Object ID: 00000018WIA30E0F870GYZ
Topic ID: id_40021467 Version: 1.4
Date: Aug 14, 2022 5:36:17 PM

3D Geometry Correction

3D Geometry Correction applies a gradient position error correction in 3 dimensions and is available with asymmetric FOVs. It is for use with large FOVs and off-center FOVs to improve image quality.

Warning

Susceptibility artifacts, such as those related to MR Conditional metal implants, will result in incorrect 3D Geometry Correction. Please carefully verify images.

3D Geometric Correction is available for all 3D prescriptions. It is disabled for 2D prescriptions under the following conditions:

Scan prescriptions with a slice gap larger than 10% of the slice thickness if selecting Spine related anatomy, Spine related anatomy, FSE family PSDs, and sagittal-oblique scan plane
Scan prescriptions with gaps between slices except for the above conditions
Scan prescriptions with a single slice
Radial slice prescriptions
Multi-group, multi-angle slice prescriptions
It is not available with PROPELLER

If 3D Geometry Correction is turned off, a conventional 2D gradwarp is applied.

Figure 1. 3D Inhance Deltaflow acquisitions

Table 1. Image legend
Number	Description
1	Image acquired with 3D Geometry Correction Off.
2	Image acquired with 3D Geometry Correction On.

The example below shows images at the edge of the volume acquired with 3D Geometry Correction turned On. Portions of the image display as blank due to the through-plane correction, which is expected behavior. The pattern and amount of the image which is blank can vary depending on the position of the acquired volume

Figure 2. Sagittal T2 Cube pelvis images

If the prescription (PSD and imaging options) are not compatible, then the selection is not available.

Images are annotated with a w to indicate 3D Geometry Correction was selected.

Figure 3. 3D Geometry Correction image annotation

3D geometry correction tradeoffs

Maximum number of slices per acquisition is reduced.
Scan reconstruction time is increased.