Ultrasounds Flashcards
is a mechanical wave propagated through a medium at a high frequency to produce images of structures within the human body
Ultrasound
Is a phenomenon where distortion of a crystal causes an electrical change
Piezoelectric effect
How are ultrasound waves generated?
By the application of electrical current to piezoelectric crystals in the transducer
Higher frequency probes are used to give high resolution images of?
Shallow structures
The lower frequency probes are used for?
Deep abdominal imaging
Black images on an ultrasound indicate
Air and fluid
What is always a shade of grey on ultrasounds?
Tissue
The denser the tissue the?
The brighter white it will appear
Is an operating mode in which a two dimensional image is generated that portrays moving reflectors in color simultaneously with images
Color flow Doppler
Term: regulates the amplification ( brightness) of returning echoes to compensate for loss of transmitted sound caused by absorption and reflection
Gain
A relative term that refers to the echoes returned from a structure. And referred to a lesion or tumor which produces a stronger echo than the surrounding structures or tissues
Hyperechoic
Refers to structures that contain fewer or weaker echoes than surrounding tissues
Hypoechoic
Ability to distinguish between two adjacent structures
Resolution
Color doppler: assign colors to represent the flow away or towards the probe. Often used to determine blood flow. What colors are shown when going towards or away from the probe? BART
Blue ( away)
Red ( towards)
Is an electromechanical device that is part of the ultrasound system. It touchs the patient and converts electrical energy into mechanical energy
Transducer
What are the three main types of probes
Curvilinear
Linear
Phased array probe
Probe for abdominal and obstetrics
Curvilinear
Probe used for soft tissue and small parts imaging
Linear probes
Use computer control to “ bend” the US beam from flat, small footprint to a wider pie-shaped wedge distally
Phased array probes
What is the purpose of conducting gel?
To eliminate air between probe and skin
What are the ultrasound views
Sub-xyphoid and left parasternal
In the sub-xyphoid view the displayed screen should show the following?
Portion of the liver at the top In order: R ventricle Intraventricular Septum Left ventricle
Placement for the left parasternal view
Left of sternum
5th intercostal space
Probe marker to the patient’s right
What should visualized in the left parasternal view
Pericardium
Right ventricle
Interventricular septum
Left ventricle
