SPI Exam

biologic effects have not been documented below what intenity? (SPTA) A. 100 W/cm B. 100 mW/ m^2 C. 100 mW/cm^2 D. 100 mW/cm ^3

C. 100 mW/cm^2

Which of the following frequencies is in the ultrasound range? A. 15 Hz B. 15 KHz C. 15MHz D. 17000 Hz

C. 15 MHz

for oblique incidence and a medium 2 speed that is equal to twice the speed of medium 1, the transmission angle will be about ___ times the incidence angle A. 0.5 B. 17 C.2 D. 4

C. 2

Diagnostic ultrasound frequecny range is ____ A. 2 to 10 mHz B. 2 to 10 kHz C. 2-10 MHz D. 5-15 KHz

C. 2-10 MHz

T or F. doppler shifts always occur if the sound source and reciver are in motion

F. no doppler shift if they are moving together

what is the wavelength of 1 MHz ultraouns in tissue with a propagation speed of 1540 m/s? A. 1 x 10^6m B. 1.54 mm C.1540 m D. 1.54 cm

1.54 mm

an ultrasound system is set at 0 dB and is transmitting at full intensity. what is the output power when the system is transmitting at 50% of full intensity? A. -3 dB B. -50 dB C. 10 dB D. 3 dB E. -10 dB

A. -3 dB

what is the approximate attenuation coefficient of 1 MHz US in soft tissue? A. 0.5 dB/cm B. 1 cm C. 3 dB/cm D. 1 dB

A. 0.5 dB/cm

transducer operating properly in pulse-echoh imaging system have a uality factor of approximately A. 1 to 3 B. 7 to 10 C. 25 to 50 D. 100

A. 1 to 3

if pulse duration is 1 us and the pulse repeition period is 100 us, duty factor is A. 1% B.10% C.50% D.100%

A. 1%

The averae propagation speed in soft tissue is A. 1.54 mm/us B. 0.501 m/s C. 1540 dB/cm D. 37.0 km/min

A. 1.54 mm/us

rayleigh scattering is an example of A. a reflector whoses size is smaller than the wavelength B. a reflector whose size is significantly larger than the wavelength C. a specular reflection D. a type of side lobe artifact

A. a reflector whose size is smaller than the wavelength

when can a patient revoke consent? A. at any time B. before the procedure begins C. never D. only prior to sedation

A. at any time

which has the greates amount of attenuation A. bone B. fat C. water D. muscle

A. bone

A single element transducer is focused A. by the manufacturer B. can not be focused C. by increasing power D. by the sonographer

A. by the manufacturer

to measure the US beam intensity, use a A. calibrated hydrophone B, lateral oscilloscope C. water filed phantom D. tissue equivalent phantom

A. calibrated hydrophone

you encounter a patient that does not speak english. which of the folowing is best to obtin informed consent? A.call for a hospital interpreter B. use sign language C. obtain it from a bilingual family member who is in the room D. point to the signiture line of the consent form and have the patient sign it

A. call for a hospital interpreter

a real time scan A. consists of many frames produced per second B. depends on how short a time the sonogrpaher takes to make a scan C. is made only between 8 am and 5 pm D. yields a gray scal image, wheras other scans yield on an m mode display

A. consits of many frames produced per second

Axial resolution is improved by A. damping B. pusling C. focusing D.refelecting

A. damping (creates less ringing, pulse is shorter)

Gain and attenuation are usually expressed in A. decibles B. decibles per centimeter C. centimeters D. centimeter per decible

A. decibles

increasing gain generally produces the same effect as A. decreasing attenuation B. increasing compression C. increasing rectification D. b and c

A. decreasing attenuation

in real time scanning, which of these choices determines the maximum frame rate? A. depth of view B. pixel sixe C. attenuation coefficient D. beam diameter E. lateral resolution

A. depth of view

impedance equals propagation speed multiplied by A. density B. stiffness C. frequency D. attenuation

A. desnity

the reflector information that can be obtained form an M-mode display inculdes___ A. distance nad motion pattern B. transducer frequency, reflection coefficient, and distance C. acoustic impedance, attenuation and motion pattern D. all of the above

