Spokes per Segment

Select a Spokes per Segment for Silenz acquisitions.

• As the Spokes per Segment increases, in general the scan time decreases.

Silenz is a 3D gradient echo imaging sequence that gently steps the gradients during the MR acquisition to minimize gradient induced vibration and noise during scanning. It uses very short TE values and low flip angle values to generate PD-weighted images. An IR-Prepared pulse can be added to generate T1-weighted image contrast.

A radial center-out k-space encoding scheme arranges the acquisition order such that adjacent spokes are sequentially acquired one-by-one. The gradient ramp up/down can be eliminated between two spokes when the jump is smaller than the system capability resulting in a quiet technique.

Table 1. Image legend

Number	Description
1	The acquisition is comprised of multiple intersecting spokes rather than a uniform rectilinear grid. The arrow is pointing at a single spoke.
2	The end point of each spoke follows a spiral path in time. The spiral path includes all the segments.

A reconstruction technique incorporates 3D re-gridding and a k-space density correction at the k-space center. The result is a radial encoding scheme that generates volumetric (3D) data in all three planes (X, Y, Z). The images can be automatically reformatted into axial, sagittal, and coronal planes.