Part 2 Flashcards
1) Which of the following is described as the ability of an object to resist compression and relates to the hardness of a medium? A) Stiffness B) Density C) Pressure D) Inertia
A
2) An increase in the PRF would lead to A) An increase in the duty factor B) An increase in pulse duration C) An increase in the number of cycles D) A decrease in resolution
A
3) Which of the following would have the highest propagation speed? A) Air B) Bone C) Soft tissue D) Water
B
4) Which of the following would have the lowest propagation speed? A) Water B) Soft tissue C) Bone D) Lung tissue
D
5) As imaging depth increases, the PRF must A) Not change B) Increase C) Decrease D) PRF does not relate to imaging depth
C
6) A pair of waves in phase. What occurs when these waves interfere? A) Reflection B) Constructive interference C) Refraction D) Destructive interference
B
7) The typical range of frequency for diagnostic ultrasound image is: A) 20 to 20000 HZ B) 2 to 15 MHZ C) 10 to 20 MHZ D) 12 to 100 MHZ
B
8) Which of the following is described as the distance over which one cycle occurs? A) Pulse duration B) Duty factor C) Period D) Wavelength
D
9) All of the following are true of stiffness except:
A) It is defined as the ability of an object to resist compression
B) Stiffness and propagation speed are indirectly associated
C) Increasing stiffness increase propagation speed
D) Stiffness may also be referred to as bulk modulus
B
10) Area of high pressure and density is referred to as: A) Compression B) Rarefaction C) Condensation D) Refraction
A
11) Spatial pulse length can be calculated as: A) Number of cycles x frequency B) Period/frequency C) Number of cycles x wavelength D) Number of cycles/wavelength
C
12) As imaging depth increase PRP: A) Remains constant B) Increase C) Decrease D) Doubles
B
13) If PRF increases then the duty factor A) Remains same B) Increase C) Decrease D) Doubles
B
14) The percentage of time that the ultrasound system is producing pulses of ultrasound describes the : A) PRP B) Pulse duration C) Duty factor D) PRF
C
15) Density and propagation speed are: A) Inversely related B) Directly related C) Directly proportional D) Unrelated
A
16) All of the following are true of power except:
A) As amplitude increase power remains same
B) Power is proportional to amplitude squared
C) Intensity is proportional to power
D) Power is measured in milliwatts
A
17) All of the following are true of wavelength except:
A) It is determined by both the medium and sound source
B) It is equal to period divided by the frequency
C) It is inversely related to frequency
D) It is directly related to period
B
18) Which of the following is determined only by the medium? A) Propagation speed B) Frequency C) Period D) Wavelength
A
19) Which of the following is defined as the number of ultrasound pulses emitted in 1 second? A) PRP B) Duty factor C) PRF D) Spatial pulse length
C
20) Which of the following is defined as active time only? A) Duty factor B) PRF C) Period D) Pulse duration
D
21) The maximum value of the density of an acoustic wave is 80 lb/in2 while minimum density is 20 lb/in2. What is amplitude of the wave? A) 20 lb/in2 B) 30 lb/in2 C) 80 lb/in2 D) 60 lb/in2
D
22) When the elasticity of a medium is high, the \_\_\_\_\_\_\_\_\_\_\_\_ is low. A) Compressibility B) transmission C) Reflectivity D) Propagation speed
D
23) What happens to the pulse duration when a sonographer decrease the maximum imaging depth in an Ultrasound? A) Remains same B) Increase C) Decrease D) Cannot be determined
A
24) The duty factor for continuous wave ultrasound is: A) <99% B) 100% C) >20,000 Hz D) 8 Pa
B
25) All of the following relate to the strength of the sound wave except A) Amplitude B) Wavelength C) Intensity D) Power
B
26) What is the change in intensity if the power decreases by half? A) Intensity doubles B) Intensity is halved C) Intensity is one fourth D) Intensity does not change
B
27) What is defined as the beginning of one pulse to the beginning of the next pulse, and therefore includes both the “on” and “off” time? A) Pulse repetition period B) Pulse duration C) Duty factor D) Pulse repetition frequency
A
28) What is essentially equal to the power of a wave divided by the area over which the power is distributed? A) Amplitude B) Power C) Intensity D) Absorption
C
29) What is the change in power if the amplitude triples? A) It doubles B) It triples C) It quadruples D) It increases nine times
D
30) The portion of the sound beam where the molecules are pulled apart describes an area of: A) Compression B) Rarefaction C) Refraction D) Amplitude
B
31) If only the density of a medium is increased, then the: A) Propagation speed will increase B) Propagation speed will decrease C) Propagation speed will stay the same D) None of the above
B
32) Sound is technically a: A) Transverse and longitudinal wave B) Mechanical and transverse wave C) Non mechanical pressure wave D) Mechanical and longitudinal wave
D
33) The maximum value or minimum value of an acoustic variable minus the equilibrium value of that variable describes the: A) Power B) Intensity C) Duty factor D) Amplitude
D
