Teaching NeuroImages: "Penguin" or "hummingbird" sign and midbrain atrophy in progressive supranuclear palsy.

Jerome J. Graber, MD, MPH Robert Staudinger, MD, FAAN An 82-year-old man presented to us with a 2-year history of progressive difficulty walking. On examination, he had bradykinesia, bradyphrenia, axial rigidity without appendicular rigidity, cogwheeling, or tremor, and restriction of upward and downward gaze. Imaging revealed prominent midbrain atrophy without pontine atrophy, referred to as the “penguin” or “hummingbird” sign (figure), which may be helpful in distinguishing progressive supranuclear palsy from multisystem atrophy, Parkinson disease, and healthy controls.1,2