KNOW HOW TO POSITION THE SACCULE AND UTRICULE IN SCANNING

Inclusion Criteria: * Adults (≥18 years old) and minors (≥ 6 years old) * Subject having received an MRI of the internal ear canals from the HUS between 01/01/2018 and 01/01/2021 or a CT scan of the rocks between 07/01/2015 and 01/01/2021 * Normal MRI or CT on the side opposite the pathology. * Normal tonal audiogram on the side opposite the pathology (peripheral facial paralysis assumed to be cold for MRI and petrous fracture for CT). * Subject who has not expressed his opposition, after information, to the reuse of his data for the purposes of this research. * Holders of authority who have not expressed their opposition, after information, to the reuse of their child's data for the purposes of this research Exclusion Criteria: * Subject having expressed opposition to participating in the study * Holders of parental authority who have expressed their opposition to the reuse of their child's data for the purposes of this research * Imaging with artifacts * Absence of pure-tone audiogram or its abnormality on the side of the ear studied * Any malformation or pathology of the vestibule on imaging on the side of the ear studied * Subjects under guardianship or curatorship