Ultrasound Glossary

Swelling caused by excess fluid trapped in body tissues, which appears on ultrasound as increased fluid surrounding or within affected structures.

A narrow, dark artifact that appears on ultrasound at the curved edges of round structures like cysts, caused by the sound beam bending as it passes by.

Thin shadows at the lateral edges of curved structures such as cysts, caused by refraction at the curved surface.

A measurement of cardiac function representing the percentage of blood pumped out of the left ventricle with each heartbeat.

The ability of tissue to return to its original shape after being compressed or stretched, which varies between normal and diseased tissue.

An ultrasound technique that maps tissue stiffness, used to assess liver fibrosis and characterize breast and thyroid lesions.

The joint connecting the upper arm to the forearm, commonly evaluated with musculoskeletal ultrasound for injuries and inflammatory conditions.

The developing human organism from fertilization through the eighth week of pregnancy, visible on early transvaginal ultrasound.

An infection of the inner lining of the heart, usually affecting the valves, which produces growths called vegetations visible on echocardiography.

The thin, smooth inner lining of the heart chambers that can be evaluated during echocardiography.

A probe designed for insertion into body cavities such as the vagina or rectum to obtain high-resolution images of nearby organs.

Cancer of the uterine lining, most commonly detected when ultrasound reveals abnormal thickening of the endometrium in a postmenopausal woman.

Abnormal thickening of the uterine lining from excessive cell growth, which can be a precursor to endometrial cancer and is evaluated with ultrasound.

A growth attached to the inner wall of the uterus that can cause abnormal bleeding and is well visualized with transvaginal ultrasound.

The thin, bright line seen on ultrasound that represents the two layers of the uterine lining pressed together, measured to assess uterine health.

The sonographic measurement of the endometrial lining, used to evaluate postmenopausal bleeding and monitor ovulation.

An ovarian cyst filled with old menstrual blood from endometriosis, characterized by a distinctive ground-glass appearance on ultrasound.

A condition in which tissue similar to the uterine lining grows outside the uterus, causing pain and infertility, with ovarian involvement visible on ultrasound.

The inner lining of the uterus that thickens each month in preparation for pregnancy and is shed during menstruation, routinely evaluated with transvaginal ultrasound.

An ultrasound technique in which a small transducer is placed inside the body through a natural opening to get closer to the structure being examined.

An ultrasound examination performed using a specially designed probe inserted into the vagina, providing detailed images of the uterus, ovaries, and early pregnancy.

An increase in the brightness of echoes behind a structure that transmits sound well, such as a fluid-filled cyst, helping to confirm its fluid content.

A coiled tube on the back of each testicle that stores and transports sperm, commonly evaluated with scrotal ultrasound.

Inflammation of the epididymis, usually caused by bacterial infection, which causes pain and swelling detectable on scrotal ultrasound.

A collection of blood between the skull and the brain’s outer covering, typically caused by head trauma, which can be life-threatening.

Inflammation of small fat-filled pouches on the outer surface of the colon that can mimic appendicitis or diverticulitis on clinical examination.

A rare congenital defect in which the urethral opening is on the top surface of the penis rather than at the tip.

A birth defect in which the esophagus does not connect to the stomach, which may be suspected on prenatal ultrasound when the fetal stomach is not visible.

Cancer of the esophagus, which can be staged using endoscopic ultrasound to assess tumor depth and lymph node involvement.

Enlarged veins in the esophagus caused by liver disease and portal hypertension, which carry a risk of life-threatening bleeding.

The muscular tube connecting the throat to the stomach, which is primarily evaluated in sonography through transesophageal echocardiography.

A calculation derived from ultrasound measurements of the fetal head, abdomen, and femur, used to assess whether a fetus is growing normally.

The bile ducts and gallbladder located outside the liver that collect and transport bile to the intestine, routinely evaluated during abdominal ultrasound.

One of two slender tubes that connect the ovaries to the uterus, through which eggs travel after ovulation, sometimes visible on ultrasound.

An abnormal channel created within the wall of a blood vessel when blood forces its way between the layers of the vessel wall during a dissection.

The region beyond the focal zone where the ultrasound beam begins to diverge, reducing lateral resolution.

Focused Assessment with Sonography for Trauma — a rapid bedside ultrasound protocol to detect free fluid and pericardial effusion in trauma patients.

The accumulation of fat within the cells of an organ, most commonly the liver, which changes its appearance on ultrasound.

Accumulation of fat within liver cells, appearing as increased echogenicity of the liver parenchyma on ultrasound.

The major artery of the thigh that supplies blood to the leg, one of the most important vessels evaluated in peripheral arterial ultrasound.

The ball-shaped top of the thighbone that fits into the hip socket, a key structure evaluated in infant hip ultrasound.

The narrow section of the thighbone connecting the femoral head to the shaft, commonly affected by fractures in elderly patients.

The major deep vein of the thigh that carries blood back to the heart, one of the most commonly evaluated vessels in venous ultrasound.

The thighbone, the longest and strongest bone in the body, whose length is measured as a standard part of obstetric ultrasound.

A standard ultrasound measurement of the fetal thighbone used to estimate gestational age and calculate fetal weight.

Standardized ultrasound measurements of the fetus used to estimate gestational age, assess growth, and calculate estimated fetal weight.

The unique pattern of blood flow in an unborn baby that bypasses the lungs and uses the placenta for oxygen exchange.

A specialized ultrasound examination of the fetal heart used to detect congenital heart defects before birth.

A condition in which a fetus does not grow to its expected size during pregnancy, monitored closely with serial ultrasound examinations.

The number of times the fetal heart beats per minute, normally between 110 and 160 beats per minute, assessed during every obstetric ultrasound.