Parameters Flashcards
acoustic intensity
the amplitude (height) of the wave
period
the time needed to complete a single oscillation cycle from peak to peak
acoustic frequency
1/period (period=time of single oscillation peak-to-peak)
stimulus duration
the total duration of a single sonication stimulus
duration can be pulsed (with pauses included) or continuous
burst duration
period of acoustic sonication from start to end of a single oscillation
also called tone-burst duration or pulse duration
in pulsed paradigms only
burst repetition period
the period between the starting point of two consecutive sonications; or the sum of 1 burst duration and 1 pause between consecutive burst durations sonications
pulse repetition frequency
a measure of how many individual pulses are occurring per second. pulses occur within bursts.
(1/burst repetition period)
duty cycle
the amount of time per second that is covered by actual pulses
DC=1 for continuous
(burst duration/burst repetition period)
cycles per burst
number of cycles that occur in a single burst
acoustic frequency x burst duration
number of pulses
how many pulses are occurring per second times the total number of seconds
(pulse repetition frequency x stimulus duration)
Isppa
intensity, spatial peak pulse average (W/cm2)
the average intensity of an individual pulse
Ispta
intensity, spatial peak temporal average (mW/cm2)
intensity averaged over the total experimental time, including inter-stimulus intervals
FDA guideline for Isppa
less than 190 W/cm2
FDA guideline for Ispta
less than 720 mW/cm2
FDA guideline for mechanical index
less than 1.9
mechanical index
description of non-thermal mechanical bioeffects
Focus at .5 MHz?
about 3 mm
Peak instantaneous pressure
MPa, megapascals
ARF
acoustic radiation force
the result of tissue removing momentum from the wave resulting in force on the tissue
acoustic cavitation
the generation of spaces and bubbles within tissue due to the tensile phase of an acoustic wave exceeding a threshold.
the threshold depends on peak negative pressure, frequency, and duration, as well as tissue properties
Ispba
spatial-peak, burst average (W/cm2)
intensity averaged over 1 burst including spaces between individual pulses