34) Which of the following would be considered ultrasonic? A) 10 Hz B) 12.5 Hz C) 1 MHz D) 200 Hz
C
35) Which of the following is considered the speed of sound in soft tissue? A) 660 m/s B) 330 m/s C) 1480 m/s D) 1540 m/s
D
1) Which of these intensity is smallest? A) SATP B) SPTP C) SATA D) SPPA
C
2) The units of attenuation are \_\_\_\_\_\_\_\_\_\_\_\_\_\_ this is a \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ scale. A) Mm/cm, parametric B) Db/cm, multiplicative C) None, relative D) DB, logarithmic
D
3) Sound wave intensity is attenuated from one fourth of original. How many decibel of attenuation is this? A) 6 DB B) 9 DB C) 10 DB D) 3 DB
A
5) Which of the following tissue has the highest rate of attenuation of an ultrasound wave? A) Liver B) Fat C) Fluid D) Lung and bone E) Muscle
D
6) You are imaging a structure containing two media having same acoustic impedance and normal incidence. What will occur at the boundary of the two structure?
A) All of the sound will be transmitted
B) All of the sound will be reflected
C) Some of the sound will be refracted
D) Some of the sound will be reflected and some of the sound will be transmitted
E) Most of the sound will be absorbed by media boundary
A
7) Snell’s law describes
A) The % of reflection at an interface with normal incidence and different densities
B) The angle of transmission at an interface between media having different speed
C) The amount of attenuation of sound in tissue with depth
D) The amount of backscatter from a diffuse reflector
B
8) What occurs when you image a structure with oblique incidence?
A) A very strong reflection will occur since this is the optimal angle for imaging
B) All of sound will be reflected due to poor scanning angle
C) All of the sound will be transmitted due to poor scanning angle
D) The angle of reflection will be oriented away from the transducer, resulting in decreased visualization of the structure
E) The amount of scattering will be reduced with a scanning angle of 45°, resulting in a cleaner image with reduced artefactual echoes.
D
9) If an angle of incidence is 50°, what is the angle of transmission at the interface if medium 1 has a propagation speed of 1560 m/s and medium 2 has a propagation speed of 1900 m/s? A) <50 degrees B) >50 degrees C) 50 degrees D) Cannot tell the angle of transmission
B
10) Which of the following statement regarding the effect of frequency on Rayleigh scattering is true?
A) The amount of scattering is not affected by scattering
B) Scattering intensity doubles if frequency doubles
C) Doubling the frequency resulting in halving the scattering intensity
D) Doubling the frequency resulting in quartering the scattering intensity
E) Scattering intensity is proportional to frequency raised to the fourth power
E
11) What is relationship of frequency to absorption?
A) If frequency is halved, absorption is doubled
B) If frequency is doubled, absorption is doubled
C) If frequency is doubled, absorption is halved
D) If frequency is halved, absorption is quartered
E) The rate of sound absorption is not frequency dependent
B
12) The maximum imaging depth during an ultrasound exam is 5 cm. The sonographer adjust the imaging depth to 10 cm. What happens to go return time? A) It is unchanged B) It is halved C) It is doubled D) It is 20 times longer
C
13) A sound wave is created by transducer, reflects off an object, and return to the transducer. The go return time is 39 micro secs. What is the total distance that the pulse travelled? A) 3 cm B) 6 cm C) 2 cm D) 9 cm
B
14) A sound beam travels 9 cm in soft tissue. The attenuation co efficient is 3 DB/cm. What is the total attenuation that the sound beam experienced? A) 9 DB B) 3 DB C) 27 DB D) 18 DB
C
16) A sound beam with an Intensity of 50 Watts/cm2 strikes a boundary and 70 % of the wave’s intensity is reflected. How much is transmitted? A) 25 Watts/cm2 B) 30% C) 50 Watts/cm2 D) 100 %
B
17) While performing a sonographic exam, you encounter following interfaces. Which will produce the weakest reflected signal? A) Organ parenchyma/fluid B) Organ parenchyma/air C) Organ parenchyma/ Organ parenchyma D) Organ parenchyma/bone E) Organ parenchyma/ligament
C
18) What sound –tissue interaction is necessary to form an ultrasound image? A) Rarefaction B) Refraction C) Diffraction D) Destructive interference E) Reflection
E
19) \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ is a redirection of ultrasound in many direction as a result of a rough boundary between two media. A) Refraction B) Scattering C) Reflection D) Rayleigh scattering
B
20) Which of the following terms does not belongs with others? A) Orthogonal B) Oblique C) Normal D) Perpendicular
B
21) Which of the following is most relevant intensity in the study of Bioeffects/ A) SPTP B) SPTA C) SATA D) SATP
B
22) Which of the following is the part of the transducer that stops the ringing of the element? A) Matching layer B) case C) Damping material D) Insulator
C
23) Which of the following is the range of frequencies present within the beam? A) Quality factor B) Bandwidth C) Array D) Resonant frequency
B
24) What does heat sterilization do to an ultrasound transducer?
