History of Diagnostic Medical Sonography and Professional Practice

Comprehensive vocabulary and key concepts from the history of medical sonography, physical properties of sound, and professional sonography standards.

Sound

A vibration (compression and rarefaction) that propagates as an audible wave of pressure through a medium.

Speed of sound in Soft tissue

$$1540\,m/s$$

Audible sound range

Sound ranging between $20\,Hz$ and $20,000\,Hz$ ($20\,kHz$).

Infrasound

Sound below $20\,Hz$, which is below the range of human hearing.

Ultrasound

Sound frequencies greater than $20,000\,Hz$.

Clinical ultrasound frequency range

Ultrasound frequency typically ranging between $2\,MHz$ and $15\,MHz$.

Sonography

The technique that uses sound waves in the form of ultrasound to produce images called sonograms.

Sonogram

The image produced by the ultrasound machine.

Wilhelm Rontgen

Discovered X-Ray in $1895$, the first imaging modality.

Georg Charles de Hevesy

Researched Nuclear Medicine in $1923$, the second imaging modality.

Isaac Newton (speed of sound contribution)

Determined the speed of sound in air to be $343\,m/s$ in the early $18th$ century.

Piezoelectric effect

The ability of certain crystals to expand and contract to create and receive sound, discovered by Jacque and Pierre Curie in $1880$.

Hydrophone

A device built by Paul Langevin in $1915$ using piezoelectric properties of quartz to detect underwater objects like submarines.

George Ludwig

Used pulse-echo ultrasound in the $1940s$ to detect gallstones in animals.

John Wild

Considered the father of medical ultrasound; first to use ultrasound to detect tissue thickness and co-developed B-mode techniques.

B-mode

Brightness modulation techniques using $2D$ presentations of echo-producing interfaces.

M-mode

Motion modulation; a technique showing a continuous moving display of returning echoes used to evaluate heart valve motion.

Ian Donald

Discovered the first diagnostic applications of ultrasound, refined obstetric techniques, and identified the importance of a full bladder for pelvic visualization.

Grayscale imaging

Developed by Kossoff in $1973$ using a scan converter to process echoes as different shades of gray based on intensity.

Duplex Doppler

An $1980's$ technology requiring precise angle correction that combines Doppler with an image.

Power Doppler

A $1990's$ technology more sensitive than color Doppler that does not show flow direction.

Lithotripsy

A therapeutic application using high-power ultrasound to shatter stones, such as kidney stones, into smaller pieces.

Technician

A person with $6$ weeks to $6$ months of education beyond high school.

Sonologist

Any physician who interprets an ultrasound study, most commonly a Radiologist.

SDMS

Society of Diagnostic Medical Sonography; formerly the AUTS, renamed in $2001$.

ARDMS

American Registry of Diagnostic Medical Sonography, incorporated in $1975$ to administer credential tests.

RDMS (AB)

Registered Diagnostic Sonographer specializing in Abdomen.

RVT

Registered Vascular Technologist.

RDCS

Registered Diagnostic Cardiac Sonography.

ARDMS CME requirements

After registry, sonographers must earn $30$ CME credits in a three-year period.