Ultrasound Flashcards
What color do solid structures show up as on ultrasound?
white
what is m-mode on ultrasound?
moving mode
What shows up as red on Doplar mode on the utrasound?
things moving toward you
blue on the doplar mode indicates what on ultrasound?
things moving away
T or F: using zoom preserves resolution?
FALSE, the depth knob preserves resolution
How far should the image be from the bottom of the ultrasound screen?
2 fingerwidths
What does gain control in ultrasound?
Controls the amount of signal returning to the machine, makes images brighter
What is time gain compensation?
allows for differential amplification of signals returning from deeper structures
*allows you to get a symmetric image
What is the near field?
top skinny part of the ultrasound - contains objects that are superficial to the probe
What is the focal zone?
it’s located between the near and far field
What helps to fine tune axial resolution?
frequency key - higher frequency is better
* axial resolution is up and down from near field to far field
What helps fine tune lateral resolution?
focal zone key
* lateral resolution is side to side res. and decreases with depth
What color and anechoic, hyperechoic and isoechoic objects respectively?
black, white, same as surrounding tissue
When would you use a linear transducer?
When depth isn’t an issue (aka a high frequency transducer)
When do you use a curved-linear transducer?
When you need greater penetration and are less worried about anatomic detail
