Question

As you perform an abdominal ultrasound examination, you switch from a 3.5 MHz transducer to a 7.0 MHz transducer to image a pancreatic mass. Compared to those of the previous transducer,

what will the new attenuation rate and wavelength be?
a) double attenuation, one-half wavelength
b) double attenuation rate, double wavelength
c) one-fourth attenuation rate, one-half wavelength
d) one-half attenuation rate, double wavelength
e) one-half attenuation rate, one-fourth wavelength

Answer 1

Switching to a 7.0 MHz transducer results in double the attenuation rate and half the wavelength compared to a 3.5 MHz transducer. The correct answer is (a) double attenuation, one-half wavelength.

Step-by-step explanation:

When switching from a 3.5 MHz transducer to a 7.0 MHz transducer to image a pancreatic mass, the attenuation rate will be higher and the wavelength will be shorter. Given that attenuation increases with frequency, using a higher frequency transducer like the 7.0 MHz will result in a double attenuation rate compared to the 3.5 MHz transducer.

Additionally, the wavelength of the ultrasound in tissue is inversely proportional to its frequency, so when the frequency is doubled, the wavelength is halved. Therefore, the new wavelength with a 7.0 MHz transducer will be one-half the wavelength of the 3.5 MHz transducer. The correct answer to this question is (a) double attenuation, one-half wavelength.