- 00000018WIA30F20970GYZ
- id_400216661.6
- Mar 2, 2022 1:07:26 PM
3-Plane Localizer
3-Plane Localizers acquire three planes in a single acquisition and display all three planes in Graphic Rx for slice, volume, SAT pulse, and tracker prescriptions. Each plane is acquired in a different pass. You can also prescribe an oblique 3-Plane Localizer from an initial 3-Plane Localizer, which can be particularly useful for prescribing slices in the true orientation of anatomy such as extremities and the heart.
A 3-Plane Localizer can only be acquired in the 2D mode. There are four localizer pulse sequences that are typically fast enough to acquire during a single breath hold. Many of the scan parameters are pre-selected.
Considerations
- Some scan parameters are automatically selected.
- If the center of the FOV, for any of the prescribed slices, falls outside of the scan range of the selected coil, a message is posted. Change the Center of FOV location or decrease the number of slices per plane.
- Normal level for dB/dt is always used to acquire a FGRE, FGRE-IR Prep and FIESTA localizer scan, regardless of the option button selected from the SAR and dB/dt screen. A SSFSE localizer scan uses the selected dB/dt option button.
- The SAR level is based on the option button selected on the SAR and dB/dt screen.
- If more than one slice is prescribed, then the FOV center coordinates represent the center slice, not the starting slice.
- A unique number of slices can be prescribed for each scan plane. For example, 3 coronal, 3 sagittal, and 15 axial images can be prescribed.
- A unique spacing value can be prescribed for each scan plane.
- As the number of slices increases, the scan time increases.
FGRE IR Prep and FIESTA Localizer selections
The FIESTA Localizer produces images with high T2/T1 ratios from three planes that can be used in Graphic Rx to define slices, SAT bands, and tracker pulse locations while visualizing their exact position in all three planes.
Use the FIESTA Localizer to acquire 3-plane images with high T2/T1 tissue contrast ratios (such as cerebral-spinal fluid, water, and fat), while suppressing signal from tissues with low T2/T1 ratios (such as muscle and myocardium).
- Use a No Phase Wrap value greater than 1.0 to avoid alias artifacts.
- Use Acoustic Reduction to significantly reduce the gradient noise for a quieter scan.
- Set the Acqs before Pause to accommodate the patient’s breath holding capability.
- Click the Advance tab to view the available User CVs. The CVs may vary based on the field strength and selected scan and imaging parameters.
- Apodization Level
FGRE Localizer selections
The FGRE Localizer produces T2*-weighted images from three planes that can be used in Graphic Rx to define slices, SAT bands, and tracker pulse locations while visualizing their exact position in all three planes.
- Use Acoustic Reduction to significantly reduce the gradient noise for a quieter scan.
- Click the Advance tab to view the available User CVs. The CVs may vary based on the field strength and selected scan and imaging parameters.
- Apodization Level
SSFSE Localizer selections
The SSFSE Localizer produces T2-weighted images from three planes that can be used in Graphic Rx to define slices, SAT bands, and tracker locations while visualizing their exact position in all three planes.
- When the Body coil is the transmit, coil the SSFSE localizer scan should be a minimum of 15 seconds to minimize SAR issues on future series.
- Use Acoustic Reduction to significantly reduce the gradient noise for a quieter scan.
- Set the Locs before Pause to accommodate the patient’s breath holding capability.
- Use ARC with compatible phased array coils to reduce the scan time.
- Click the Advance tab to view the available User CVs. The CVs may vary based on the field strength and selected scan and imaging parameters.
- Collect All Available Echoes User CV
- Invert Slice-selection Gradients User CV
- Receiver Gain