HIRAYAMA-DISEASE - MR DIAGNOSIS

We report the MR findings in two cases of Hirayama disease, a kind of cervical myelopathy related to flexion movements of the neck, In flexi on MR studies, we can see the striking and pathognomonic picture of an terior shifting of posterior dura at the lower cervical spinal canal, In nonflexion studies, we find that asymmetric cord atrophy, especiall y at the lower cervical cord, though subtle, is highly suggestive of H irayama disease. When it is seen, a flexion MR study is warranted to p rove this diagnosis.