SPI URR MOCK EXAM 1 Flashcards
All of the following can be related to color flash artifact except
A. decreased color filter
B. decreased color scale
C. increased color priority
D. decreased color gain
D
Which of the following correctly describes an annular array
A. improved temporal resolution is a primary advantage of annular arrays
B. produces a sector shaped field of view with a flat top
C. offers excellent lateral resolution
D. produces a trapezoid shaped field of view
C, annular arrays improve lateral but degrade temporal, sector is produced
When evaluating a suspected arterial stenosis, a Doppler angle of _____ degrees will produce the most accurate flow velocity
A. 0
B. 30
C. 60
D. 90
A, 0 is the most accurate angle
Which of the following parameters is displayed as the x-axis on a doppler tracing
A. speed
B. time
C. velocity
D. motion
B, x=time y=doppler shift
Which of the following correctly describes dynamic aperture
A. type of transmit focusing
B. will increase the appearance of lobe artifact
C. uses more crystals to receive deep reflections than to shallow reflections
D. also called dynamic frequency tuning
C, type of receive focusing that uses more crystals to receive shallow reflections, reduces lobe artifact
Which of the following bioeffects refers to the formation of microbubbles that burst and cause damage to tissues
A. mechanical index
B. stable cavitation
C. thermal energy
D. transient cavitation
D
If each image requires 50 acoustic pulses and your system displays 30 images per second, what is the pulse rep frequency
A. 60Hz
B. 1500Hz
C. 100Hz
D. 1500ms
B, 30x50=1500
What imaging technique has the worst temporal resolution
A. M-mode
B. 2D imaging
C. color doppler
D. PW doppler
C, m mode has the best temp resolution and color has the worst
Which of the following is true regarding annular arrays and linear arrays
A. annular arrays and linear arrays can be electronically steered
B. annular arrays must be mechanically steered, linear arrays use electronic steering
C. annular arrays have multiple elements, linear arrays have a single element
D. annular arrays can be electronically steered, linear arrays must be mechanically steered
B
What is the primary factor that determines the resistance characeristics of the arterial signal displayed by PW doppler
A. origin of blood
B. part it is supplying
C. vessel course and location
D. branch number
B
A thermocouple device is
A. used only to assess beam intensity at specific locations
B. only used in therapeutic ultrasound
C. used to heat the ultrasound gel for patient comfort
D. used to assess total beam intensity
A, intensity in specific locations, calorimeter is used for total power of the beam
Which of the following is a necessary machine setting when performing a contrast evaluation of the heart
A. mechanical index set to 1.0 or greater
B. harmonic imaging off
C. mechanical index set to 0.3 or lower
D. low PRF color doppler setting
C, higher MI levels will cause premature bursting of bubbles
When frequency increases
A. the wavelength increases because they are indirectly related
B. the wavelength decreases because they are directly related
C. the wavelength decreases because they are indirectly related
D. the wavelength increases because they are directly related
C, frequency and wavelength are inversely related
Activating which of the following ultrasound functions will cause the largest increase in beam intensity
A. M mode
B. color doppler
C. PW doppler
D. B color
C, b mode uses the lowest beam intensity, PW requires highest beam intensity
Which of the following is true regarding continuous wave transducer structure and function
A. CW probes do not require a matching layer
B. CW probes are preferred for detection of low velocity flow
C. CW probes have a single PE element
D. CW probes usually have no backing material
D
When you adjust the doppler PRF, you adjust the ______ control on the system
A. sensitivity
B. velocity scale
C. threshold
D. velocity baseline
B, when you adjust the PRF, you adjust the velocity scale
The best angle of insonation to produce the most accurate doppler shift information is ______ degrees
A. 0
B. 45
C. 60
D. 90
A
Grating lobes degrade
A. lateral resolution
B. axial resolution
C. contrast resolution
D. sound penetration
A
Which of the following will not change with an increase in gain settings
A. reflection amplitude
B. number of echoes displayed
C. brightness of the image
D. signal to noise ratio
D
As beam width increases, how is intensity affected
A. no change except in endocavity probes intensity decreases
B. no change except in endocavity probes intensity increases
C. decreases
D. increases
C
Which of the following patients would need a guardian to sign an informed consent form for a pericardiocentesis
A. blind patient
B. patient with alzeimer’s disease
C. patient that is accompanied by a translator
D. patient with parkinson’s disease
B
Which of the following is necessary for a multihertz transducer
A. broad bandwidth
B. two different sizes of piezoelectric elements
C. two piezoelectric elements
D. narrow bandwidth
A
Increasing overall gain will
A. increase the amplitude of all of the reflectors on the image
B. increase the patient exposure to ultrasound
C. produce a diagnostic image in most cases
D. increase the signal to noise ratio
A
In read magnification, image size and _____ increases. In write magnification, image size and _______ increases
A. relfection amplitude, transmitted amplitude
B. pixel size, number of pixels
C. number of pixels, pixel size
D. frame rate, time of frame production
B, pixel size increases with read and pixel number increases with write
______ can be used to reduce image noise and clutter on the 2D image
A. switching to a curved array transducer
B. spatial compounding
C. adjusting the doppler baseline
D. decreasing transducer frequency
B
