Redefining periodic patterns on electroencephalograms of patients with sporadic Creutzfeldt-Jakob disease.

OBJECTIVE: We aimed to redefine various periodic patterns (PPs) observed on electroencephalography (EEG) in patients with sporadic Creutzfeldt-Jakob disease (sCJD) using the American Clinical Neurophysiology Society's (ACNS) Criteria. METHODS: We analyzed EEG data of 23 patients with sCJD were admitted to two university hospitals between August 2005 and September 2015. RESULTS: We classified PPs on EEG data into three types: irregular periodic discharges (PDs) with superimposed rhythmic activities, appearing at a median of 8weeks after onset (w.a.o.); rhythmic sharp-and-wave, at a median of 11w.a.o.; and PDs with biphasic or triphasic morphology, at a median of 17w.a.o. Of 16 patients presenting with PPs, 14 had widespread lesions in both cortical and subcortical areas with clinical stage III at admission, and shorter time intervals for admission to hospital from disease onset than patients without PPs (Patients with PP, 11.6±12.2weeks; without PP, 18.2±8.3weeks; p=0.033). CONCLUSIONS: PPs largely presented as three types at different stages of disease progression, and patients who had PPs had more wide spread lesions and rapid disease progression. SIGNIFICANCE: Our redefinition of PPs demonstrated on EEG using the ACNS criteria may contribute to further understanding of the pathological mechanisms of sCJD, and PPs might be a predictive factor of a rapid sCJD progression.

The Effect of Pulsatility Index on Infarct Volume in Acute Lacunar Stroke.

PURPOSE: Lacunar stroke, in the context of small vessel disease, is a type of cerebral infarction caused by occlusion of a penetrating artery. Pulsatility index (PI) is an easily measurable parameter in Transcranial Doppler ultrasound (TCD) study. PI reflects distal cerebral vascular resistance and has been interpreted as a surrogate marker of small vessel disease. We hypothesized that an increased PI, a marker of small vessel disease, might be associated with a larger infarct volume in acute lacunar stroke. MATERIALS AND METHODS: This study included 64 patients with acute lacunar stroke who underwent TCD and brain MRI. We evaluated the association between the mean PI value of bilateral middle cerebral arteries and infarct volume on diffusion-weighted MRI using univariate and multivariate linear regression. RESULTS: The mean infarct volume and PI were 482.18±406.40 mm³ and 0.86±0.18, respectively. On univariate linear regression, there was a significant positive association between PI and infarct volume (p=0.001). In the multivariate model, a single standard deviation increase of PI (per 0.18) was associated with an increase of 139.05 mm³ in infarct volume (95% confidence interval, 21.25 to 256.85; p=0.022). CONCLUSION: We demonstrated that PI was an independent determinant of infarct volume in acute lacunar stroke. The PI value measured in acute stroke may be a surrogate marker of the extent of ischemic injury.