A. distance and motion pattern

what is the fraction of time that a transducer is transmitting A. duty factor B. pulse duration C. period D. PRF spatial duration

A. duty factor

what increases patient exposure A. exam time B. frequency C. video taping D. wavelength

A. exam time

The operation in the signal processor that reduces noise is A. filtering B. TGC C. scan conversion D. compression

A. filtering

while scanning in a water tank, what location in a sound beam has the highest intensity? A. focal point B> focal zone C.fresnel zone D. fraunhofer zone E. half value depth

A. focal point

which of the following cannot be determined from the other? A. frequency B. amplitude C. intensity D. power

A. frequency

under which circumstances is the mechanical index the lowest? A. high freuqncy and low power B. high intensity and high frequency C. low intensity and low frequency D. low frequency and high signal amplitude

A. high frequency and low power

which of the following is a characteristic of a medium through which sound is propagating? A. impedance B. intensity C. ampitude D. frequency

A. impedance

focusing ____ A. improves lateral resolution B. improves axial resolution C. increases beam width in the focal region D. shortens pulse length

A. improves lateral resolution

increasing frequency____ A. improves resolution B. increases penetration C. increases refraction D. both a and b

A. improves resolution

all of the following statements regarding in-vitro bioeffects are true EXCEPT A. in vitro bioeffects conclusions are clinically relevant B. in vitro bioeffects are always real C. in vitro bioeffects are very important D. in vitro bioeffects may not be applicalbe to clinical settings

A. in vitro bioeffects conclusions are clinically relevant

what happens to venous return to the heart durng expiration? (in the legs) A. increased B. Decreased C. unchanged

A. increased

which of the following will result in the greatest number of shades of gray in a digital image display A. large pixels with many bits/pixel B. small pixels with few bits/pixel C. many TV lines per frame D. high contrast E. narrow dynamic range

A. large pixels with many bits/pixel

which of the following is most commonly used in ultrasound transducer? A. lead zirconate titanate B. barium sulfate C. epoxy loaded with tungsten D. quartz

A. lead zirconate titanate

how is range ambiguity artifact eliminated? A. lower PRF B. raised the PRF C. incerase the gain D. use a lower frequency transuducer

A. lower PRF

identify one of the advanatages of codd excitation A. penetration B. improved lateral resolution C. improved temporal resolution D. shorter pulse repetition period

A. penetration

if no relfection occurs at a boundary, it always means that media impedances areequal in the case of A. perpindicular incidence B. oblique incidence C. refraction D. a and b

A. perpindicular incidence

the production of a deformation form voltage is called? A. piezoelectricity B. impedance C. congeneration D. Flux

A. piezolelectricity

which of the following is associated with Power Mode Doppler A. poor temporal resolution and flash artifact B. lower sensitivity and good temporal resolution C. high sensitivity and high frame rates D. flash artifact and reduced sensitivity E. good temporal resolution and falsh artifact

A. poor temporal resolution and falsh artifact

in soft tissue: distance traveled = ____ x round trip time A. propagation speed B. wavelength C. period D. PRF

A. propagation speed

Which of the following choices best describes an ideal epidemiologic bioeffects study? A. randomized and prospective B. benifits outweigh the risk C. retrospective and optimized D. ideal and non-biased E. prudent and safe

A. randomized and prospective

what artifact is created by an object that is located depper than the image? A. range ambiguity B. shadowing C. speckle D. section thickness

A. range ambiguity

the range equation describes the relationship of A. reflector distance, propagation time and sound of speed B> distance, propagation time, and reflection coefficient C. number of cows nd sheep on a ranch D. propagation time, sound speed, and transducer frequency

A. reflector distance, propagation time, and sound of speed (pg 108)

what determines the lower and upper limits of frequency range useful in diagnostic ultraound A. resolution and penetration B. intensity and resolution C. intensity and propagation speed D. scattering and impedance

A. resolution and penetration

reflectors may be added to the display beacuse of A. reverberation B. propagation speed error C. enhancement D. oblique reflection

A. reverberation

which transucer would be best to image superficial structures A. small diameter, high frequency B. small diameter, low frequency C. large diameter. high frequency D. large diamter, low frequency

