Bioimaging Exam II Review

MRI vs Ultrasound

* Image Bone
* Better resolution


* Portable
* Realtime & Fast


* Tomographic
* Functional imaging

MRI

* Image Bone
* Better resolution

Ultrasound

* Portable
* Realtime & Fast

Both

* Tomographic
* Functional imaging

MRI/Ultrasound vs Xray

Non-ionizing, functional, tomographic

T or F: Acoustic linear attenuation coefficient is a function of frequency

True

T or F: Ultrasounds use lower frequency to image deeper within tissue

\
(Think: attenuation increases with frequency)

True

As you increase the B1 field, that’s the RF pusle that affects the ________ of movement, but B1 must still be at Larmor Frequency to create resonance

Angle

The Larmor Frequency is dependent on the B__

0

T or F: MRI’s are recorded in the transverse plane

True

Helium is used in MRI to…

Cool the coil to lower resistence (preserve energy)

The frequency range of the waves used in MRI are in the _____Hz range

M

B1 is turned ____ before we record the signal -- it’s needed to excite, but turns off so it can relax and be measured.

Off