Category: Choreas (Non-Huntington's Disease)
Objective: To describe a patient with acute onset left hemiballismus secondary to a parietal stroke
Background: Acute hemiballismus is often associated with structural lesions of the basal ganglia, although a small subset of patients might develop this symptom due to the involvement of other brain regions.
Method: N/A
Results: A 62-year-old man with history of hypertension presented with acute involuntary movements of his left face, arm, and leg. These symptoms slowly improved over time, however due to persistent interference with activities of daily living he decided to seek medical attention 4 weeks later. Neurological examination was remarkable for hemiballismus of the left upper and lower extremities. Brain magnetic resonance imaging (MRI) demonstrated punctate flair hyperintensity in the right superior parietal cortex matching in DWI and ACD images, consistent with an acute ischemic stroke with no other laboratory or imaging abnormalities pointing to other causes. When seen in clinic several weeks later he had rare involuntary movements.
Conclusion: Acute hemiballismus is a classic presentation of ischemic stroke affecting the contralateral subthalamic nucleus (STN). However, a small proportion of patients with small parietal strokes causing hemiballismus have been described. Although unclear, it is hypothesized that this might be related to decreased excitatory output to STN due to the sensorimotor integration in frontoparietal lobes (1, 2). The importance of recognizing this acute syndrome lies in timely and effective treatment and mitigating unnecessary investigations geared toward uncovering alternate etiologies.
References: 1. Wu M-C, Yen R-F, Lin C-H, Wu R-M. Mystery Case: Hemiballism in a patient with parietal lobe infarction. Neurology. 2013;80(3):e22-e.
2. Laganiere S, Boes AD, Fox MD. Network localization of hemichorea-hemiballismus. Neurology. 2016;86(23):2187-95.
To cite this abstract in AMA style:
B. Maliszewski, H. Crosby, A. Samara, S. Keyrouz, D. Di Luca. Beyond the basal ganglia: acute hemiballismus secondary to a parietal stroke [abstract]. Mov Disord. 2025; 40 (suppl 1). https://www.mdsabstracts.org/abstract/beyond-the-basal-ganglia-acute-hemiballismus-secondary-to-a-parietal-stroke/. Accessed July 10, 2026.« Back to 2025 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/beyond-the-basal-ganglia-acute-hemiballismus-secondary-to-a-parietal-stroke/