'Snake eyes' MRI sign: possible role of cobalt toxicity?

‘Snake eyes’ sign is the magnetic resonance imaging (MRI) occurrence of bilateral hyperintensities of the anterior horns of spinal cord on axial T2-weighted MR images. This neuroradiological sign has been commonly attributed to lower motor neuron (LMN) syndromes, such as Hirayama disease, but also in cervical spondylotic myelopathy and spinal cord infarction. We report on a patient with upper limb LMN syndrome and MRI snake eyes sign secondary to cobalt neurotoxicity.