Visualization of structures in the body by recording the reflections of sound waves directed into tissues. May be used during surgery. Also called ultrasound scanning or sonography, uses high-frequency sound waves to obtain images inside the body. Neurosonography...

Undifferentiated

An immature, embryonic, or primitive cell. It has a nonspecific appearance with multiple nonspecific activities and functions poorly. See differentiate, dedifferentiate. In cancer, refers to how mature (developed) the cancer cells are in a tumor. Differentiated tumor...