Volumetric navigators (vNavs) interleaved within longer MRI sequences are an effective method for dynamically detecting and correcting head motion during the acquisition. However, motion is estimated by registering each vNav back to the first, and bias can be introduced by non-rigid deformations of, e.g., the mouth, since the head is taken to be a rigid body. We demonstrate that this bias introduces correction-related artifacts. We present robust real-time brain extraction (0.02 s per vNav) and demonstrate offline that the bias and associated artifacts can be removed by using motion tracks from brain-masked registration.
How to access this content:
For one year after publication, abstracts and videos are only open to registrants of this annual meeting. Registrants should use their existing login information. Non-registrant access can be purchased via the ISMRM E-Library.
After one year, current ISMRM & ISMRT members get free access to both the abstracts and videos. Non-members and non-registrants must purchase access via the ISMRM E-Library.
After two years, the meeting proceedings (abstracts) are opened to the public and require no login information. Videos remain behind password for access by members, registrants and E-Library customers.
Keywords