Ultrasound Database •
In power mode the amplitude (power) of color Doppler signals is displayed, regardless of the velocity. Power does not have negative values and is independent of sampling frequency. An aliasing artifact does not occur in power mode images. Caused by plotting the quantity enhanced by echo contrast agents in a power map, power mode is often used in contrast Doppler ultrasound examinations. Also known as energy mode. • View NEWS results for 'Power Mode' (3). ![]() •
Power modulation is a non-linear method, based on a multi-pulse technique where the acoustic amplitude (and hence power) of the transmitted pulses is changed. Full and half amplitudes pulses are used to induce changes in the response of the contrast agent. The received echoes from the emitted half amplitude pulse are adjusted with the full amplitude pulse and this pairs of pulses are subtracted. Power modulation is used to separate contrast agent echoes at low mechanical index, allowing real-time perfusion imaging. Power modulation can be used with a low frequency wide band transducer to increase the depth and transmit the sound beam homogenous allowing ultraharmonic imaging. ![]() Further Reading: News & More:
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Pregnancy ultrasound plays a crucial role in monitoring the health and development of the fetus throughout pregnancy. It serves as a screening tool with various applications, including:
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Verification of Due Date and Assessment of Pregnancy Health: Fetal ultrasound examinations are used to accurately determine the estimated due date of the baby. They also aid in investigating the causes of bleeding during pregnancy and assessing the overall health and well-being of the fetus. •
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Measurement of Amniotic Fluid and Placental Assessment: Ultrasound is utilized to measure the amniotic fluid levels, which provide insights into fetal well-being and the functioning of the placenta. It also helps evaluate the condition of the placenta, ensuring proper nutrient and oxygen supply to the developing baby. •
Early Pregnancy Confirmation and Multiple Fetuses Detection: Around week five to seven of pregnancy, ultrasound is utilized to confirm the pregnancy, determine the fetal size, and detect the presence of multiple fetuses. It aids in distinguishing between intrauterine and ectopic pregnancies, ensuring appropriate management. •
Third-Trimester Evaluation: As the pregnancy progresses, ultrasound assessments are conducted to evaluate fetal size, position, growth, and the condition of the placenta. This information assists healthcare providers in monitoring the well-being of the fetus and planning for a safe delivery. •
Guiding Procedures: Ultrasound plays a vital role in guiding invasive procedures such as amniocentesis and chorionic villus sampling. It helps guide the placement of a needle to collect cells from the amniotic fluid or placenta, aiding in genetic testing and diagnosing potential fetal abnormalities. See also Doppler Fluximetry in Pregnancy, Fetal Ultrasound, Obstetric and Gynecologic Ultrasound and Vaginal Probe. • View NEWS results for 'Pregnancy Ultrasound' (6). ![]() •
Pressure is the force per unit area applied on a surface in a direction perpendicular to that surface. Pressure can also be described as a form of potential energy in a fluid. The maximum pressure of the fluid medium obtained during propagation of an ultrasonic pulse. The negative peak pressure is the peak rarefaction pressure attained during the negative portion of a propagating ultrasound pulse in a medium such as tissue. Sound pressure can be measured using a microphone in air and a hydrophone in water. The SI unit for sound pressure is the Pascal. Blood pressure is the pressure exerted by the blood on the walls of the blood vessels. See also Rarefactional Pressure, Low Intensity Pulsed Ultrasound, and Projector. • View NEWS results for 'Pressure' (6). ![]() •
Printers can be used to capture a hard copy of the image from the display of the ultrasound machine.
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