Two Cases of Intradural Neurinoma with Large Cysts.

Neurinoma is the most common spinal cord tumor. However neurinoma with large cystic changes are rare. We experienced two cases of this condition in the lumbar spine: A 53-year-old male suffering from low back pain and bilateral buttock and thigh numbness; and a 40-year-old female complaining of low back and left lower limb pain and pollakisuria. The MR images of both cases showed an intradural tumor with large cystic change, which represented low signal in T1-weighted images and high signal in T2-weighted images. In the contrast MR images of case 2 the cyst wall was clearly enhanced with Gd-DTPA. Both tumors were removed surgically and pathologically diagnosed as Antoni-B type neurinoma.No evidence of any postoperative neurological defect was shown.Contrast-enhaced MR images should be taken to differentiate between a cystic neurinoma and an arachnoidal cyst.