Neuroimaging of Hemichorea-Hemiballism

Background: Hemichorea-Hemiballism (HCHB) can be caused by various diseases such as cerebrovascular disease, hyperglycemia, tumor, and inflammatory diseases. However, there are a few case studies using functional imaging such as single photon emission computed tomography (SPECT). Methods: In this study, we included patients with HCHB. The patients with hyperglycemia over 250 mg/dl or high signal intensity on T1 weighted imaging were excluded. Clinical and neuroimaging characteristics of the patients were obtained and analyzed. Results: We included 20 patients (M:F=12:8, mean age=67.1±15.3). Sixteen patients were presented with hemiballism and four with hemichorea. Six patients had no structural lesions causing HCHB. Subthalamic nucleus was the causative lesion in 6 patients. Other lesions associated with HCHB were basal ganglia, thalamus, and cortices. In a patient without structural lesion, anti-double stranded DNA antibody was detected. Brain SPECT showed not only perfusion abnormalities in the cases without structural lesions but also additional abnormalities in those with definite lesions. Conclusions: Various mechanisms were related to the development of HCHB. Functional imaging such as SPECT and immunological work-up is needed to investigate the underlying pathomechanism of HCHB. J Korean Neurol Assoc 25(3):318-323, 2007