Schmidt MA, et al. - Here, the authors assess whether the swallow-tail sign occurs consistently in healthy subjects and if it can be reliably detected with high-resolution 7T susceptibility weighted imaging (SWI). They conclude that this sign can be reliably detected. The data, however, suggest its occurrence is not consistent in healthy subjects. One reason for this occurrence can be an individually variable molecular organization of nigrosome 1 so that it does not return a uniform signal in SWI.