Irreversible chorea as the initial presentation of polycythemia rubra vera in an elderly woman

T2 weighted Axial view Magnetic resonance imaging showing A) No infarct or space occupying lesion in the Caudate nucleus (large white arrow), putamen (small white arrow) or the Globus pallidus (black arrow), B) DWI image showing no hyperintensity to suggest acute vascular event in the Basal Ganglia (white arrows), C) The Acute diffusion coefficient MRI sequence showed no diffusion restriction in the Caudate nucleus (large black arrow), putamen (small black arrow) or Globus pallidus (white arrow).