MRI Annefact (cusp) Artifact
The annefact (cusp) artifact occurs when stimulated echoes originating from regions outside the field of view (FOV) are unintentionally detected by distant array coils that have not been deactivated. This artifact presents as bright ‘ghosting’ lines that extend in the phase-encode (PE) direction. The annefact artifact is commonly observed in sagittal spine imaging.
Here are some strategies to minimize or avoid Annefact (cusp) Artifact
Turn off coils outside the FOV: Ensure that the coils located outside the field of view (FOV) are properly deactivated. These distant array coils can inadvertently pick up stimulated echoes and contribute to the artifact. By turning off these coils or disabling their signal reception, you can minimize their impact on the image and reduce the occurrence of the annefact artifact.
Auto coil selection option: Many modern MRI scanners have an auto coil selection feature that automatically detects and activates only the necessary coils for a specific imaging sequence. This option helps prevent the activation of unnecessary coils located outside the FOV, which can contribute to the artifact. Enabling the auto coil selection option can aid in reducing the presence of the annefact artifact.
References:
- Zhang, Weiwei, Wu, Bing, and Lai, Yongchuan. “A Simple Method for Cusp Artifact Removal by Gradient Optimization.” Abstract #1643. GE Healthcare, Beijing, Beijing, China
- Rangwala N, Zhou XJ. Reduction of fast spin echo cusp artifact using a slice-tilting gradient. Magn Reson Med. 2010 Jul;64(1):220-8. doi: 10.1002/mrm.22418. PMID: 20572152.