A. small diameter, high frequency (thickness of crystal determins th frequency)

the creation of an image by scanning from different angles best descirbes_____ A. spatial compounding B. finl-in interpolation C. phase quadrature D. persistence

A. spatial compounding

the axial resolution of a transducer is primarily determined by____ A. spatial pulse length B. density C. the transducer diameter D. the acoustic impedence of tissue

A. spatial pulse length

in which of these biologic tissues will sound waves propagate most quickly? A. tendon B. blood C. lung D. fat E. amniotic fluid

A. tendon

for perpendicular incidence, in medium 1, density equals 1 and propagation speed equals 3; in medium 2, desnity equals 1.5 and propagation speed equals 2. what is the intensity reflection coefficient? A. 0 B. 1 C. 2 D.3

A.0 impedance = density x propagation speed

Which of the following transducers fires the leements in groups? A. linear sequenced array B. phased array C. mechanical sector D. linear phased array

A.linear sequenced array

for a two cycle pulse of 5 MHz in soft tissue, the axial resolution is A. 0.1 mm B. 0.3 mm C. 0.5 mm D. 0.7mm

B 0.3 mm .77 x 2/5 MHz= 0.3

the attenuation of 5 MHz ultrasound in 4 cm of soft tissue i A. 5dB/ cm B.10 dB C.2.5 MHz/cm D.2 cm

B. 10 dB atten coef.= frequency/ 2 5/2=2.5 1/2 frequency x distance= 2.5x4=10 dB

what is the most typical doppler shift measured clinically? A. 3.5 MHz B. 2 kHz C. 1,000 kHz D. 20,000 kHz

B. 2 kHz (within audible range)

in soft tissue, two boundaries that generate reflections are separated in axial distance (depth) by 1 mm. with a two-cycle pulse of ultrasound, the minimum frequency that will axially resolve theres boundaries is A. 1.0 MHz B. 2.0 MHz C. 3.0MHz D.4.0MHz

B. 2.0 MHz axial resolution (mm)= 0.77 x # cycles in pulse / frequency pg 147

if the power at the output of an amplifier is 1000 times the power at the input, the gain is____ A. 60 dB B. 30 dB C. 1000 dB D. 1000 volts

B. 30 dB (10x10x10=1000...10^3)

what is the spatial pulse length for two cycles of ultraouns having a wavelength of 2 mm? A. 3 cm B. 4 mm C. 7 mm D. 1.5 mm

B. 4 mm

for perpindicular incidence, if the intensity coefficient is 96%, what is the intesnity reflection coefficient? A. 2% B. 4% C. 6% D.8%

B. 4%

depth calibration of a machine measures 100 mm spaced wires to be 90 mm apart. scanning relfectors 50 mm apart, what will the machine calculate the distance to be? A. 40 mm B. 45 mm C. 60 mm D. 65 mm

B. 45mm

for doppler, which incident angle results in no shift? A. 180 degrees B. 90 degress C. 0 degress D. 45 degress

B. 90 degress

echo intensity is represented in image memory by___ A. positive charge distribution B. a number C. electron denisty of the scan converter writing beam D. both a and c

B. a number (pg 239)

the compensation control____ A. compensates for machine instability in the warm-up time B. compensates for attenuation C. decreases patient examination time D. none of the above

B. compesnates for attenuation

the doppler shift is the ____ of two frequencies A. sum B. difference C. product D. ratio

B. difference

Which of the following determines the operating frequency of an ultrasound transducer? A. element diameter B. element thickness C. speed of sound in tissue D. element impedance

B. element thickness

which of the following improves the signal to noise ratio? A. dynamic range b. frame averaging C. gray scale D. edge enhancement E. reciever gain

B. frame averaging

an important factor in the selection of a transducer for a specific application is the ultrasonic attenution of tissue. because of this attenuation, a 7.5 MHz transducer generlly should be used for A. imaging deep structures B. imaging superficial structures C. imaging deep and shallow structures D. imaging adult intracranial structures

B. imaging superficial strucutres

when the US machine displays only strong reflecting objects and nothing else, the sonogrpaher should A. adjust far gain B. increase output power C. increase lateral resolution D. adjust TGC

