Eye of the tiger sign

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The eye of the tiger sign is a radiologic sign observed on T2-weighted magnetic resonance (MR) images of the brain. It appears as a central area of hyperintense signal surrounded by a ring of hypointensity in the anteromedial part of the globus pallidus. [1] The eye of the tiger sign is recognized as a diagnostic feature of pantothenate kinase associated neurodegeneration, previously known as Hallervorden-Spatz syndrome. [2] This is a neurodegenerative disorder associated with excess iron accumulation in the brain. The hypointense area is thought to be caused by the excess iron while the central hyperintensity is possibly a result of gliosis. [2]

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Hugo Spatz was a German neuropathologist. In 1937, he was appointed director of the Kaiser Wilhelm Institute for Brain Research. He was a member of the Nazi Party, and admitted to knowingly performing much of his controversial research on the brains of executed prisoners. Along with Julius Hallervorden, he is credited with the discovery of Hallervorden-Spatz syndrome. Hugo Spatz's Oberarzt, 1937–1939, Richard Lindenberg, became chief neuropathologist of the State of Maryland.

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References

  1. Guillerman, R. Paul (2000). "The Eye-of-the-Tiger Sign". Radiology. 217 (3): 895–896. doi:10.1148/radiology.217.3.r00dc31895. ISSN   0033-8419.
  2. 1 2 Chang, Chaw-Liang; Lin, Chih-Ming (2011). "Eye-of-the-Tiger sign is not Pathognomonic of Pantothenate Kinase-Associated Neurodegeneration in Adult Cases". Brain and Behavior. 1 (1): 55–56. doi:10.1002/brb3.8. ISSN   2162-3279. PMC   3217674 . PMID   22398981.