Fig. 2From: Ultra high-field SWI of the substantia nigra at 7T: reliability and consistency of the swallow-tail signInconsistent occurrence of the swallow-tail sign in healthy subjects. a-c Clearly definable swallow-tail of the dorsolateral SNc. d The swallow-tail can only be identified on the right side (filled arrow). e-f No swallow-tail sign can be detected (arrows)Back to article page