The owl's eye sign represents bilaterally symmetric circular to ovoid foci of high T2-weighted signals in the anterior horn cells of the spinal cord and is seen on axial MR imaging. The sagittal corollary is a "pencil-like" vertical linear high T2-weighted signal extending usually over a number of segments.
Although typically described as one of the patterns in spinal cord infarction affecting the anterior spinal artery 1,2, it is seen in multiple other clinical settings, and represents the result of increased metabolic activity (thus vulnerability) and reduced collateral supply of the anterior horns of the spinal cord. An owl's eye pattern is seen in the following scenarios:
- 1. Masson C, Pruvo JP, Meder JF et-al. Spinal cord infarction: clinical and magnetic resonance imaging findings and short term outcome. J. Neurol. Neurosurg. Psychiatr. 2004;75 (10): 1431-5. J. Neurol. Neurosurg. Psychiatr. (full text) - doi:10.1136/jnnp.2003.031724 - Free text at pubmed - Pubmed citation
- 2. Novy J, Carruzzo A, Maeder P et-al. Spinal cord ischemia: clinical and imaging patterns, pathogenesis, and outcomes in 27 patients. Arch. Neurol. 2006;63 (8): 1113-20. doi:10.1001/archneur.63.8.1113 - Pubmed citation