Acute Hemichorea-Hemiballismus Following COVID-19 (AZD1222) Vaccination

Video S1. Case 1: An 88-year-old male presented 16 days after the first dose of AZD1222 having been awoken by involuntary movements of the left arm, leg and face that worsened throughout the day. The video demonstrates continuous, non-patterned small amplitude (choreiform) movements seen in the patient's left arm and leg. Large proximal movements (not shown in the video) were also identified on examination.

Video S2. Case 2: An 84-year-old male who presented 40 days following the first dose of AZD1222 with acute onset of involuntary hyperkinetic movements of the left upper and lower limbs noted initially whilst watching television, worsening through the evening, and interfering with sleep. This video was taken the following day after partial spontaneous improvement, but still demonstrating small amplitude, non-patterned (choreiform) movements of the left side. Occasional large amplitude, proximal movements are seen, along with attempts to mask or augment the choreiform movements with semi-purposeful actions.

Figure S1. Representative MRI slices from Case 1 obtained using a 3 Tesla scanner. Top row: Axial Diffusion-weighted imaging sequence. Middle row: Axial T2-weighted Fluid Attenuated Inversion Recovery (T2-FLAIR) Sequence. Bottom row: Axial T2*-weighted angiography sequences. No acute neurological lesions were detected on imaging following review by two expert neuroradiologists.

Figure S2. Representative MRI slices from Case 2 obtained using a 3 Tesla scanner. Top row: Axial Diffusion-weighted imaging sequence. Middle row: Axial T2-weighted sequence. Bottom row: Axial T2*-weighted angiography sequences. No acute neurological lesions were detected on imaging following review by two expert neuroradiologists.