B. increase output power

which of the following quantities varies most with distance from the transducer face? A. axial resolution B. lateral resolution C. frequency D> wavelength

B. lateral frequency

what type of wave is sound? A. mechanical, transverse B. mechanical, longitudinal C. transverse, longitudinal d> lateral wave

B. mechanicah, longitudina

M-mode recordings have ___ dimensions A. two spaial B. one spatial and one temporal C. one doppler and one temporal D. one doppler and one spatial

B. one spatial and one temporal

multiple reflections that are equally spaced are called A. refractions B. reverberations C. shadows D. comets

B. reverberation

the display genereally will have a dynamic range ____ that other portions of the ultrasound instrument A. larger B. smaller

B. smaller

while propagating, a sound wve is refracted. finally it returns tot he transducer. the system processes the sound waves as if it has: A. refracted and returned B. traveled in a straight line, reflecting, and returned C. traveled in a straightline, attenuated, reflected, and returned

B. taveled in a stright line, reflected and returned

the tinner the piezoelectric element, A. the lower the frequency B. the higher the frequency C. the higher the amplitue D. the lowert he amplitude

B. the higher the frequency

pulse duration is the ____ for a pulse to occur A. space B. time C. delay D. pressure

B. time

electric pulses form the pulser are applies through the delays and transmit/ receive switch to the A. pulser B. transducer C. demodulator D. display

B. transducer

enhancement is caused by: A. strongly reflecting structure B. weakly attenuating structure C. strongly attenuating structure D. frequency error

B. weakly attenuating structure

if the lear zone length of an unfocused transducer is 13 mm in diameter extends 6 cm form the trnsducer face, at which of the following distances from the face can the lateral resolution be improved by focusing the sound from this transducer? A. 13 cm B.8 cm C. 3 cm D. 9 cm

C. 3 cm needs to be closer for a better lateral resolution

the fundamental frequency of a transuder is 2.5 MHz. what is the second harmonic frequency? A. 1.25 MHz B. 4.5 MHz C. 5 MHz D. 5 cm

C. 5 MHz

a focused transducer that is 13 mm in diameter has a lateral reslution at the focus of better than A. 26 mm B. 13mm C. 6.5 mm D. depends on frequency

C. 6.5mm focus is 1/2 diameter

An echo from a 5 cm deep reflector arrives at the transducer ____ us after pulse emission A> 13 B.154 C. 65 D. 5

C. 65 (13x5)

if four shades of gray are shown on a display, each twice the brightness of the precding one, the brightest shade is ___ times the brightness of the dimmest shade A. 2 B.4 C.8 D. 16

C. 8

the near zone length for an unfocused, 5 MHz, circular transducer with a 13 mm diameter is greater than that for a 5 MHz transuder with a diameter of A. 19 mm B. 15 mm C. 9 mm D. depends on impedance

C. 9 mm

which is not part of the transducer? A. active crystal B. matching layer C. A/D converter D. wire

C. A/D converter

with which of the following is time represented on one axis? A. b mode B. b scan C. m mode D. a la mode

C. M mode

the propagation speed is greatest in A. lung B. liver C. bone D. fat

C. bone

if the frequency double, what happens to the wavelength? A. increases fourfold B. increases twofold C. decreases by one half D. frequency has no relationship to wavelength

C. decreases by one half

increasing the pulse repition frequency A. improves detial reolution B. increases maximum unambiguous depth C. decreases maximum unambiguous depth D. both a and c

C. decreases maximum unambiguous depth

the doppler shift is a measure of A. ratio of incident frequency to reflector frequency B. sum of incident frequency and reflected frequency C. difference between incident and reflected frequency D. product of incident and reflected freuencies

C. difference between incident and reflected frequency

lateral resolution is improved by A. damping B. pulsing C. focusing D. reflecting

C. focusing

place the following in order of increasing sound propagtion speed A. gas, solid, liquid B. solid, liquid, gas C. gas, liquid , solid D> liquid, gas ,solid

C. gas liquid solid

nonlinear propagation of ultrasound in tissue generates A. speckle B. attenuation C. harmonics D. refraction

C. harmonics

how does te propagation speed in bone compare wiht that in soft tissue? A. lower B. the same C. higher D. cannot say inless soft tissue is specified

