Intradural spinal cord lesions: Gd-DTPA-enhanced MR imaging

Twenty-five patients with suspected spinal cord neoplasms were studied with high-field-strength magnetic resonance (MR) imaging (1.5 T) before and after administration of gadolinium diethylenetriamine-pentaacetic acid (DTPA) (gadopentetate dimeglumine). Five patients had enhancing, nonneoplastic lesions, including spinal dural arteriovenous fistulas (AVFs), cord infarction, and chronic arachnoiditis. Fifteen patients had proved spinal cord neoplasms, 13 intramedullary and two extramedullary. Four of the intramedullary tumors were detected only after Gd-DTPA administration; in five others, contrast material enhancement improved observer confidence. Gd-DTPA also demonstrated one dural AVF not detected on precontrast images. Regions of cord ischemia or infarction related to spinal dural AVF also enhanced in three patients. Advantages of Gd-DTPA include the demonstration of small isointense intramedullary tumors and the ability to permit differentiation of tumor from adjacent cord syrinx and solid tumor from postoperative gliosis and arachnoid scarring. Gd-DTPA enhancement is a useful adjunct to high-resolution MR imaging of the spinal cord.