Cerebral Blood Flow in a Patient with Hemiballism

An 88-year-old woman presented with hemiballism of abrupt onset that mainly affected her left leg. Brain computed tomography revealed a hemorrhage at the right subthalamic nucleus (Picture 1). An easy Z-score imaging system analysis of single photon emission computed tomography (SPECT) using Tc-ethyl cysteinate dimer revealed hyperperfusion at the right motor cortex corresponding to the leg and the right thalamus (Picture 2). Cerebellar hyperperfusion was observed in 48/50 patients who received this test in our hospital, which suggests the existence of a technical problem. No change of blood flow (CBF) was detected in the subthalamic nucleus. Somatotopic organization was observed in the subthalamic nucleus (1). However, this nucleus was too small to observe CBF changes within the nucleus. An increased glucose uptake in the contralateral motor cortex was reported in a case of hyperglycemic hemiballism (2). SPECT is also useful for revealing the mechanism of hemiballism.