A) Gives it a better axial resolution
B) Improves lateral resolution of the transducer
C) Kills the bacteria and viruses
D) Kills pathogen and destroy transducer
D
25) All of the following correctly describes an imaging transducer except A) High sensitivity B) Low Q factor C) Wide bandwidth D) Damped
A
26) A pulsed wave transducer has a resonant frequency of 5 MHZ. The lowest frequency in the pulse is 2 MHZ and the Highest is 8 MHZ. What is Q factor? A) 0.8 B) 3 MHZ C) 5 MHZ D) 1.9 E) 2 MHZ
B
27) In an imaging transducer what is purpose of attaching the backing material to PZT? A) Increase bandwidth B) Decrease Q factor C) Improve image Quality D) Decrease transducer sensitivity
C
28) Which of the following lists order of impedance from lowest to highest? A) Skin, gel, matching layer, PZT B) Gel, matching layer, skin, PZT C) PZT, matching layer, gel, Skin D) Matching layer, Gel, Skin, PZT
A
29) The backing material decrease A) Bandwidth B) Quality factor C) Size of case D) PRP
B
30) What is thickness of a matching layer of a 3 MHZ pulsed wave transducer?
A) 1.54 mm
B) 0.77 mm
C) Half the wavelength of the sound wave in the PZT
D) One quarter the wavelength of sound in the matching layer
D
31) What helps to determine the frequency of the sound produced by the transducer of a continuous wave ultrasound system? A) PZT diameter B) PZT crystal thickness C) Damping material density D) Ultrasound system electronics
D
32) You are asked to fabricate a pulsed ultrasound transducer with the highest possible frequency. Which piezoelectric crystal would you select
A) 8 mm thick, 4 cm diameter, 4 mm/microsec propagation speed
B) 6 mm thick, 2 cm diameter, 6 mm/microsec propagation speed
C) 4 mm thick, 9 cm diameter, 5 mm/microsec propagation speed
D) 3 mm thick, 6 cm diameter, 6 mm/microsec propagation speed
D
33.The impedance of a transducer’s active elements 1,900,000 rayls and the impedance is 1400000. What is an acceptable impedance for the matching layer? A. 1,407,00 rayls B. 2,400,000 rayls C. 1,200,000 rayls D. 1,726,444 rayls E. 1,900,000 rayls
D
34.An ultrasound system is set at 0 DB and is trsansmitting a full intensity. What is the output power when the system is transmitting at 50 % of full intensity? A) – 3DB B) -10DB C) 3 DB D) 10 DB E) -50 DB
A
.Which of the following describes the situation where the minimum amount of attenuation will occur? A) 4 cm depth and 6 MHZ frequency B) 20 cm depth and 3 MHZ frequency C) 12 cm depth and 7.5 MHZ frequency D) 4 cm depth and 9 MHZ frequency E) 4 cm depth and 7.5 MHZ frequency
A
1. Which of the following transducers has the worst depth resolution? A) 3 MHz & 5 cycles/pulse B) 2 MHZ & 5 cycles/pulse C) 3 MHz & 2 cycles/pulse D) 2 MHz & 2 cycles/pulse
B
- What will lower the numerical value of an ultrasound system’s lateral resolution?
A) Decrease the # of cycles in the pulse
B) Increase the effective damping material
C) Increase the PRP
D) Use of an acoustic lens
D
- Which of the following techniques is considered external focusing?
A) Lens
B) Curved crystal
C) Electronic
D) Phased array
A
- Which of the following transducers has the best lateral resolution deep in the far field?
A) 4 MHz, 4 mm diameter of the PZT
B) 6 MHz, 4 mm diameter of the PZT
C) 4 MHz, 6 mm diameter of the PZT
D) 6 MHz, 6 mm diameter of the PZT
D
