KNOBOLOGY

Peripheral nerves are made up of multiple nerve fibers that are organized into bundles called fascicles. When a nerve is examined using ultrasound, the scan shows several small, hypoechoic “bubbles” within the larger, hyperechoic epineurium. These bubbles represent the fascicles and have a honeycomb-like structure. It is important to be able to recognize this organized structure in order to distinguish it from a tendon, which has a fibrillar structure rather than fascicles.