ARDMS SPI Exam Already Graded A+

ARDMS SPI Exam Already Graded A+ Which gain will increase the risk of bioeffects? a. transmit b. receive c. gain d. overall gain Ans- a. transmit Which of the following is considered the memory of an ultrasound instrument? a. pulser b. transducer c. receiver d. beam former e. digital scan converter f. display monitor Ans- e. digital scan converter Spectral broadening suggest: a. laminar flow b. turbulent flow c. flow away from the transducer d. flow towards the transducer Ans- b. turbulent flow With pulse wave Doppler axial resolution: Ans- degrades What color is usually use in color flow Doppler variance map to indicate turbulent flow? Ans- green Doppler high pass filter eliminates: Ans- high amplitude signals; low velocity flow The Doppler wall filter is considered a: Ans- high pass filter The Nyquist Limit is equal to: a. propagation speed x frequency b. propagation speed/ wavelength c. PRF/2 d. 4xV^2 Ans- c. PRF/2 Multiple echoes, equally spaced originating from a gas bubble is called: a. comet tail b. ring down c. slice thickness artifact d. multipath Ans- b. ring down An increase in red blood cell velocity will_____ the Doppler Shift: a. increase b. decrease c. not change d. cannot be predicted Ans- a. increase The primary advantage of CW Doppler is: a. range resolution b. range discrimination c. range ambiguity d. range gating e. absence of sampling rate Ans- e. absence of sampling rate The range for ultrasound begins: a. 20 Hz b. 20,000 Hz c. 2 MHz d. 15 MHz Ans- b. 20,000 Hz (useful frequency range for clinical imaging is 2MHz-10MHz) Which instrument control affects the amplitude (dB) of the outgoing signal: a. gain b. receiver gain c. TGC d. transmit gain e. overall gain Ans- d. transmit gain; amplitude can be affected by the sonographer Which of the following is used to convert Doppler shift information into color: a. high PRF b. fast Fourier transform c. autocorrelation d. time interval histogram Ans- c. autocorrelation b is incorrect because fast Fourier transform is the method used to process conventional Doppler shift information but is too slow a method for color Doppler Pulse repetition frequency Ans- Number of pulses that an ultrasound system transmits into the body each second. Hz. Typically 4-15 KHz. PRF and depth of a view are inversely related: When system is imaging deeper, the pulse repetition frequency is lower. Also the number of pulses created each second The best way to increase the near field length of an ultrasound beam is to: Ans- increase transducer diameter The range of frequencies produced by a damped PZT element is called: a. fundamental frequencies b. Q Factor c. near field d. bandwith Ans- d. bandwidth The percentage of time that the ultrasound instrument is emitting ultrasound is called: a. PRF b. pulse duration c. pulse repetition period d. duty factor Ans- d. duty factor; the maximum value is 1, the minimum is 0 The unit of duty factor is: a. Hz b. mm c. ms d. unitless Ans- d. unitless Quality Factor= Fundamental frequency/ bandwidth Ans- This allows doses of different types of radiation to be compared for their biological effects. Clinical imaging transducers are: Ans- wide bandwidth; low q factor Power/area= Ans- Intensity Increasing wavelength will ___________ frequency. a. increase b. decrease c. not change d. cannot be predicted. Ans- b. decrease All of the following directly affect frame rate except: a. depth of penetration b. field of view c. number of focuses d. line density e. beam width Ans- e. beam width A reflection will occur at the boundary of two media if the acoustic impedences of the two media are: a. equal b. different c. unchanged d. cannot be predicted Ans- b. different A mechanical transducer utilizes: a. transmit focus b. receive focus c. fixed focus d. dynamic aperture focusing Ans- c. fixed focus; sonographer cannot determine the location of # of foci. mechanical transducer uses cross sectional imaging, rotating wheel, wobbler, oscillating mirror The transducer frequency is primarily determined by the transducer element: a. diameter b. thickness c. propagation speed d. type Ans- b. thickness A strongly focused transducer implies a: a. short focal length; decreased beam divergence b. medium focal length; increased beam divergence c. long focal length; no beam divergenc d. short focal length; increased beam divergence Ans- d. short focal length; increased beam divergence B-mode displays reflector: a. amplitude and distance b. amplitude and velocity c. power and direction d. depth and speed Ans- a. amplitude and distance An increase in the number of pixels on the display will improve: Ans- detail resolution Propagation speed is determined by: a. frequency b. harmonics c. bandwidth d. bulk modulus Ans- d. bulk modulus Increasing transmit gain increases everything except: Ans- frequency The correct depth placement of reflectors depends primarily upon: a. frequency b. period c. power d. propagation speed Ans- d. propagation speed Which of the following will increase the color flow jet area displayed? a. increase color gain b. increase velocity scale c. increase frequency Ans- a. increase color gain Increasing propagation speed: Ans- air, soft tissue, bone The most common type of transducer used