A large-scale population survey has been made to clarify the degree of harm and feature of distribution of cerebrovascular disease (CVD) in China. The sample investigated was 5814851 from about a billion people in 29 provinces, municipal cities and autonomous regions except Taiwan in China. The incidence, prevalence and mortality rates have been standardized by the direct method using the world standard population. It has been found that the incidence rate of CVD in China was 109.95 per 100 000 people in 1986 and its 95%CI (confidence interval) was 107. 25 ~ 112. 65 per 100000. The age-standardized incidence rate was 115.87/100000. The point prevalence rate of CVD in China was 245.49 per 100000 people on December 31, 1986 and its 95%CI was 241.57-249.61 per 100000, with an age-standardized prevalence rate of 259.86 per 100000. The mortality rate of CVD was 76.78 per 100000 in 1986 and its 95%CI 74.52~79.04 per 100000, with an age-standardized mortality rate of 80.94 per 100000. It has also been found that there was a tendency for the rates to increase gradually from south to north and to decrease progressively from east to west. The models of linear regression have been established between latitude and rates as well as between longitude and rates, respectively. The incidence, prevalence and mortality rates of CVD differ significantly in various topographic areas. They were much higher in cities than in rural areas, and much higher in men than in women. The incidence, prevalence and mortality rates increased with the age, and their relationships were fitted with logistic curve, respectively.

Point prevalence rate of complete stroke on December 31, 1986 in China was investigated using a retrospecive section study for 5 814 851 people of 29 provinces and cities (excluding Taiwan province), and 14275 stroke cases were found. Point prevalence rate was 245.49 per 100000 people with 95% CI (confidence interval) 241.57-249.61 per 100000 people. The rate standardized by the constituent ratio of population between city and rural area of China in 1986 was 247.66 per 100000 people. The rate age-standardized by the population of China in 1982 accounted for 191.92 per 100000 and the rate agestandardized by the world standard population was 259.86 per 100000 people.It has also been found that there was a tendency for the prevalence rates to increase gradually from south to north and to decrease progressively from east to west. The linear regression models have been fitted between the point prevalence rates and latitude or longitude respectively. The results were Y= 12.3819?-1107.38 (tb = 4.65 df = 5 P = 0.0056) for longitudes and Y = 12.6279?-146.6266 (tb = 11.7517 df = 4 P = 0.0003) for latitudes. There was a difference statistically among various topographic areas. The prevalence rate was much higher in urban areas than rural areas and much higher in men than in women. The prevalence rate increased with age and their relationships have been fitted well with the logistic curve.

Stereo-electroencephalography (SEEG) is widely used to record the electrical activity of patients' brain in clinical. The SEEG-based epileptogenic network can better describe the origin and the spreading of seizures, which makes it an important measure to localize epileptogenic zone (EZ). SEEG data from six patients with refractory epilepsy are used in this study. Five of them are with temporal lobe epilepsy, and the other is with extratemporal lobe epilepsy. The node outflow (out-degree) and inflow (in-degree) of information are calculated in each node of epileptic network, and the overlay between selected nodes and resected nodes is analyzed. In this study, SEEG data is transformed to bipolar montage, and then the epileptic network is established by using independent effective coherence (iCoh) method. The SEEG segments at onset, middle and termination of seizures in Delta, Theta, Alpha, Beta, and Gamma rhythms are used respectively. Finally, the K-means clustering algorithm is applied on the node values of out-degree and in-degree respectively. The nodes in the cluster with high value are compared with the resected regions. The final results show that the accuracy of selected nodes in resected region in the Delta, Alpha and Beta rhythm are 0.90, 0.88 and 0.89 based on out-degree values in temporal lobe epilepsy patients respectively, while the in-degree values cannot differentiate them. In contrast, the out-degree values are higher outside the temporal lobe in the patient with extratemporal lobe epilepsy. Based on the out-degree feature in low-frequency epileptic network, this study provides a potential quantitative measure for identifying patients with temporal lobe epilepsy in clinical.
Brain Waves ; Electroencephalography ; Epilepsy, Temporal Lobe ; diagnosis ; Humans