"So, if the acoustic power of the ultrasound beam is enough to raise the tissue temperature by 1.0°C, then the thermal index = 1.0. It should be noted that this is a relative risk of heating, not an absolute scale of tissue heating."
"Wp is the relevant (attenuated) acoustic power at the depth of interest and"
"Wdeg is the estimated power necessary to raise the tissue equilibrium temperature by one degree Celsius"
"For obstetric and neonatal scanning there is no known reason to restrict scanning times with a TI value between 0-0.7. TI values between 0.7-3.0 are time restricted depending on the age of the fetus and tissue being scanned."
Expected headings
"Recommendations"