|
|
 |
 |
 |
|
|
|||
|
||||
|
||||
Re: [soundadvice] vector versus curvi-linearFrom: DuBose, Terry (DuboseTerryJ@exchange.uams.edu)Wed Dec 10 13:39:21 1997
Jeff, Ellison, I didn't have time to respond when this message first came across, and I do not directly work with the New Sequoias, so I didn't respond. However, my students do rotate through 2 clinics where they have new Sequoias. The new machines have something called "harmonic mode" that seems to clear up the image in the far field in large people. Also, increases contrast. I talked to the ACUSON rep. And he gave me some literature and tried to explain Harmonics. Apparently every true echo includes a sub-harmonic that is twice the frequency of the primary echo. So when you go into harmonic mode, the "real" echo is ignored and the machine only looks for the harmonic echoes. The end result seems to be a reduction of the "speckle" that is so troublesome in large patients. At least that is the way I understand it. I do not know if there are certain transducers that this is most effective with, but I suspect that it will be most effective at lower frequencies. May be Jim Zabzebski can make this clearer. Peace, Terry J. DuBose, M.S., RDMS; Assistant Professor -----Original Message----- From: emdee1@juno.com [SMTP:emdee1@juno.com] Jeff, I don't use a sequoia but a regular xp/10. In general the curvi- linear probe will have the best resolution because each beam line produced is perpendicular to the elements producing the sound line. In a vector probe the pulsing sequence is a phased arrangement whereby all the elements are pulsed simultaneously for each beam line. These beam lines are steered at an angle that is not perpendicular to the elements. Unless the sequoia technology has changed this the above is generally true. You can prove this by scanning the same subject using both probes and visually comparing. Ellison Marshall, BSRT, RDMS Faculty, Austin Community College e-mail: Emdee1@Juno.com
|
|
Return to
|
Mail a New Message to the Forum: ultrasound@obgyn.net Forum Administrator: terry.dubose@obgyn.net Report Technical Problems: webmaster@obgyn.net Last Updated: Mon Nov 2 05:38:25 2009 |
The American Medical Association is no longer designating CME hours for AMA Category II CME credit. However, physicians themselves may self designate learning activities as Category II CME credit hours if they feel it is of sufficient educational merit and meets the formal definitions of continuing medical education. OBGYN.net believes these interaction in this forum meets these criteria. For further information see the AMA web site.