TY - JOUR
T1 - Safety Assessment of Advanced Imaging Sequences II: Simulations
AU - Jensen, Jørgen Arendt
N1 - (c) 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.
PY - 2016
Y1 - 2016
N2 - An automatic approach for simulating the emitted
pressure, intensity, and MI of advanced ultrasound imaging sequences
is presented. It is based on a linear simulation of pressure
fields using Field II, and it is hypothesized that linear simulation
can attain the needed accuracy for predicting Mechanical Index
(MI) and Ispta.3 as required by FDA. The method is performed on
four different imaging schemes and compared to measurements
conducted using the SARUS experimental scanner. The sequences
include focused emissions with an F-number of 2 with 64 elements
that generate highly non-linear fields. The simulation time is
between 0.67 ms to 2.8 ms per emission and imaging point,
making it possible to simulate even complex emission sequences
in less than 1 s for a single spatial position. The linear simulations
yield a relative accuracy on MI between -12.1% to 52.3% and for
Ispta.3 between -38.6% to 62.6%, when using the impulse response
of the probe estimated from an independent measurement. The
accuracy is increased to between -22% to 24.5% for MI and
between -33.2% to 27.0% for Ispta.3, when using the pressure
response measured at a single point to scale the simulation.
The spatial distribution of MI and Ita.3 closely matches that
for the measurement, and simulations can therefore be used
to select the region for measuring the intensities, resulting in
a significant reduction in measurement time. It can validate
emission sequences by showing symmetry of emitted pressure
fields, focal position, and intensity distribution.
AB - An automatic approach for simulating the emitted
pressure, intensity, and MI of advanced ultrasound imaging sequences
is presented. It is based on a linear simulation of pressure
fields using Field II, and it is hypothesized that linear simulation
can attain the needed accuracy for predicting Mechanical Index
(MI) and Ispta.3 as required by FDA. The method is performed on
four different imaging schemes and compared to measurements
conducted using the SARUS experimental scanner. The sequences
include focused emissions with an F-number of 2 with 64 elements
that generate highly non-linear fields. The simulation time is
between 0.67 ms to 2.8 ms per emission and imaging point,
making it possible to simulate even complex emission sequences
in less than 1 s for a single spatial position. The linear simulations
yield a relative accuracy on MI between -12.1% to 52.3% and for
Ispta.3 between -38.6% to 62.6%, when using the impulse response
of the probe estimated from an independent measurement. The
accuracy is increased to between -22% to 24.5% for MI and
between -33.2% to 27.0% for Ispta.3, when using the pressure
response measured at a single point to scale the simulation.
The spatial distribution of MI and Ita.3 closely matches that
for the measurement, and simulations can therefore be used
to select the region for measuring the intensities, resulting in
a significant reduction in measurement time. It can validate
emission sequences by showing symmetry of emitted pressure
fields, focal position, and intensity distribution.
U2 - 10.1109/TUFFC.2015.2499776
DO - 10.1109/TUFFC.2015.2499776
M3 - Journal article
C2 - 26571524
SN - 0885-3010
VL - 63
SP - 120
EP - 127
JO - IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control
JF - IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control
IS - 1
ER -