_______ is the process that is performed in the beam former where the output voltage is varied to decrease the formation of lobe artifacts
A. autocorrelation
B. spectral analysis
C. quadrature phase detection
D. apodization
D, output voltage is varied with apodization to decrease the formation of lobe artifacts
The doppler shift is 5000Hz. The pulse repetition frequency is 9000Hz. Which of the following is true
A. the peak velocity is qual to 2 m/s
B. the peak pressure gradient is 36 mmHg
C. aliasing will occur
D. range ambiguity will occur
C, nyquist limit=9000/2=4500Hz. the doppler shift is 5000Hz which exceeds the nyquist limit of 4500Hz so aliasing will occur
When arterial stenosis is present, the pressure gradient and ______ will vary in order to maintain a constant _____
A. resistance, velocity
B. resistance, flow rate
C. flow rate, resistance
D. flow rate, velocity
B, pressure gradient and resistance will vary to maintain a constant flow rate
Which of the following console controls can be used to increase the number of scan lines used in a color image
A. persistance
B. rejection
C. output power
D. overall gain
A, increased persistance increase the number of scan lines used to create an image and reduce the frame rate
The main advantage of a curvilinear transducer over a vector transducer is
A. the ability to perform CW doppler with 2D imaging
B. the ability to scan at increased frame rates
C. the wider neaer field
D. the smaller footprint
C
Which of the following correctly describes a difference between read and write magnification
A. read magnification displays a selected portion of the original image from data stored in the system. write mag allows the selection of a region of the image to display and the us system rescans the area to produce a new image
B. write mag displays a selected portion of the original image from data stored in the system. read mag allows the selection of a region of the image to display and the us system rescans the area to produce a new image
C. read mag offers improved spatial and temporal resolution. write mag has no effect on resolution
D. read mag is a pre processing function. write mag is a post processing function
A
Which of the following correctly describes how a linear array transducer produces a trapezoid field of view
A. PE elements are stimulated by times voltage spikes produced in a concave pattern
B. PE elements are stimulated by times voltage spikes produced first on the left and moving to the right side of the array
C. PE elements are stimulated by times voltage spikes produced in a convex pattern
D. PE elements are stimulated by timed voltage spikes produced first on the right and moving to the left side of the array
C, timed voltages produced in a convex shape will create a wider beam, if the voltages are timed to stimulate the elements in a concave pattern a focused beam is produced
You switch from a 5MHz curved probe to a 2.5MHz sector probe to image deeper in the abdomen. How is the attenuation rate affected by the change to the new probe
A. decreases by 25%
B. decreases by 50%
C. doubles
D. increases by 4 times
B, lower frequency probes offer slower attenuation
Which of the following console adjustments will improve the temporal resolution on the image
A. adding another focal zone
B. decreasing imaging depth
C. turning off the zoom function
D. turning on harmonic imaging
B
Tissue doppler imaging uses ______ settings then PW doppler
A. lower frequencies
B. higher filter
C. higher frequencies
D. lower filter
D
The sonographer can improve the axial resolution by
A. increasing the demodulation of the signal
B. adjusting the monitor contrast
C. adjusting the dynamic range
D. using a higher frequency transducer
D, axial resolution is directly related to SPL, pulse length is determined by the frequency of the element
Which of the following will reduce the amount of color doppler information displayed on the image
A. increased sample size
B. increased sensitivity
C. increased packet size
D. increased probe frequency
A, larger sample sizes cause lower frame raets and less accurate color information, the greater # of scan lines the better the color, increasing frequency will improve color
_______ removes low amplitude signals and noise from the image
A. increasing rejection
B. increasing dynamic range
C. increasing compression
D. decreasing the 2D threshold
A, rejection removes low amp noise and signals
If the input power is 2mW and the output power is 200mW, what is the gain
A. 30dB
B. 100dB
C. 20dB
D. 10dB
C
The average attenuation of ultrasound in the soft tissue is
A. 0.5 dB/cm/MHz
B. 0.5 dB/cm
C. 5 dB/cm/MHz
D. 0.5 dB/cm/MHz
A
You are performing a PW doppler exam. Only 2 cardiac cycles are demonstrated on the screen at one time with the current settings. What adjustment can be made to demonstrate 5-6 cardiac cycles on the screen at one time
A. ask the patient to perform the valsalva maneuver
B. increase sweep speed
C. decrease sweep speed
D. increase the frame rate
C, decreasing the sweep speed will demonstrate more doppler changes over a longer amount of time, increasing the sweep speed shows fewer cardiac cycles
The narrowest portion of a beam produced by a focused ultrasound transducer is
A. the first centimeter of the beam that leaves the transducer
B. the focal point
C. the fresnel zone
D. the fraunhofer zone
B
______ artifact is caused by refraction and results in subtle image degradation
A. comet tail
B. misregistration
C. multipath
D. scatter
C
Which of the following system functions allows the linear transducer to offer a trapezoidal field of view
A. mechanical focusing
B. electronic focusing
C. apodization
D. electronic steering
D
Even and odd harmonic frequencies are created by
A. turbulent flow in a blood vessel
B. variable timing of the firing of the piezoelectric elements
C. alternating current to different piezoelectric elements in the transducer array
D. non linear sound wave propagation
D