title: Discrepancies of MRI findings between recumbent and upright positions in atlantoaxial lesion. Report of two cases.
abstract: Two cases of atlantoaxial (A-A) instability that showed different MRI findings between supine and upright positions are presented. The upright MRI represented the findings corresponding to their symptoms. In A-A lesions, conventional MR images taken in the supine position do not always explain the pathophysiological consequences. The MR images taken in the upright position disclose the actual spinal pathophysiology with gravitational effects.
authors.affiliation: Department of Neurosurgery, Shiga University of Medical Science, Seta-tsukinowa-cho, Otsu, Shiga, 520-2192, Japan. fsuzuki@belle.shiga-med.ac.jp
authors.forename: Fumio
authors.initials: F
authors.lastname: Suzuki
authors.forename: Tadateru
authors.initials: T
authors.lastname: Fukami
authors.forename: Atsusi
authors.initials: A
authors.lastname: Tsuji
authors.forename: Kenji
authors.initials: K
authors.lastname: Takagi
authors.forename: Masayuki
authors.initials: M
authors.lastname: Matsuda
mesh_terms: D000328:Adult; D001268:Atlanto-Axial Joint / Q000293:injuries* / Q000473:pathology / Q000503:physiopathology; D001696:Biomechanical Phenomena; D002574:Cervical Vertebrae / Q000293:injuries / Q000473:pathology / Q000503:physiopathology; D003951:Diagnostic Errors / Q000517:prevention & control; D005260:Female; D019416:Head Movements / Q000502:physiology; D006801:Humans; D004204:Joint Dislocations / Q000150:complications / Q000473:pathology / Q000503:physiopathology; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000592:standards; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination / Q000592:standards; D009809:Odontoid Process / Q000293:injuries / Q000473:pathology / Q000503:physiopathology; D011187:Posture / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology; D013115:Spinal Canal / Q000473:pathology / Q000503:physiopathology; D013116:Spinal Cord / Q000473:pathology / Q000503:physiopathology; D013117:Spinal Cord Compression / Q000175:diagnosis* / Q000209:etiology* / Q000503:physiopathology; D016103:Spinal Fractures / Q000150:complications / Q000473:pathology / Q000503:physiopathology; D013124:Spinal Injuries / Q000150:complications* / Q000473:pathology / Q000503:physiopathology; D016474:Weight-Bearing / Q000502:physiology; D021801:Zygapophyseal Joint / Q000293:injuries / Q000473:pathology / Q000503:physiopathology