UniSA Module 7 exam questions with correct answers

We know ultrasound is safe because a large randomised controlled trial has been undertaken. False The rate at which ultrasound passes through a unit area is called ... Intensity A bioeffect is... A physical or mechanical change caused by exposure to ultrasound As ultrasound passes through tissue, some of its energy is lost due to absorption of ultrasound energy. This results in a... Heating of the tissues Heating of tissues using ultrasound causes... Thermal bioeffects The rate of absorption in the tissues and hence the level of heating strongly depends on ... The frequency of the beam What sort of probes cause greater heating of the tissues High frequency Which mode of operation is most likely to cause substantial temperature increases in the patient's tissues? Pulses doppler The likely maximum temperature rise in the patient's tissues caused by ultrasound is the Thermal index Cavitation is a ... Mechanical bioeffect Gas bubbles are susceptible to cavitation and are regularly found in The lungs and gastrointestinal tract The maximum acceptable mechanical index (MI) is considered to be 1.9 The rate at which acoustic energy is transmitted into the medium is the acoustic Power Ultrasound intensity varies both with depth and across the beam at any given depth True