Fig 1.
The MED-EL Mi1200 SYNCHRONY Cochlear Implant (MED-EL, Innsbruck, Austria).
The MED-EL Mi1200 SYNCHRONY Cochlear Implant (MED-EL, Innsbruck, Austria) is compatible with MRI at a magnetic-field strength of up to 3T and with the possibility of removing the internal magnet (1a). The magnet is freely rotating (1b). In Fig 1C the magnet is in a random position, when no external magnetic field is applied and in contrast in Fig 1D the magnet aligned parallel to the external magnetic field.
Table 1.
Rating scales for the three criteria: diagnostic usefulness, artifacts and image quality.
Fig 2.
MR image series of one corpse head at 1.5T with magnet in situ.
2a: T1w MPR sagittal; 2b: T1w axial; 2c: T2w axial; 2d: T2w coronal;2e: CISS. The MR images show the maximum in diameter of the artefact in each sequence.
Fig 3.
MR image series of one corpse head at 3T with magnet in situ.
3a: T1w MPR sagittal; 3b: T1w axial; 3c: T2w axial; 3d: T2w coronal; 3e: CISS. The MR images show the maximum in diameter of the artefact in each sequence.
Table 2.
Summary of the visibility of the rated anatomical structures at the side of the cochlea implant; with and without magnet at 1.5T and 3T.
Fig 4.
MR series of corpse head at 1.5T after magnet removal with non-magnetic spacer in situ.
4a: T1w MPR sagittal; 4b: T1w axial; 4c: T2w axial; 4d: T2w coronal; 4e: CISS.
Fig 5.
MR series of corpse head at 3T after magnet removal with non-magnetic spacer in situ.
5a: T1w MPR sagittal; 5b: T1w axial; 5c: T2w axial; 5d: T2w coronal; 5e: CISS. The MR images show the maximum diameter of the artefact in each sequence.
Table 3.
Rating scale for the criteria diagnostic usefulness (inter-rater reliability: 1).
Table 4.
Rating scale for the criteria artifacts (inter-rater reliability: 1).
Table 5.
Rating scale for the criteria image quality (inter-rater reliability: 1).