MRI DIAGNOSIS OF INTRAMEDULLARY METASTASES FROM EXTRA-CNS TUMORS

The purpose of this study was to evaluate the topography, morphology a nd contrast enhancement of the intramedullary metastases (IM) from ext ra-CNS neoplasms. We report the results of a multicenter retrospective study on 18 patients with 26 IM examined with a 0.5T MR imaging syste m; intravenous injection of Gd-DTPA was performed in all cases. We fou nd that the lesions are most frequently single, oval shaped, and small , with little or no deformation of the spinal cord (14 of 26 IM). They appear isointense on spin-echo T1-weighted images (24 of 26 IM), with a homogeneous and generally nodular high contrast enhancement after G d-DTPA injection (21 of 26 IM), and present on T2- and proton-density- weighted sequences with a pronounced perilesional, pencil-shaped hyper intensity of the surrounding cord which is more evident in the cranial part of the cord referring to the IM.