Abstract
Paroxysmal kinesigenic choreoathetosis (PKC) is a rare and benign disorder with its onset in childhood. PKCgenerally improves with age, and its pathophysiology has not been revealed.
We recorded both ictal and interictal SPECT in a 14-year-old girl with PKC. Ictal SPECT showed a significantdecrease in blood flow in the caudate nucleus contralateral to the limb showing an involuntary movement.
We also examined paired-pulse stimuli somatosensory evoked potential (SEP) of the same patient. Recoverypattern of P25 and N33 components was normal and comparable to 5 healthy volunteers, suggesting the absence ofcortical hyperexcitability.
These results suggest dysfunction or immaturity of the indirect pathway of basal ganglia in PKC, as well asthehyperexcitability of the descending pathway.
