History of Diagnostic Medical Sonography and Sonographers

History of Diagnostic Medical Sonography and Sonographers

What is Ultrasound?

  • Ultrasound refers to sound frequencies beyond the range of normal human hearing, specifically above 20 kHz.
  • Normal human hearing ranges from 20 Hz to 20 kHz.

Applications of Ultrasound

  • Non-medical Applications:
    • Automatic door openers
    • Detecting flaws in metals
    • Sonar: Locating objects under water and determining distance
  • Medical Applications:
    • Diagnostic
    • Therapeutic
    • Physical and occupational therapy: Increasing blood flow to speed up healing and creating warmth in tissues.
    • Lithotripsy: Breaking up gallstones, kidney stones, and heel spurs using high power levels.
    • Diagnostic ultrasound: The most common medical application.

Terminology

  • Ultrasound: Broad term encompassing medical and non-medical uses of sound waves, including therapeutic and diagnostic applications.
  • Sonography: Specifically refers to the diagnostic imaging application of ultrasound.
  • Ultrasonography: A synonym for sonography.

A Brief History of Sonography

  • Sonography is the third oldest imaging modality.
  • 1880: Jacque and Pierre Curie
    • Discovered the piezoelectric effect, enabling the construction of transducers to generate and receive sound waves in water.
  • 1915: Paul Langevin
    • Invented a sonar-type device using echolocation to detect submarines.
  • 1940s: Dr. George Ludwig
    • Detected gallstones using ultrasound.
  • Dr. John Wild
    • First to use ultrasound to detect tissue thickness.
    • Pioneer in developing early internal scanners.
    • Constructed an early prototype breast scanner with engineer John Reid.
    • Wild and Reid's B-mode (brightness modulation) techniques used 2D presentations of echo-producing interfaces.
  • 1953: Drs. Edler and Hertz
    • Explored ultrasound in the heart, adding a continuous moving display of returning echoes (M-mode) to evaluate heart valve motion.
  • Ian Donald
    • Credited with discovering the first diagnostic applications of ultrasound.
    • Refined techniques for obstetric procedures.
    • Discovered the importance of a full bladder for visualizing pelvic structures.
  • 1962: Holmes, Wright, and Meyerdirk
    • Developed the first compound contact B-mode scanner.
  • Physicist George Kossoff
    • Developed a new scan converter to process returning echoes and display them as different shades of gray based on intensity (grayscale imaging).
  • Engineer Martin H. Wilcox
    • Founded Advanced Diagnostic Research (ADR) Corporation to refine real-time ultrasound machines.
  • Mid-1980s
    • New and improved real-time equipment became available, replacing static B-scanners.
    • The ultrasound field continued to grow with the development of new transducer technologies.

A Brief History of Doppler

  • Donald Baker
    • Designed sophisticated, implantable flowmeters.
  • Baker, Dr. Rushmer, and Dean Franklin
    • Developed a small, hand-held, portable, continuous-wave Doppler device for transcutaneous use.
  • Dr. Eugene Strandess
    • Developed noninvasive measuring of the peripheral vascular system; his 1967 publication assigned particular waveforms to specific disease conditions.
  • 1970: Baker and Watkins
    • Developed the first pulsed Doppler unit.

The Doppler Revolution

  • Baker
    • Developed a technique for determining blood flow volume from Doppler velocimetry measurements.
  • The Seattle group (1974)
    • Developed the first pulsed-Doppler scanner capable of combining with 2D gray-scale imaging.
    • Enabled the use of gray-scale imaging to guide the placement of the ultrasound beam for Doppler signal acquisition.
  • Japanese researchers
    • Developed color-flow mapping techniques.
    • Demonstrated that tissue vascularity increases in the presence of malignant conditions.

Ultrasound: Then and Now

  • Sonography has benefited from computer and technical improvements.
  • New technologies allow ultrasound to diagnose pathology that had traditionally required invasive procedures or the use of potentially nephrotoxic imaging contrast agents, as well as exposing the patient to radiation.
  • Compact and handheld units allow ultrasound to be available in remote places in the world and even in outer space.

The Sonographer

  • Early sonographers were called ultrasound technical specialists.
  • Technician: Someone with 6 weeks to 6 months of education beyond high school.
  • Technologist: Someone who specializes in a technology.
  • Sonographer: Specific to a person who performs medical sonography.

American Registry for Diagnostic Medical Sonography (ARDMS)

  • 1975: ARDMS was tasked with providing valid high-quality certification procedures for medical professionals who performed diagnostic medical sonography.
  • 1983: The practical and oral aspects of the examination were integrated and administered as written questions.
  • 1991: The ARDMS began offering computer-based examinations.
  • 2016: The ARDMS restructured as a council under Inteleos, a new healthcare organization.

Sonologist

  • Ultrasounds may be performed and interpreted by a variety of physicians.
  • Sonologist: A generic term referring to any physician who interprets the ultrasound study.
    • Radiologist: Interprets in the radiology department.
    • Cardiologist: Interprets in the cardiology department.
    • Obstetrician: Interprets in the OB office, MFM, L&D, etc.