Eye-of-the-Tiger sign is not Pathognomonic of Pantothenate Kinase-Associated Neurodegeneration in Adult Cases

An eye-of-the-tiger sign is previously known to have one-to-one correlation with pantothenate kinase-associated neurodegeneration (PKAN). Reviewing the literature on this subject, the correlation between eye-of-the-tiger sign and PKAN seems to show an interesting hypothesis that differs from conventional conclusion. We analyze the published papers in an attempt to reflect this trend and illustrate our points with findings in a 39-year-old man. His brain magnetic resonance imaging study shows typical eye-of-the-tiger sign suggestive of PKAN. Genetic analyses revealed no mutations in pantothenate kinase 2.