HIGH YIELD POINT FOR RADIOLOGY 2015

HIGH YIELD POINT FOR RADIOLOGY 2015


http://www.doctorsquiz.com important topics for DNB-CET, AIPGMEE, FMGE, DNB-PDCET, UPSC-CMS online medical examination .



THE  modes of ultrasound(USG) are used in medical imaging :-


· A-mode: A-mode is the simplest type of ultrasound. A single transducer scans a line through the body with the echoes plotted on screen as a function of depth. Therapeutic ultrasound aimed at a specific tumor or calculus is also A-mode, to allow for pinpoint accurate focus of the destructive wave energy. Used only in eye scan.

· B-mode: Most commonly used. In B-mode ultrasound, a linear array of transducers

simultaneously scans a plane through the body that can be viewed as a two-dimensional image on screen.

· M-mode: M stands for motion. In m-mode a rapid sequence of B-mode scans whose

images follow each other in sequence on screen enables doctors to see and measure range of motion, as the organ boundaries that produce reflections move relative to the probe.
· Doppler mode: This mode makes use of the Doppler effect in measuring and visualizing

blood flow-

· Color doppler: Velocity information is presented as a color coded overlay on top of a B-mode image

· Continuous doppler: Doppler information is sampled along a line through the

body, and all velocities detected at each time point is presented (on a time line)

· Pulsed wave (PW) doppler: Doppler information is sampled from only a small sample volume (defined in 2D image), and presented on a timeline

· Duplex: a common name for the simultaneous presentation of 2D and (usually)

PW doppler information. (Using modern ultrasound machines color doppler is almost always also used, hence the alternative name Triplex.)




READ MORE