Contrast enhanced MRI in Hirayama disease

Full text: HD is a very rare condition characterized by asymmetric distal upper limbs muscle weakness and atrophy in the C8-T1 distribution without sensory or pyramidal signs. Classically, adolescent males develop initially progressive weakness followed by spontaneous stabilization within several years after onset. The pathogenesis of the disease is unclear and pathologic studies are lacking. However the prevailing theory postulates that insufficient growth of the dura relative to the spinal column during puberty allows forward displacement of the dura in flexion with compression of the spinal cord, possibly leading to ischemia of the anterior horn cells at C8 and Th1. Most reported cases have been from Asia, particularly Japan, though some have been reported from India, the Middle East, and Europe. To date, and to our knowledge, there has been no published study characterizing the MR imaging features of this disease in Bulgaria. Routine MR imaging of patients with HD has shown segmental cord atrophy, rarely associated with Th2 abnormalities. Previous studies of other cord diseases have shown, that the extent of cord tissue damage is usually underestimated by using routine MR imaging and that brain plasticity might limit the clinical consequences of cord injury. In this study, we used a multiparametric MR imaging approach to investigate in a patient with HD