抄録
In a 15 year-old girl with good health from birth, a thoracic spinal tumor was detected on a routine chest roentgenogram. The neurological examination was normal, however the plain chest roentgenogram showed a left mediastinal mass. Myelogram showed the incomplete block of dye column around Th10. Isovist CT scan revealed the extradural tumor, which destructed part of the left Th10 vertebral arch and transverse process. Axial images of MRI finely showed the extradural and paravertebral tumor, which existed in the Th10 vertebral body anterolaterally. Although the tumor protruded into the pleura and beside the descending aorta, it didn't compress the dural theca. Cubic configuration of a dumb-bell tumor, in the case of differential development, was possibly grasped by MRI, and such examinations were very useful for the operation. In the present case, a thoracic spinal dumb-bell tumor could be removed without difficulty by costotransversectomy, and the postoperative course was well.
