Kristy,
Use a zero degree angle if the vessel is vertical on the screen. Remember why we use a 60 degree or less angle, it's to reduce the amount of velocity measurement error, which exponentially increases if your angle is greater than 60 degrees. If it's 60degrees or less, an overestimated velocity is still within 5 percent of the true velocity. I personally believe some are stringent on the 60degree angle because it's easily reproducible when repeated by any tech, and most ultrasound research (especially carotid studies) use a 60degree angle for easy follow up and to reduce measurement error. In general, I find decreasing the angle typically decreases your velocities and does not overestimate them.
Matt
-----Original Message-----
From: UVM Flownet [mailto:[log in to unmask]] On Behalf Of Kristy Peeler
Sent: Monday, January 26, 2009 13:58
To: [log in to unmask]
Subject: Re: angles
Please explain how to get a 60 degree angle on a vessel that is diving
straight down, i.e.: distal ICA.
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