Author: Xu Yun
Author's unit: Department of Neurology, Gulou Hospital, Medical College of Nanjing University
Cerebral small vascular disease (csvd) is a kind of syndrome with many clinical symptoms, such as mood abnormality, urination abnormality, gait abnormality, lacunar cerebral infarction, cerebral hemorrhage, cognitive dysfunction, dementia, Parkinson's syndrome and so on. MRI showed white matter injury, also known as high white matter signal (T2WI and FLAIR), lacunar infarction, enlarged perivascular space, cerebral micro hemorrhage and brain atrophy. Csvd by Europe Clinical classification is divided into 6 types: type I, arteriosclerosis, pathological changes of cellulose like necrosis, lipid hyaline degeneration, arteriosclerosis, microartoma, segmental structural disorder or disintegration of arterioles; type II, sporadic or hereditary amyloid angiopathy (CAA); type III, hereditary small angiopathy, such as autosomal dominant inheritance with subcortical infarction and leukoencephalopathy CADASIL, CARASIL with subcortical infarction and leukoencephalopathy, mitochondrial encephalomyopathy with hyperlactatemia and stroke like attack (MELAS), Fabry's disease, hereditary small retinal vascular disease, type IV, inflammatory or immune-mediated small vascular diseases, such as Wegener's granuloma, rheumatism, vasculitis, type V, collagen vein Type VI, other small vascular diseases, such as post radiation small vascular diseases. 80% of them are type I arteriosclerosis, which is closely related to age, that is, aging.
The incidence rate of CSVD related to aging has increased significantly worldwide, and it is more prevalent in people over 60. It has become a major threat to human health. It is the second largest disease in elderly people following Alzheimer's disease, accounting for 25% to 30% of stroke and 45% of Alzheimer's disease. At present, there is a lack of large-scale epidemiological data. The incidence of csvd and lacunar infarction in the West was slightly lower than that in China (19.3% vs 33.1%, 32.2% vs 42.1%). About 72% of the elderly over 60 years old in the United States suffer from different degrees of white matter damage and cerebral microbleeds, and the detection rate in women is higher than that in men. In the elderly over 65 years old, 90% had different degrees of white matter damage, 6% - 20% had lacunar infarction, 5% - 15% had micro hemorrhage.
There is no significant difference between csvd and gender, region and race. The incidence of high white matter signal was about 5% in the 50 year old group, nearly 100% in the 90 year old group, and the incidence of cerebral micro hemorrhage increased from 6.5% in the 45-50 year old group to 36% in the 80-90 year old group.
The risk factors of csvd related to aging were hypertension (blood pressure higher than 140 / 90 mmHg), smoking, diabetes, sleep apnea syndrome, chronic kidney disease, subcortical stroke related branch atherosclerotic disease, hyperlipidemia, etc.
At present, the clinical diagnosis of csvd related to aging mainly depends on MRI (Figure 1). It usually occurs over 50 years old, and can complain of dizziness, gait instability, depression or cognitive decline, etc.; MRI shows at least one of the following signs: high white matter signal (Fazekas score ≥ 2 points), lacunar infarction, enlarged perivascular space, cerebral microbleeding.
Figure 1 common MRI manifestations of cerebrovascular disease
In terms of image quantification, the following methods are often used in clinical practice: ① quantitative method of brain white matter injury, commonly used Fazekas visual assessment scale, is simple and convenient (Figure 2); 3D flair white matter automatic positioning, extraction and quantitative method can be used for clinical research and accurate quantification (Figure 3). ② Micro hemorrhage can be measured by anatomical position scale and peripheral vascular space by visual scale. ③ At present, the total score of MRI can predict the cognitive function, the recurrence of ischemic stroke and the severity of cerebral hemorrhage, which needs more evidence-based medicine verification.
Periventricular: 0 = none; I = thin cap or pencil like lesions; II = smooth halo; III = irregular periventricular white matter with high signal, invading deep white matter. Deep (subcortical): 0 = none; I = punctate lesions; II = lesions begin to fuse; III = lesions large-scale fusion.
Figure 2 Fazekas visual assessment scale of brain white matter injury
Fig. 3 automatic quantitative method of 3D flair white matter
The current problem is that with the increase of age, the image changes of csvd appear in most elderly people, but not all of them will become csvd patients. How to early warn and predict which situation may evolve into csvd? This is an urgent problem in clinical practice. There are many cohort studies and prospective studies at home and abroad, mostly focusing on imaging research, and a small part of them are looking for molecular markers of peripheral blood. There are different deficiencies in these studies, such as few samples, incomplete data or retrospective, often unable to integrate all clinical and various complex examination results, without considering a variety of factors and the nonlinear correlation between multiple factors, so clinical guidance is lack of comprehensive and accurate, and it is difficult to promote. With the popularization and application of big data theory and technology, the above problems can be solved from the multi-modal level.
At present, there is no specific treatment method for csvd. The main clinical treatment methods are: ① main prevention and treatment of vascular risk factors: the control of blood pressure is very important. It has been reported that the control of blood pressure can slow down the brain white matter damage, as well as the occurrence and development of csvd, but there are also reports with poor effect, which need further multi center clinical research; of course, the control of high-risk factors such as blood glucose and blood lipid It's also very important. ② Antiplatelet therapy: This is a difficult problem in clinical practice. For example, a patient with recurrent lacunar cerebral infarction has more cerebral micro hemorrhage, especially when one or more antiplatelet drugs are ineffective, what should be done? The latest research suggests that, compared with the blank control group, single antiplatelet drug can reduce the recurrence rate of lacunar infarction by 22%. Current data do not support the discontinuation of antiplatelet drug therapy in csvd patients with multiple microbleeds, even if they show symptomatic intracranial hemorrhage or cerebral microbleeds on MRI, they also have indications for antiplatelet therapy. It is suggested that under the condition of clinical conditions, combined with platelet function, pharmacogenomics and drug metabolism to help clinical individualized antiplatelet therapy, so as to improve the effectiveness and safety of antiplatelet therapy. ③ In the future, we hope to focus on pathogenesis or pathological changes, such as vascular endothelial damage, blood-brain barrier damage and brain immune inflammation. It has been reported that the use of prostaglandins and other drugs will be helpful. It is hoped that more clinical research and development of related targeted drugs will be carried out in the future.
From Chinese Journal of stroke
Volume 4, April 15, 2020
Chinese Stroke Society annual meeting (CSA) and Tiantan international Cerebrovascular Disease Conference (TISC)