Nerve

Nerves are composed of bundles of nerve fibers (axons) surrounded by connective tissue coverings called fascia. On ultrasound, nerves appear as hypoechoic to isoechoic structures with characteristic fascicular echotexture visible on transverse imaging, appearing as hypoechoic dots surrounded by echogenic connective tissue, resembling a honeycomb or honeybee pattern. On longitudinal imaging, nerves appear as parallel hypoechoic linear structures. Peripheral nerve ultrasound has become an important diagnostic tool for conditions such as carpal tunnel syndrome, where the median nerve can be visualized and measured at the wrist. Ultrasound is also increasingly used for nerve blocks and other interventional procedures, and dynamic imaging can assess nerve movement.