UltraSound - Technology Information PortalThursday, 21 February 2019
Info
  Sheets



Out-
      side
 




 
 'Matrix' 
SEARCH FOR   
 
  12345ABCDEFGHIJKLMNOPQRSTUVWZ
Result : Searchterm 'Matrix' found in 2 terms [] and 4 definitions [])
1 - 5 (of 6)     next
Result Pages : [1]  [2]
Searchterm 'Matrix' was also found in the following services: 
spacer
News  (5)  Resources  (1)  
 
MatrixMRI Resource Directory:<br> - UltraSound Physics -
 
A matrix is a set of numbers arranged in a rectangular array. The array of numbers is divided in rows and columns. The matrix size determines the scan resolution.
spacer
• Related Searches:
    • Cross-section Scattering
    • Osmole
    • Ultrasound Physics
    • Directivity Index
    • Target Strength

 Further Reading:
  Basics:
Matrix (mathematics)Open this link in a new window
   by en.wikipedia.org    
  News & More:
Transmission Line Matrix (TLM) modelling of medical ultrasound(.pdf)Open this link in a new window
   by www.era.lib.ed.ac.uk    
Searchterm 'Matrix' was also found in the following services: 
spacer
Radiology  (12) Open this link in a new windowMRI  (81) Open this link in a new windowMarket  (1) Open this link in a new window
Matrix SizeMRI Resource Directory:<br> - Image Quality -
 
The matrix size is the number of data points collected in one, two or three directions. Normally used for the 2D in plane sampling. The display matrix may be different from the acquisition matrix, although the latter determines the resolution.
spacer

 Further Reading:
  Basics:
Ultrasound and k-space K-space transforms of elementary geometriesOpen this link in a new window
   by dukemil.egr.duke.edu    
US Resources  
Modes - Renal - Calculation - Quality Advice - Fetal - Vascular
 
History of UltrasoundMRI Resource Directory:<br> - History of UltraSound -
 
point In 1880 the Curie brothers discovered the piezoelectric effect in quartz. Converse piezoelectricity was mathematically deduced from fundamental thermodynamic principles by Lippmann in 1881.
point In 1917, Paul Langevin (France) and his coworkers developed an underwater sonar system (called hydrophone) that uses the piezoelectric effect to detect submarines through echo location.
point In 1935, the first RADAR system was produced by the British physicist Robert Watson-Wat. Also about 1935, developments began with the objective to use ultrasonic power therapeutically, utilizing its heating and disruptive effects on living tissues. In 1936, Siemens markets the first ultrasonic therapeutic machine, the Sonostat.
point Shortly after the World War II, researchers began to explore medical diagnostic capabilities of ultrasound. Karl Theo Dussik (Austria) attempted to locate the cerebral ventricles by measuring the transmission of ultrasound beam through the skull. Other researchers try to use ultrasound to detect gallstones, breast masses, and tumors. These first investigations were performed with A-mode.
point Shortly after the World War II, researchers in Europe, the United States and Japan began to explore medical diagnostic capabilities of ultrasound. Karl Theo Dussik (Austria) attempted to locate the cerebral ventricles by measuring the transmission of ultrasound beam through the skull. Other researchers, e.g. George Ludwig (United States) tried to use ultrasound to detect gallstones, breast masses, and tumors. This first experimentally investigations were performed with A-mode. Ultrasound pioneers contributed innovations and important discoveries, for example the velocity of sound transmission in animal soft tissues with a mean value of 1540 m/sec (still in use today), and determined values of the optimal scanning frequency of the ultrasound transducer.
point In the early 50`s the first B-mode images were obtained. Images were static, without gray-scale information in simple black and white and compound technique. Carl Hellmuth Hertz and Inge Edler (Sweden) made in 1953 the first scan of heart activity. Ian Donald and Colleagues (Scotland) were specialized on obstetric and gynecologic ultrasound research. By continuous development it was possible to study pregnancy and diagnose possible complications.
point After about 1960 two-dimensional compound procedures were developed. The applications in obstetric and gynecologic ultrasound boomed worldwide from the mid 60’s with both, A-scan and B-scan equipment. In the late 60’s B-mode ultrasonography replaced A-mode in wide parts.
point In the 70’s gray scale imaging became available and with progress of computer technique ultrasonic imaging gets better and faster.
point After continuous work, in the 80’s fast realtime B-mode gray-scale imaging was developed. Electronic focusing and duplex flow measurements became popular. A wider range of applications were possible.
point In the 90’s, high resolution scanners with digital beamforming, high transducer frequencies, multi-channel focus and broad-band transducer technology became state of the art. Optimized tissue contrast and improved diagnostic accuracy lead to an important role in breast imaging and cancer detection. Color Doppler and Duplex became available and sensitivity for low flow was continuously improved.
point Actually, machines with advanced ultrasound system performance are equipped with realtime compound imaging, tissue harmonic imaging, contrast harmonic imaging, vascular assessment, matrix array transducers, pulse inversion imaging, 3D and 4D ultrasound with panoramic view.
read more