C. higher

where are harmonics created A. in reciver B. in the transducer C. in the tissues D. in the beam former

C. in the tissues

a hydrophone is used to measure A. velocity B. frequency C. intensity D. phase

C. intensity

a quality assurance program A. is not needed in small labs B. is very time consuming and expensive C. is needed by all labs D. cannot be performed by the sonogrpahers

C. is needed in all labs

which of the following will result in the highest mechanical index? A. high frequency and low power B. high intensity and high freuency C. low frequency and high signal amplitude E. low intensity and low frequency

C. low frequency and high signal amplitude

ifi the propagation speed in a soft tissue path is 1.60 mm/us, a diagnostic instrument assumes a propagation speed too ___ and will show reflectors too ____ the transducer A. higher, close to B. higher, far from C. low, close to D. low, far from

C. low, close to

Gray scale display requires A. arry transducers B. cathode ray storage tubes C. morethan one bit per pixel D. b and c

C. more than one bit per pixel

if the gain of an amplifier is reduced by 3 dB and input power is unchanged, the output power of the amplifier is ____ what it was before A. equal to B. twice C. one half D. greater than

C. one half -3 db= 1/2 3 db= double

an image memory divides the cross-sectional image into A. frequencies B. bits C. pixels D. binaries

C. pixels

what is the elimination of voltages that do not exceed a certian level? A. amplification B. decompensation C. reject D. demodulation

C. reject

a small (relative to wavelength) reflector is said to ___ an incident sound beam A. focus B. speculate C. scatter D. shatter

C. scatter

which type of artifact appears most commonly with highly reflective objects? A. reverbirations B. mirroring C. shadowing D> enhancement E> defocusing

C. shadowing

you are performing a quality assurance study on an ultrasound system using a tissue equivalent phantom. you make an adjust,emt using a knob on the syste, console that changes the appearacne of the reflector brightness from fully bright to barely visible. what are you evaluating? A. resolution B. dynamic range C. system sensitivty D. vertical calibration E. slice thickness

C. system sensitivity

the lateral resolution of a transducer is primarily determined by? A. spatial pulse length B. the near field limit C. the aperture D. the acoustic impedeance of tissue

C. the aperature (where the sound beam is coming out)

the more bits per pixel A. the better the resolution B. the higher the pixel density C. the more shades of gray D. higher reliability

C. the more shades of gray

the dynamic range of an ultrasound system is defined as A. the speed with which ultrasound examination can be performed B. the range over which the transducer can be manipulated C. the ratio of the maximum to the minimum intensity that can be displayed D. the range of pulser voltages applie to the transducer

C. the ratio of the maximum to the minimum intensity that can be displayed

what is the meaning of a theraml index =3? A. tissue temperature may rise 3 degrees farenheit B. tissue temperature will rise 3 degrees celsius C. tissue temperature may rise 3 degrees celsius D. microbubbles 3 mm in diameter will burst

C. tissue temperature may rise 3 degrees celsius

the piezeoelectric effect describes how ____ is converted into ___ by a ___ A. electricity, an image, display B. incident sound, reflected sound, boundary C. ultrasound, electricity, transducer D. ultrasound, heat, tissue

C. ultrasound, electricity, transducer

with phased array transucers, the transmitted beam is steered by A. mechanically sweeping the piezoelectric elments B. mechanically rotating the piezoelectric elements C. varing the timing of pulses to the individual piezoelectric elements D. varying the frequency of pulses to the individual piezoelectric elements

C. varying the timing of pulses to the individual piezoelectric elements

what information does doppler shift provide? A. flow B. cardiac output C. velocity D. speed

C. velocity

analog voltages occur at the output of the A. beam former B. transducer C. display D. a and b

D

what is the transmitted intensity if the indcident intensity is 1 and the impedances are 1.00 and 2.64 A. 0.2 B. 0.4 C. 0.6 D. 0.8

D. 0.8

a doppler exam is performed with a 5 MHz probe and a PRF of 15 kHz. which of the these doppler shifts wil create aliasing? A. 2 kHz B. 2.5 kHz C. 7.5 kHz D. 14 kHz

