Investigation of a medullar pathology, whether cervical, dorsal or of the conus medullaris, is performed using magnetic resonance. It is the only imaging method capable of performing this assessment and offers excellent sensitivity. MRI is used to analyze the signal and enhancement of the lesion, evaluate its extent, as well as its possibly contributive adjacent structures; for example, in the case of spinal stenosis with secondary myelomalacia focus or medullary compression caused by vertebral metastatic disease. Magnetic resonance imaging helps diagnose demyelinating lesions, myelomalacia, myelites of various etiologies and intramedullar or dural tumors.