Ultrasound Physics and Imaging Modalities Review

Vocabulary flashcards reviewing core imaging modalities, transducer types, acoustic properties, and historical ultrasound discoveries.

Radiation-Based Imaging Modalities

The three imaging modalities that utilize radiation to create an image: CT, X-ray, and nuclear medicine.

MRI

An imaging modality that does not use radiation at all to create an image.

Modalities Demonstrating Organ Function

Imaging modalities that evaluate the functioning of an organ, specifically nuclear medicine and ultrasound (such as evaluating the pumping of the heart).

A-mode

Amplitude mode in ultrasound, which measures echo amplitude rather than displaying a waveform.

Pulse Doppler

An ultrasound modality that produces a waveform.

Continuous Wave Doppler

An ultrasound modality that generates a waveform display.

Speed of Ultrasound in Tissue

The velocity of ultrasound propagation through soft tissue, defined as $1,540\,\text{m/s}$.

Reflection

The component of attenuation that creates an ultrasound image when sound beams strike an acoustic interface and bounce back to the transducer.

Linear Transducer

A transducer operating at high frequencies that provides high resolution with low penetration; optimal for superficial structures close to the skin surface, such as the thyroid.

Curvilinear Transducer

A transducer operating at lower frequencies to provide deeper penetration at the expense of resolution; primarily utilized for abdominal and OB imaging.

Sector Transducer

A lower-frequency transducer with a small footprint designed to fit between rib intercostal spaces to image deep structures like the heart in cardiac imaging.

Piezoelectric Effect

The scientific principle discovered by the Curie Brothers in 1880 that serves as a foundation for ultrasound transducers.

Christian Doppler

The scientist who discovered the Doppler principle in 1842.

Ultrasound Technological Precursors

The foundational technological developments that contributed to ultrasound machines, specifically sonar, radar, and metal wall detectors.