title: Hirayama disease: MR diagnosis.
abstract: We report the MR findings in two cases of Hirayama disease, a kind of cervical myelopathy related to flexion movements of the neck. In flexion MR studies, we can see the striking and pathognomonic picture of anterior shifting of posterior dura at the lower cervical spinal canal. In nonflexion studies, we find that asymmetric cord atrophy, especially at the lower cervical cord, though subtle, is highly suggestive of Hirayama disease. When it is seen, a flexion MR study is warranted to prove this diagnosis.
authors.affiliation: Department of Diagnostic Radiology, Chang Gung Memorial Hospital and Medical College, Taipei, Taiwan, Republic of China.
authors.forename: C J
authors.initials: CJ
authors.lastname: Chen
authors.forename: C M
authors.initials: CM
authors.lastname: Chen
authors.forename: C L
authors.initials: CL
authors.lastname: Wu
authors.forename: L S
authors.initials: LS
authors.lastname: Ro
authors.forename: S T
authors.initials: ST
authors.lastname: Chen
authors.forename: T H
authors.initials: TH
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D002574:Cervical Vertebrae / Q000473:pathology; D003937:Diagnosis, Differential; D019416:Head Movements / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D013116:Spinal Cord / Q000473:pathology; D014897:Spinal Muscular Atrophies of Childhood / Q000175:diagnosis*