Answer :
Final answer:
Lower frequencies are indeed used for deeper tissue scanning because they can penetrate further into the body than higher frequencies, which offer more detail but less penetration.
Explanation:
Yes, you generally use lower frequencies for deeper tissue scanning. This is because lower frequency ultrasound waves penetrate deeper into the body compared to higher frequencies, which provide greater detail but have limited penetration. For example, a frequency of 7 MHz used in ultrasound has a penetration limit of about 0.11 m in tissue which equates to the ability to effectively scan to a depth of approximately 500 times the wavelength limit of 0.22 mm.
On the other hand in treatments like ultrasound diathermy, frequencies of 0.8 to 1 MHz are typical for deep-heat therapy, highlighting the use of lower frequencies for deep tissue applications. Meanwhile higher frequencies might be used in smaller organs like the eye where deep penetration is not required.
