SONOGRAPHY CANADA – CORE EXAM QUESTIONS
AND ANSWERS GRADED A+ LATEST UPDATE.
what is the I SPPA for mechanical bioeffects? ANS >>> 190W/cm^2
what is the I SPTA for thermal bioeffects? ANS >>> 720mW/cm^2
recommended MI for fatal scanning ANS >>> MI < 1.9
recommended TI for fatal scanning ANS >>> TI < 0.7
after what fatal age is safe to use PW doppler? ANS >>> 14 weeks
what does ALARA stand for ANS >>> as low as reasonably
achievable
,frequency ANS >>> # of cycles/second
f = 1/p
period ANS >>> time it takes for 1 cycle to occur (use)
P = 1/f
wavelength ANS >>> length of 1 cycle (mm)
wavelength = c/f
inversely proportionate to frequency
assumed speed of sound in soft tissue ANS >>> 1540 m/s
1.54mm/use
intensity ANS >>> I = power/area
measured in Watts
proportionate to amplitude squared
range equation ANS >>> distance to reflector = 1/2 speed of sound
x GRT
, go return time (GRT) ANS >>> 13usec for 1cm of depth
acoustic impedance (z) ANS >>> difference between media
determining % reflection and % transmission of sound (Rayls)
z= density x speed of sound
z=pxc
% reflection equation ANS >>>
larger AI difference results in ___ reflection ANS >>> greater
pulse duration (PD) ANS >>> time for one pulse
Tx is ringing
PD = period x n; n = # of cycles in pulse
pulse repetition period (PRP) ANS >>> the time from the beginning
of one pulse to the beginning of the next
time Tx is ringing and listening for 1 scan line
PRP = 13usec/cm x imaging depth
AND ANSWERS GRADED A+ LATEST UPDATE.
what is the I SPPA for mechanical bioeffects? ANS >>> 190W/cm^2
what is the I SPTA for thermal bioeffects? ANS >>> 720mW/cm^2
recommended MI for fatal scanning ANS >>> MI < 1.9
recommended TI for fatal scanning ANS >>> TI < 0.7
after what fatal age is safe to use PW doppler? ANS >>> 14 weeks
what does ALARA stand for ANS >>> as low as reasonably
achievable
,frequency ANS >>> # of cycles/second
f = 1/p
period ANS >>> time it takes for 1 cycle to occur (use)
P = 1/f
wavelength ANS >>> length of 1 cycle (mm)
wavelength = c/f
inversely proportionate to frequency
assumed speed of sound in soft tissue ANS >>> 1540 m/s
1.54mm/use
intensity ANS >>> I = power/area
measured in Watts
proportionate to amplitude squared
range equation ANS >>> distance to reflector = 1/2 speed of sound
x GRT
, go return time (GRT) ANS >>> 13usec for 1cm of depth
acoustic impedance (z) ANS >>> difference between media
determining % reflection and % transmission of sound (Rayls)
z= density x speed of sound
z=pxc
% reflection equation ANS >>>
larger AI difference results in ___ reflection ANS >>> greater
pulse duration (PD) ANS >>> time for one pulse
Tx is ringing
PD = period x n; n = # of cycles in pulse
pulse repetition period (PRP) ANS >>> the time from the beginning
of one pulse to the beginning of the next
time Tx is ringing and listening for 1 scan line
PRP = 13usec/cm x imaging depth
