How to decrease intravoxel dephasing and increase SNR?

How to decrease intravoxel dephasing and increase SNR?

How to decrease intravoxel dephasing and increase SNR: Decrease the voxel size (increase spatial resolution), either by increasing the matrix ( trade-off: will reduce signal-to-noise ratio [ SNR ]) or by reducing the FOV ( trade-off: may cause wraparound). Only gold members can continue reading.

Why is there no signal in turbulent flow?

In turbulent flow (with Re >2100), random flow exists that contains different velocity components (i.e., with different speed and direction of flow). Consequently, each of these components has different phases that tend to cancel each other out and result in no signal (flow void).

How to decrease the voxel size in radiology?

Decrease the voxel size (increase spatial resolution), either by increasing the matrix ( trade-off: will reduce signal-to-noise ratio [ SNR ]) or by reducing the FOV ( trade-off: may cause wraparound). Only gold members can continue reading. Log In or Register to continue

Where does turbulent flow occur in the brain?

In brain turbulent flow is often seen in the aqueduct of Sylvius, the fourth ventricle and is sometimes seen from transmitted motion from arteries. Turbulence dephasing can be reduced by shorter TE sequences and smaller voxel volume, decreased slice thickness or higher matrix. 2.

How is turbulence dephasing reduced in a MRI?

Turbulence dephasing can be reduced by shorter TE sequences and smaller voxel volume (decreased slice thickness or higher matrix). The most common source of artifact in MRI is motion of the subject.

What happens to signal loss in turbulent flow?

Turbulent flow results in a broader spectrum of proton velocities and a wide range of flow directions that are not seen in typical laminar flow. The varied flow velocities and directions result in more rapid dephasing and signal loss termed “intravoxel dephasing.”

How to decrease intravoxel dephasing and increase SNR: Decrease the voxel size (increase spatial resolution), either by increasing the matrix ( trade-off: will reduce signal-to-noise ratio [ SNR ]) or by reducing the FOV ( trade-off: may cause wraparound). Only gold members can continue reading.