Hypoglycemia-induced spontaneous unilateral jerking movement in bilateral internal capsule posterior limb abnormalities.

We report an 89-year-old woman who developed consciousness disturbance associated with marked hypoglycemia, and showed involuntary movements manifested as spontaneous quick-jerking flexion followed by slow relaxation, in the right leg. Diffusion-weighted imaging revealed bilateral hyperintensities in the posterior limbs of the internal capsule (P-IC). She was treated with intravenous glucose supplementation, and her symptoms dramatically improved. The P-IC lesions are common abnormalities on MRI in hypoglycemia, and may cause paralysis. However involuntary movements associated with the lesions are rarely observed. The spontaneous jerking movements observed in this patient might result from transient impairment of the pyramidal tract associated with hypoglycemia.