Ultrasound Glossary

Ultrasound that acquires a volumetric dataset allowing reconstruction in multiple planes and surface-rendered views.

A real-time, moving version of 3D ultrasound that shows live motion of structures like a developing fetus.

A horizontal, repeating artifact seen on lung ultrasound that indicates normal, air-filled lung tissue.

The simplest ultrasound display mode, showing a single line of echo amplitude as spikes on a graph.

The large artery that runs through the abdomen, carrying oxygen-rich blood from the heart to the lower body.

An abnormal bulge or widening of the abdominal aorta that can be life-threatening if it ruptures.

A localized collection of pus caused by infection, which appears on ultrasound as a fluid-filled area with irregular walls.

Inflammation of the gallbladder that occurs without gallstones, often seen in critically ill patients.

A small, extra piece of splenic tissue found near the main spleen, present in about 10 to 15 percent of people.

A tissue property that determines how much ultrasound energy is reflected at boundaries between different tissues.

A technique using focused ultrasound pulses to mechanically displace tissue and measure the resulting tissue response for stiffness assessment.

A dark area on an ultrasound image that appears behind a dense structure like a gallstone or bone, where the sound beam has been blocked.

A dark shadow deep to a highly reflective or absorptive structure such as a calcification or gas pocket.

A region of the body that allows unobstructed passage of ultrasound waves to the structure being imaged.

A hormonal disorder caused by excess growth hormone, which leads to enlarged bones and organs that may be detected during ultrasound examinations.

Sudden inflammation of the gallbladder, usually caused by a gallstone blocking the cystic duct, and one of the most common reasons for an abdominal ultrasound.

A sudden decline in kidney function that can be evaluated with ultrasound to check for obstruction or other structural causes.

Sudden inflammation of the pancreas, often caused by gallstones or alcohol use, that can be evaluated with ultrasound.

A bacterial infection of the kidney that can cause swelling, abscess formation, and changes visible on ultrasound.

A benign tumor that develops from glandular tissue and can occur in organs like the liver, thyroid, adrenal glands, and parathyroid glands.

A condition in which the tissue that normally lines the uterus grows into the muscular wall, causing pain and heavy menstrual bleeding.

The structures located next to the uterus, including the ovaries, fallopian tubes, and surrounding ligaments.

A gynecological emergency in which the ovary or fallopian tube twists on its blood supply, cutting off circulation.

The complete absence of an organ or structure from birth due to failure of that organ to develop during fetal growth.

The complete absence of movement in a segment of the heart wall, often indicating severe damage from a heart attack.

As Low As Reasonably Achievable — the guiding principle of ultrasound safety, directing sonographers to use the minimum acoustic output needed for diagnosis.

A Doppler artifact where high-velocity flow wraps around the velocity scale, producing ambiguous direction display.

A measurement used in infant hip ultrasound to assess the depth of the bony socket that holds the femoral head.

The clear fluid that surrounds and protects the developing fetus inside the uterus throughout pregnancy.

A sonographic measurement of amniotic fluid volume calculated by summing the largest fluid pockets in four uterine quadrants.

The small opening where the common bile duct and pancreatic duct join and empty into the duodenum.

A highly aggressive, fast-growing cancer most commonly found in the thyroid gland, with a distinctive ultrasound appearance.

Appearing completely black on ultrasound with no internal echoes, characteristic of simple fluid.

A condition in which the blood has fewer red blood cells or less hemoglobin than normal, which can be assessed in a fetus using Doppler ultrasound.

A severe birth defect in which a major portion of the brain and skull fails to develop, detectable by ultrasound early in pregnancy.

An abnormal, permanent widening or bulging of a blood vessel wall, commonly detected and monitored using ultrasound.

Abnormal, fragile blood vessels in the wall of the gastrointestinal tract that can cause bleeding.

A benign tumor made up of blood vessels or lymph vessels, commonly found in the liver as a hemangioma.

An artifact in musculoskeletal ultrasound where a tendon appears falsely hypoechoic when the beam is not perpendicular to its fibers.

A ratio of blood pressure at the ankle to the arm, used to screen for peripheral arterial disease — often performed alongside vascular ultrasound.

A type of ultrasound transducer design that arranges its crystal elements in concentric rings to improve focusing of the sound beam.

The tough outer ring of a spinal disc that contains the softer inner material and can be evaluated with musculoskeletal ultrasound.

A major blood vessel supplying the front portion of the brain, which can be evaluated using transcranial Doppler ultrasound.

A bundle of nerve fibers connecting the two hemispheres of the brain, visible on neonatal cranial ultrasound.

The soft spot on the top of a baby’s head that serves as the primary acoustic window for neonatal cranial ultrasound.

The front portion of the lateral ventricle of the brain, routinely measured during neonatal cranial ultrasound.

A chamber or cavity in the body, most commonly referring to the lower portion of the stomach or the cavity within an ovarian follicle.

The largest artery in the body, carrying oxygen-rich blood from the heart to all other organs, and one of the most commonly evaluated structures in abdominal ultrasound.

Permanent dilation of the aorta to 1.5 times its normal diameter or greater — the abdominal aorta is screened with ultrasound in high-risk populations.

The curved upper portion of the aorta that gives rise to the major arteries supplying the head, neck, and arms.