摘要: Ultrasonography is a safe and commonly applied imaging technique for the study of soft tissues in the human body. Real-time feedback on anatomic images is the main strength of ultrasound imaging. Physically, ultrasound refers to mechanical vibrations in media with frequencies beyond the upper limit of normal human hearing (20 kHz). During ultrasonography ultrasonic waves with frequencies ranging from 1 to 20 MHz are applied to the skin by a probe that contains an electromechanical transducer. This transducer consists of piezoelectric crystals that characteristically operate both as a transmitter and a receiver. The transducer converts electrical signals into mechanical vibrations (ultrasonic waves) that are transmitted into the underlying tissues. A part of the ultrasonic wave is reflected at the boundaries of different tissues and subsequently received by the transducer again. As the average velocity of sound through various soft tissues is relatively constant (1540 m/s), further signal analysis can be based on the time interval between transmitting and receiving the signal by the transducer. Although many physicians still think that sonographic pictures are difficult to interpret, the image quality has improved considerably over the past decade. For neuromuscular ultrasound, technologic advances have even made it possible to depict small parts like peripheral nerves with excellent resolution, commonly referred to as high-resolution ultrasonography. There is a growing interest in high-resolution ultrasonography as a diagnostic tool for diseases of the peripheral nervous system, probably because of these new technologies. Over the past 15 years …