Radiology-tip.comDiagnostic Imaging
spacer
Radiology-tip.comMRI History
spacer

 Further Reading:
  News & More:
Physics Tutorial: Ultrasound PhysicsOpen this link in a new window
   by www.physics247.com    
A-Mode Area RatioOpen this link in a new window
   by www.wildultrasound.com    
Searchterm 'Matrix' was also found in the following services: 
spacer
News  (5)  Resources  (1)  
 
Linear Array TransducerInfoSheet: Probes/Transducers
Intro,
Probes, 
TransducersMRI Resource Directory:<br> - Probes Transducers -
 
Linear array transducer elements are rectangular and arranged in a line. Linear array probes are described by the radius of width in mm. A linear array transducer can have up to 512 elements spaced over 75-120 mm. The beam produced by such a narrow element will diverge rapidly after the wave travels only a few millimeters. The smaller the face of the transducer, the more divergent is the beam. This would result in poor lateral resolution due to beam divergence and low sensitivity due to the small element size.
In order to overcome this, adjacent elements are pulsed simultaneously (typically 8 to 16; or more in wide-aperture designs). In a subgroup of x elements, the inner elements pulse delayed with respect to the outer elements. The interference of the x small divergent wavelets produces a focused beam. The delay time determines the depth of focus for the transmitted beam and can be changed during scanning.
Linear arrays are usually cheaper than sector scanners but have greater skin contact and therefore make it difficult to reach organs between ribs such as the heart. One-dimensional linear array transducers may have dynamic, electronic focusing providing a narrow ultrasound beam in the image plane. In the z-plane (elevation plane - perpendicular to the image plane) focusing may be provided by an acoustic lens with a fixed focal zone.
Rectangular or matrix transducers with unequal rows of transducer elements are two-dimensional (2D), but they are termed 1.5D, because the number of rows is much less than the number of columns. These transducers provide dynamic, electronic focusing even in the z-plane.
See also Rectangular Array Transducer.
spacer

 Further Reading:
  Basics:
Ultrasound Physics Main differences between Ultrasound and X-rays, Velocity of sound in some Biological MaterialsOpen this link in a new window
   by www.drgdiaz.com    
  News & More:
Ultrasonic Testing Using Phased ArraysOpen this link in a new window
   by www.ndt.net    
Searchterm 'Matrix' was also found in the following services: 
spacer
Radiology  (12) Open this link in a new windowMRI  (81) Open this link in a new windowMarket  (1) Open this link in a new window
Rectangular Array TransducerInfoSheet: Probes/Transducers
Intro,
Probes, 
TransducersMRI Resource Directory:<br> - Probes Transducers -
 
The elements of a rectangular array transducer (also called matrix transducer) are arranged in a rectangular pattern. Rectangular arrays with unequal rows (e.g. 3, 5, 7) of transducer elements are in real 2D (two-dimensional), but they are termed 1.5D, because the number of rows is much less than the number of columns. Their main advantage is electronic focusing even in the elevation plane (z-plane).
The transducers that are termed 2D have an equal number of rows and columns. 2D transducers have the potential to provide real-time 3D ultrasound imaging without moving the transducer.
Active matrix array transducers have several elements in the short axis and in addition multiple elements along the long axis. This allows electronic focusing in both axes, resulting in a narrower elevation axis beam width in the near field and far field.
spacer

US Resources  
Abdominal - Intravascular - Image Quality - Ultrasound Gel - Probes Transducers - Examinations
 
Related Searches:
 • Sonar
 • Blanking Distance
 • Ampere
 • Directivity Index
 • Specular Echo
SEARCH FOR   
 
  12345ABCDEFGHIJKLMNOPQRSTUVWZ
     1 - 5 (of 6)     next
Result Pages : [1]  [2]
 Random Page
 
Share This Page
FacebookTwitterLinkedIn

US-TIP    
Community   
User
Pass
Forgot your UserID/Password ?  


Look
      Ups



UltraSound - Technology Information Portal
Member of SoftWays' Medical Imaging Group - MR-TIP • Radiology-TIP • US-TIP • 
Copyright © 2006 - 2018 SoftWays. All rights reserved.
Terms of Use | Privacy Policy | Advertising
 [last update: 2015-03-04 09:17:02]