Prototype ultrasound instrument for brain scan
date: label: date made
content: 1949
name: label: Associated Name
content: Reid, John M.
label: Associated Name
content: Neal, Donald
label: Associated Name
content: University of Minnesota
label: Associated Name
content: National Cancer Institute
label: Associated Name
content: National Institutes of Health
label: maker
content: Wild, John J.
notes: label: Description
content: This is a sound head created by John J. Wild in 1949. It is a brass capsule constructed by Wild to house a piezoelectric quartz crystal, or transducer. The crystal is still within the sound head. Wild called this an "echoscope." Wild created a cylindrical tube to house the crystal so as to better direct sound waves towards the tissue being imaged. The device would be used vertically. The cylindrical design also allowed the sound head to be filled with water and covered with a rubber membrane (condom) which essentially makes the transducer self-contained. Previously, the sound heads were used in large water tanks. This sound head unscrews into three parts. One part cradles the crystal while the second part, when screwed into the first part, holds the crystal firmly in place. The last, longer part screws together to form the complete brass tube. The open end is meant to be placed towards the tissue being imaged. The opposite end is meant to be connected to the brass tube also collected here.
label: Description
content: The brass tube was meant to be connected to the sound head and then inserted into a hollow glass tube. When connected to a power source and display unit, the device could create A-mode ultrasound waves. Wild used this technique to image a living human brain twice, as well as postmortem brains. He was able to demonstrate that tissue that contained tumors and tissue without tumors displayed different types of ultrasound waves. Wild went on to develop more sophisticated instruments for ultrasound imaging in the 1950s.
label: Description
content: The basic ultrasound machine is made up of a transducer, amplifier, and display unit. The transducer is placed close to the tissue being imaged and electrical signals cause the transducer inside to produce mechanical sound waves. The transducer sends sound waves into the tissue which then bounce back as echoes. Each echo is received as sound waves and translated back to an electrical signal by the transducer. The electric signal is amplified many times which allows it to be "read" by the display unit, creating the image of dots on the screen. Each dot corresponds to the time (depth,) amplitude (strength,) and, later, location of the obstruction that sent that particular echo back.
label: Location
content: Currently not on view
place: label: place made
content: United States: Minnesota, Minneapolis
label: place made
content: United States: Minnesota, Minneapolis
label: Associated Place
content: United States: Minnesota, Minneapolis, Wold-Chamberlain Air Base/Station
label: Associated Place
content: United States: Minnesota, Minneapolis
topic: label: Subject
content: Ultrasound
label: Subject
content: Radar
label: Subject
content: Medicine
label: Subject
content: Cancer
label: Subject
content: Diagnostic Equipment
label: Subject
content: Imaging
setName: label: See more items in
content: Medicine and Science: Medicine
creditLine: label: Credit Line
content: Gift of Ellen L. C. Wild and Valerie C. Wild
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 2015.0300.03
label: accession number
content: 2015.0300
label: catalog number
content: 2015.0300.03
objectType: label: Object Name
content: sound head with prototype ultrasound instrument
physicalDescription: label: Physical Description
content: brass (overall - sound head material)
label: Physical Description
content: brass (overall - tube material)
label: Measurements
content: overall - sound head: 6 cm; 2 3/8 in
label: Measurements
content: wide end - sound head: 2 cm; 25/32 in
label: Measurements
content: small end - sound head: 1.4 cm; 9/16 in
label: Measurements
content: overall - tube: 35 cm x 1.7 cm; 13 25/32 in x 21/32 in