Ultrasound Glossary

Narrowing of the carotid artery, usually from plaque buildup, that reduces blood flow to the brain and increases the risk of stroke.

A common condition caused by compression of the median nerve in the wrist, which can be diagnosed using musculoskeletal ultrasound.

The most common benign tumor of the liver, appearing on ultrasound as a bright, well-defined mass with characteristic features.

Cardiovascular Credentialing International — a credentialing body offering the RCS and RCCS credentials for cardiac sonographers.

The beginning of the large intestine, located in the lower right abdomen, where the appendix is attached.

The first major branch of the abdominal aorta that supplies blood to the stomach, liver, spleen, and pancreas.

The short arterial segment that branches from the aorta and immediately divides to supply the upper abdominal organs.

A superficial vein running along the outer side of the arm that is commonly used for IV access and evaluated during upper extremity venous ultrasound.

A birth defect in which brain tissue or its covering membranes protrude through an opening in the skull, detectable on prenatal ultrasound.

The part of the brain located at the back of the skull that coordinates movement and balance, routinely measured during prenatal and neonatal ultrasound.

A weak, ballooning area in a brain artery that carries a risk of rupture, which can be monitored indirectly with transcranial Doppler.

Any of the major arteries supplying blood to the brain, which can be assessed for flow abnormalities using transcranial Doppler ultrasound.

Shrinkage or loss of brain tissue that results in enlarged ventricles and widened spaces between the brain’s folds, visible on cranial ultrasound.

Swelling of the brain due to excess fluid accumulation, which can be detected on neonatal cranial ultrasound as increased echogenicity of the brain tissue.

Bleeding within the brain that can occur in premature infants, trauma patients, and stroke victims, readily detected with ultrasound in newborns.

Death of brain tissue due to loss of blood supply, commonly known as a stroke, which can sometimes be detected with ultrasound in newborns.

A group of disorders affecting movement and posture caused by brain damage that occurs before, during, or shortly after birth.

One of two thick bundles of nerve fibers connecting the cerebrum to the brainstem, identifiable on neonatal cranial ultrasound.

The clear fluid that surrounds and cushions the brain and spinal cord, appearing as dark (anechoic) areas within the ventricles on cranial ultrasound.

The medical term for a stroke, which occurs when blood flow to part of the brain is interrupted, and can be prevented through carotid ultrasound screening.

The largest part of the brain, divided into two hemispheres, responsible for thought, movement, and sensation, evaluated in neonatal cranial ultrasound.

A stitch placed around the cervix during pregnancy to help keep it closed and prevent premature delivery, monitored with ultrasound.

A condition in which the cervix begins to open too early during pregnancy, which can lead to premature delivery and is monitored with transvaginal ultrasound.

The measurement of the cervix from the internal to the external opening, performed with transvaginal ultrasound to assess the risk of preterm birth.

A small, bean-shaped immune system organ in the neck that can become enlarged due to infection, inflammation, or cancer, and is easily evaluated with ultrasound.

Inflammation of the cervix, often caused by infection, which can be assessed with transvaginal ultrasound.

The lower, narrow portion of the uterus that connects to the vagina, routinely evaluated with ultrasound during pregnancy and gynecological examinations.

A structural defect in the back of the skull that causes brain tissue to extend into the spinal canal, sometimes detectable on prenatal or neonatal ultrasound.

A type of ovarian cyst filled with old, dark blood from endometriosis, named for its resemblance to melted chocolate.

A cancer arising from the cells lining the bile ducts, which can cause bile duct dilation detectable on ultrasound.

An imaging procedure that visualizes the bile ducts, typically using contrast dye, to detect stones, tumors, or other blockages.

A serious infection of the bile duct system, usually caused by a blockage, that can be evaluated with ultrasound.

Inflammation of the gallbladder, most commonly caused by gallstones — diagnosed on ultrasound by wall thickening, pericholecystic fluid, and sonographic Murphy sign.

A severe, life-threatening form of gallbladder inflammation caused by gas-forming bacteria, showing gas within the gallbladder wall on ultrasound.

A hormone that causes the gallbladder to contract and release bile, sometimes used during ultrasound studies to test gallbladder function.

A congenital dilation of the bile ducts that can be detected on prenatal or postnatal ultrasound and may require surgical treatment.

Gallstones within the common bile duct, identified on ultrasound by hyperechoic shadowing foci within a dilated duct.

The medical term for gallstones, which are one of the most common findings on abdominal ultrasound.

A condition in which the flow of bile from the liver is slowed or blocked, which may cause bile duct dilation visible on ultrasound.

Thin, cord-like structures that connect the heart valve leaflets to the papillary muscles, preventing the valves from turning inside out during contraction.

End-stage liver fibrosis characterized on ultrasound by a coarsened echotexture, nodular surface, and signs of portal hypertension.

A Doppler mode that overlays color-coded blood flow direction and velocity onto a 2D B-Mode image in real time.

An ultrasound technique that displays blood flow as colors on top of a grayscale image. Red typically means blood flowing toward the transducer and blue means blood flowing away.

A Doppler mode using two crystals to continuously transmit and receive, capable of measuring very high blood flow velocities without aliasing.

An imaginary line that divides the body from top to bottom, creating front and back halves. A coronal scan shows a front view of the body.

A temporary endocrine structure formed in the ovary after ovulation, appearing on ultrasound as a thick-walled cystic structure with peripheral vascularity.

The measurement from the top of the fetal head to the bottom of the torso, used to date a pregnancy in the first trimester.

A transducer with a curved face that produces a fan-shaped image, used for abdominal and obstetric imaging.