D. 14 kHz (something that is over 1/2 PRF)

if gain was 30 dB and output power is reduced by one half, the new gain is ___ dB A. 15 B. 60 C. 33 D. 27

D. 27 change by half= 3 dB change 30-3=27 dB

if the spatial average intensity in a beam is 1 W/cm^2 and the transducer is 5 cm^2 in area, what is the total acoustic power? A. 1 W B. 2 W C.3 W D. 5W

D. 5W

what doppler angle is msot inaccurate? A. 15-30 degrees B. 30-45 degrees C. 45-60 degrees D. 60-75 degrees

D. 60-75 degrees

what is the standard for communication between medical imaging computers? A. ALARA B. PACS C. D-A conversion D. DICOM E. A-D converison

D. DICOM

which of the following has the lowest intensity? A. SPTP B.SATP C.SPTA D.SATA

D. SATA (averages)

if the propagation speeds of two media are equal, incidence angle equals a. the reflection angle B. the transmission angle C. the doppler anlge D. a and b

D. a and b

digital signals occur at the output of the A. beam former B. transducer C. signal processor D. a and c

D. a and c

a gray scale display shows A. gray color on a white background B. reflections with one brightness level C. a white color on a gray background D. a range of reflection amplitudes or intesnsities

D. a range of reflection amplitudes or intensities

with good images on the display but not on the printer, one should A. increase the gain B. check the scan head C. check the scan converter D. adjust the recorder

D. adjust the recoreder

increased damping produces A. increased bandqidth B. shorter pulses C. decreased efficiency D. all of the above

D. all of the above

increasing the intensity produced by the transducer A. is accompished by increasing pulser voltage B. increases the sensitivity of the system C. increases the possibility of biological effects D. all of the above

D. all of the above

the lateral resolition of an ultraound system depends on A. the aperature B. the transducer frequency C. the speed of sound in soft tissue D. all of the above

D. all of the above

Real time imaging is made possible by A. scan converters B. single element transducers C. gray scale display D. arrays

D. arrays

as frequency is increased, ____ A. wavelength increases B. a three-cycle ultrasound pulse decreases in length C. imaging depth decreases D. b and c

D. b and c

if no refraction occurs as an oblique sound beam passes through the boundary between two materials, what is unchanged aas the boundary is crossed? A. impedance B. propagation speed C. sound direction D. b and c

D. b and c

which of the follwoing improves sound transmission from the transducer element into the tissue? A. matching layer B. damping material C. coupling medium D. both a and c

D. both a and c

for perpendicular incidence, if the impedance of two media are the same, there will be no A. inflation B. reflection C. refraction D. both b and c

D. both b and c

attenuation is corrected by A. demodulation B. desegreation C. dcompression D. compensation

D. compensation

When the sound source and the receiver are not moving directly towards or away from each other, the ____ of the anlge between them enters into the calculation of doppler shift A. averag B. slope C. sine D. cosine

D. cosine

in an ultrasound imaging instrument, a flat panel display may be used as a ____ A.pulser B. digitizer C. memory D. display

D. display

fill in of an anechoic structure suchas a cyst isk nown as all of the following EXCEPT: A. partial volume articat B. slice thickness artifact C. section thickness artifact D. ghosing artifact

D. ghosting artifact

the minimum displayed axial dimension of a reflector is approximately equal to A. the beam diameter B. half the beam diameter C. twice the beam diameter D. half the spatial pulse length

D. half the spatial pulse length

which of the following produces a rectangular image format? A. vector array B. convex array C. phased array D. linear array

D. linear array

what can pulse doppler measure that continuous wave cannot A. duration B. speed C. velocity D. location E. freuency

D. location

under which circumstance is cavitation most likely to occur? A. high frequency and low power B. high intensity and high frequency C. low intesnsity and low frequency D. low frequency and high signal amplitude

D. low frequency and high signal amplitdue

which of the following is associated with cavitation? A. theraml index B. snells law B. avagadros number D. mechanical index

D. mechanical index

which of the following is determined by the pulser in an instrument? A. amplitude B. pulse repition frequency C. length of time required for a pulse to reach a specific reflector and return to the instrument D. more than one of the above

