US Physics 1-30
Card Set Information
US Physics 1-30
What action below would be most keeping with the ALARA principle while performing a diagnostic ultrasound examination?
Complete diagnostic scan in a timely fashion at the lowest output power that achieves a quality image.
During performance of an obstetrical ultrasound exam, you adjust the system parameters to improve the image. Which of the following parameters would increase acoustic exposure?
Increase transmitting power
While performing a sonogram, to minimize risk to the fetus, which imaging mode tradeoff would be most applicable?
Use M mode instead of pulsed wave Doppler to measure the fetal heart rate.
What potential bioeffect occurs through absorption of sound energy by tissue?
When practicing universal precautions, you should do all of the following EXCEPT:
Wash gloves between exams for reuse from one patient to another.
A nosocomial infection is defined as one that is:
Thermally induced biological effects should be preventable by avoiding a local tissue temperature increase exceeding:
Which intensity descriptor has the lowest numerical value for the characterization of pulsed-wave ultrasonic field?
Increased tissue heating could occur when you:
Increases transmit power
A study designed to determine if there is an association between an adverse effect in a population and exposure to a particular agent is an?
Which of the following action is not compliant with HIPAA?
Reviewing your neighbor's medical studies on you hospital PACS system so you can give her your opinion of her condition
What does the mechanical index indicate on an ultrasound system?
The likelihood of cavitation during an ultrasound exam
In medicine, what do the initial PHI indicated?
Protected health information
What should you limit when the thermal index exceeds 1°?
To practice the ALARA principle, which of the following techniques should you employ?
Use the lowest transmit power that allows adequate tissue visualization.
The thermal index indicates:
Estimated temperature increase in tissue
Which operator control most directly adjusts the intensity of the transmitted pulse?
Acoustic output transmit power
Which of the following would show the highest intensity value?
Which intensity parameter is not applicable for continuous-wave ultrasound?
SPPA and SAPA
Which of the following would most likely have the highest SPTA value?
Using a hydrophone, you can measure:
Pressure amplitude and Duty factor
Which of the following parameters relates to tissue heating?
Which of the following occurs when you use the maximum system gain? Increase tissue heating. Increase risk of cavitation. Fluid particle streaming. Increased sound absorption.
None of the above
You are performing a sonogram and notice that the thermal index (TI) is greater than 1. Any increase in a temperature would be greatest in:
The motion of particles in a fluid is sometimes observed in an intense ultrasound beam. This is termed:
You are performing a sonogram and notice that the TI reading is 1. What does this indicate?
The output limit is high enough that temperature could increase as much as 1°C if the transducer were held stationary.
What sonographic application has the lowest FDA-approved SPTA values?
The following advantage is associated with use of the MI and TI indices:
Information is available on the screen to help the sonographer implement the ALARA principle.
When scanning with pulsed-wave Doppler, you would affect the acoustic exposure by changing which of the following?
Pulse repetition frequency
What should you do to avoid nosocomial and cross-infection with sonographic probes?
Probe cleaning should always precede high level disinfection.Disinfection using a germicide compatible with the tranducer is indicated when the probe is in contact with mucous membranes.