Repetitive involuntary leg movements in patients with brainstem lesions involving the pontine tegmentum: evidence for a pontine inhibitory region in humans.

Repetitive involuntary limbs movements have been mostly reported in patients with extensive brainstem pathologies, but the region responsible is unknown. We describe two patients with progressive basilar artery infarcts who showed automatic stepping and one patient with an osmotic demyelination disorder who showed periodic involuntary leg movements. By subtracting diffusion-weighted images before and after the development of repetitive involuntary leg movements, the brainstem lesion responsible for the involuntary movements was distinctively located in the vicinity of the pontine tegmentum, which is known as the pontine inhibitory region in animal studies.