D. more than one of the above (amplitude and PRF)

in an air tissue interface, what percentage of the US is reflected? A. 0% B. near 0% C. 50% D. near 100%

D. near 100%

increasing spatial pulse length A. accompanies increases transducer damping B. is accompanied by decreased pulse duration C. improves axial resolution D. none of the above

D. none of the above

propagation speed in soft tissues ____ A. is directly proportional to frequency B. is inversly proportional to frequency C. is directly proportional to intensity D> none of the above

D. none of the above only determined by Density and Stiffness

the consolidation of many images into a sinlge frame best describes which of the following? A. dynamic range B. fill- in interpolation C. phase quadrature D. persistence

D. persistence ("temporal compounding"; color doppler going over gray scale) pg 256

The fundamental operating principle of medical ultrasound transducers is ____ A. snells law B. Doppler law C. magnetostrictive effect D. Piezoelectric effect

D. piezoelectric effect

you enter a hospital room to perform an ultrasound exam. which of the following should you do first? A. check the room number B. ask a nurse to confirm the patients name C. ask the patients visitors to leave the room D. politely check the paitnets wristband for identification

D. politely check the patients wristband for identification

the dB is defined as the ____ of two intensities A. sum B. difference C. product D. ratio

D. ratio

the scan converter changes signals from ____ to ____ format A. gray scale, color B. radio frequency, video C. b mode, m mode D. scan line, image

D. scan line, image

which of these boundaries will create the weakest reflection? A. air-lung B. air-soft tissue C. air- blood D. soft tissue- blood

D. soft tissue-blood

what artifact has a grainy appearance and is caused by the interference effects of scattered sound? A. spackle B. reverberation C. slice thickness D. speckle E. section thickness

D. speckle

axial resolution in a system equals____ A. ofur times the spatial pulse length B. the ratio of the reflector size to transducer frequency C. the maximum relector separation expected to be displayed D. the minimum reflector separation expected to be displayd

D. the minimum reflector separation expected to be displayed

where does coded excitation originate? A. the demodulator B. the flux capacitor C. the transducer D. the pulser

D. the pulser

what must be known to calculate distance to a reflector? A. attenuation, speed and density B. attenuation, impedance C. attenuation, absorption D. travel time, speed

D. travel time, speed

spatial pulse length equals the number of cycles in the pulse multiplies by A. period B. impedance C. beam width D. wavelength

D.wavelength

an ultrasound system is set at 0 dB and is transmitting at full intesnity. what is the output power when the system is transmitting at 10% of full intensity? A. -3 dB B. -50 dB C. 10 dB D. 3 dB E-10 dB

E. -10 dB

which of the following clinical modalities has the lowest output intensity? A. pulsed doppler B. CW doppler C. power doppler D. duplex scanning E. gray scale imaging

E. gray scale imaging

where does coded excitation originate? A. in the reciever B. in the tissues C. in contrast ageents D. in the matching layer E. in the pulser

E. in the pulser

T or F. there have never been biological effects from ultraound found in the labatory setting

False

phased array systems involve the sequential switching of a small goup of elements along the array T or F

False (linear sequential)

T or F. a mirror image artifact can appear along ide of the true anatomy

False ( deeper than true anatomy)

an ultrasound instrument that could represent 64 shades of gray would require an 8-bit memory. T or F

False (would be 6 bit.... 2^6= 64)

postprocessing is the process of assigning numbers to be placed in the memory T or F

Flase

T or F. a system which was working well no deos not display clear images in the far field. this may be a problm with A. transducer B. reciever C. monitor D. Scan converter

They are all true

T or F. doppler shifts always occur if the source and the observer are in motion relative to ech other and the angle between the motion an the sound beam is not 90 degrees

True

T or F. shadowing may result from high amounts of reflectors of US energy

True

what are attenuations 3 components?

absorption, reflection and scatter

the propagation speed of US in the AIUM test object is A. 1 m/s B. 1.54 m/s C. 1.54 mm/microsec D. 1 km/s

c. 1.54 mm/microsec

which of the follwoing cannot be determined form the others? A. frequency B. period C. amplitude D. wavelength

c. amplitude

attenuation along a sound path is a decrease in A. frequency B.amplitude C. intensity D. b and c

d. b and c