Chorea is a type of hyperkinetic movement, referring to involuntary, irregular, aimless, nonrhythmic, abrupt, rapid, unsustained movements. The term hemichorea refers to chorea of one side of the body. A 39-year-old woman presented with a three-week history of abrupt, involuntary movements of her right hand and right foot, which was compatible with hemichorea of the right side. MRI brain showed a 1.7x1.5x1.3 cm lesion in the posterior limb of the left internal capsule and the lateral part of the left thalamoganglionic region, which was seen as mixed iso-and hyperintense in T1W images, and heterogeneous and hyperintense in T2W/ FLAIR images. T2 gradient sequences showed a peripheral rim of decreased signal intensity, which is the hemosiderin ring, and no significant brain edema. Partial contrast enhancement of the lesion after contrast media injection suggested cavernous angioma. After medical treatment with haloperidol 2.5 milligrams per day, her symptom gradually improved within 2 months.

Keywords: Chorea, Choreiform movement, Hemichorea, Cavernoma, Cavernous angioma