Medical Ultrasound Imaging Josh Nolting Graduate Student University of Colorado, APPM Dept.

Presentation Overview  General ultrasound method  Comparison between ultrasound and x-ray  History  Various uses  Physics of the method  Current state  Continuing technology  Conclusion

General method  Place small transducer against the skin  Emits high frequency sound waves  Detects bounce back waves  Different tissues reflect different waves  Reconstruction software  Viewing structure on a screen

Diagnostic UltrasoundX-rays (radiology) wave typelongitudinal mechanical waves electromagnetic waves transmission requirements elastic mediumNo medium generationstressing the mediumaccelerating electric charges velocity depends on the medium through which it propagates It is relatively constant: 299, m/s similar wavesseismic, acousticradio, light

History  Discovery  High frequency (“ultrasound”)  Lazzaro Spallanzini, 1794  Bats navigation  Francis Galton  Galton whistle (above audible frequency)  Gabriel Lippman, 1881  Reciprocal behavior of achieving a mechanical stress in response to a voltage difference was mathematically deduced.  Generation and reception of ‘ultrasound’

History  First use of diagnostic ultrasound  Dr. Karl Dussik, 1942  Locate brain tumors  Two devices  Emitter and reciever

Physics of the Method  Longitudinal mechanical waves  Needs elastic medium  Transducer needs to be in contact with skin  Component resolution  3 MHZ ->1.1 mm  10 MHZ ->.3 mm  Wave velocity  Fat -> 1450 m/s  Muscle ->1580 m/s

Various Uses  View soft tissue  Heart  Pelvis and reproductive organs  Kidneys, liver, pancreas, gall bladder  Eye  Thyroid  Blood vessels  Fetus

Current State  3D/4D images can be attained  Used in conjunction with 2D

4D yawn  4D Yawn 4D Yawn

Current State  Telesonography  Remote ultrasound diagnosis  Mainly used as a “store and forward technology”

Continuing Technology  Color Imaging  Quantum computing  Detection of more tissues  Better transducers (ie. Higher resolution)  More readings  Better breast cancer detection  Can decypher between a malignant mass and a benign cyst.  Painless and safe compared to mammography

Color Imaging

Conclusion  Ultrasound is an important medical imaging mechanism  Non-invasive  Powerful  Cheap

References  “Medical Procedures”,Imaginis Corporation. Updated 10 November This document is  “High Definition Three-Dimensional Ultrasound”, University of Cambridge. This document is  “History of Ultrasound in Obstetrics and Gynecology”, Woo, Joseph. This document is  “3D/4D Ultrasound: State-of-the-Art Technology”, Greater Pittsburgh Ob/Gyn &Mercylink. This document is  “Telemedicine”, Dr. G Diaz. This document is

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