ABSTRACT
An 11-year-old male patient developed weakness or right arm elevation after sudden movement at the age of eight. Reflex epilepsy was initially suspected; however, magnetic resonance imaging and electroencephalography (EEG) revealed no abnormality. Video-EEG monitoring was performed, but no change was noted during attacks of weakness. He was diagnosed with paroxysmal kinesigenic dyskinesia (PKD) and carbamazepine has stopped his attacks. PKD is a rare neurological disorder characterized by brief attacks of involuntary movement triggered by sudden voluntary movements, which may be confused with reflex epilepsy. PKD should be considered as a differential diagnosis of reflex epilepsy.
Subject(s)
Epilepsy, Reflex , Child , Diagnosis, Differential , Dystonia , Humans , Magnetic Resonance Imaging , MaleABSTRACT
Several structures including subthalamic nucleus (STN), the caudal zona incerta (cZI), the prelemniscal radiation (Raprl), and the thalamic ventral intermediate nucleus (Vim) have been reported to be useful for improving symptoms of Parkinson's disease (PD). However, the effect of each target is still unclear. Therefore, we investigated each structure's effects and adverse effects using a directional lead implanted in the posterior STN adjacent to the cZI and Raprl in two patients with tremor-dominant PD. In Case 1, maximal reduction of tremor was obtained by stimulation toward the Vim, and stimulation toward the thalamic reticular nucleus (TRN) reduced verbal fluency, but did not induce dysarthria. In Case 2, maximal reduction of tremor was obtained by stimulation toward the dorsal STN and Raprl. Maximal reduction of rigidity was achieved by stimulation toward the dorsal STN, Raprl, and cZI. Bradykiensia was improved by stimulation in all directions, but dyskinesia and dysarthria were evoked by stimulation toward the dorsal STN and cZI. The directional lead may elucidate the stimulation effect of each structure and broaden target selection depending on patients' symptoms and adverse effects.
