Paroxysmal kinesigenic dyskinesia (PKD) is a rare type of paroxysmal dyskinesia with a population estimated incidence of 1/150, 000. PKD is likely correlated with genetics. Genetic studies have shown that, in addition to PRRT2 gene, mutations in SCN8A, KCNA1, CHRNA4, DEPDC5, PNKD, SLC2A1, KCNMA1, ADCY5 and other genes could also lead to PKD phenotypes. Functional imaging studies have found that PKD patients have subtle structural or functional abnormalities in the cortex, basal ganglia and thalamus. This paper reviews the recent advances in genetics and functional imaging of PKD, aiming at helping us to further understand the underlying pathophysiological mechanisms of PKD.

Objective:To evaluate the application value of electroencephalogram (EEG) in diagnosing brain death.Methods:From December 2015 to July 2019, basic profiles, clinical data and ancillary examinations were collected retrospectively for patients applying for brain death determination. Clinical test of brain death had to be performed by at least two qualified physicians. Ancillary examinations included electroencephalogram (EEG), transcranial Doppler ultrasonography (TCD) and short-latency somatosensory evoked potential (SLSEP). The diagnostic criteria were based upon the Chinese Guidelines for Determining Brain Death in Adults and Children.Results:Among a total of 77 patients, 72 of them fulfilled the diagnostic criteria for brain death. The average age was (42±5)(8-67) years and the completion rate of EEG 96.4%. And 13.9% of brain-dead patients demonstrated electromyographic artifact and EEG hinted at electrocerebral inactivity after using muscle relaxants. The diagnostic sensitivity of EEG was 95.8%in brain death. For one false positive case, EEG still predicted the patient's eventual mortality possibly due to the inability of EEG to show electrical activity in brain stem.Conclusions:EEG has an excellent sensitivity in brain death determination. Scalp electromyography artifact is not uncommon on EEG of brain-dead patients. And muscle relaxants may aid the determination process if necessary.