大脑后动脉交通前段及其内穿支研究

本文介绍Willis动脉环后半环大脑后动脉及其内穿支的显微解剖,大脑后动脉交通前段内穿支是脑深部的重要供血血管之一,100％的病例双侧具有该血管。     

Magnetic resonance angiography (MRA) of the circle of Willis: a prospective comparison with conventional angiography in 54 subjects

We prospectively correlated the findings of magnetic resonance angiography (MRA) with those of transfemoral four-vessel angiography in 54 patients to investigate the direction of flow within the circle of Willis. Our primary goal was to assess the direction of flow using the size of the vessel and signal intensity, without saturation techniques. Analysis of the circle of Willis, especially the communicating arteries, was performed double-blind by two groups of two radiologists. Three types of arteries were identified: high flow or cross-cerebral circulation, patent and nonvisualised arteries. Cerebral angiography was the standard for comparison between the two methods. MRA did not reveal any arteries invisible on angiography, thus providing a specificity of 100%. The sensitivity of MRA was 89.2% for the anterior and 81.3% for the posterior communicating arteries, and 100% for the anterior, middle and posterior cerebral arteries. MRA was shown to be a useful technique for the assessment of patency of the circle of Willis.     

Willis环形态与功能对照研究

目的：从不同角度分析Willis环的形态学变异及其功能状况。方法：分别采用脑尸解标本、血管铸型标本及动态血管造影资料进行Willis环的对比分析。结果：正常成人组尸体与活体Willis环分型无差异；活体正常组与活体病理组Willis环的比较有差异；活体正常组与活体病理组PCA供血类型有差异。结论：胎儿与成人、尸体与活体、静态与动态、正常与异常的有机结合能全面评价Willis环的形态学变异及其功能状况，为临床正确诊治脑血管病提供基础依据。     

Circle of Willis atherosclerosis,Alzheimer’s disease and the Dean number

The important role of atherosclerosis in pathophysiology of Alzheimer’s Disease has become evident. Mechanisms such as hyperlipidemia, inflammation, abdominal obesity and insulin resistance are important yet they may not fully explain the specific involvement of the Circle of Willis in these pathologies. The Circle of Wills is a complex geometrical structure which has several areas with different curvature as well as various branching angles of vessels composing the circle. The hemodynamics in this region should take into account the Dean number which indicates the influence of curvature on the resistance to blood flow. Thus, areas with various curvature and angles may have different hemodynamics and there are certain areas in the Circle of Willis that are more likely to develop atherosclerotic changes. Therefore, this could suggest the novel pathophysiological pathway resulting from the geometric peculiarities of the Circle of Willis. One of the directions of future research is to examine whether specific areas of the Circle of Willis are more likely to develop atherosclerotic changes compared to other ones. Selective areas of the Circle of Willis affected by atherosclerotic changes could indicate the primary role of atherosclerosis promoting Alzheimer’s disease although other pathophysiological mechanisms suggesting the opposite direction should be also examined in prospective studies.     

Study of anomalies in the circle of Willis using magnetic resonance angiography in north eastern India

IntroductionThe circle of Willis is a large arterial anastomotic ring present at the basal cistern of the brain, uniting the internal carotid and the vertebrobasilar system. Branches from this arterial ring are distributed to supply the brain. In the year 1664, Sir Thomas Willis was the first to describe the importance of the circle in maintaining collateral flow. It was observed that there is very little mixing of blood between the collateral branches of the circle. These collaterals may however open up during occlusive episodes of the proximal feeding vessels. The anatomy of the circle is known to vary considerably and functionally a complete circle is a rare finding. This type of incomplete or variant forms off the circle may diminish its role as a collateral route.MethodsThe morphological pattern of circle of Willis of 70 healthy individuals from northeast India was studied retrospectively using Time of Flight-Magnetic resonance angiography (TOF-MRA).ResultsOnly 17 (24.28%) MRA's presented with a complete (classic) circle of Willis. Most common variant observed in our study was unilateral hypoplastic posterior communicating artery (20%). Most common variant observed in the anterior circulation was unilateral hypoplastic A1 segment of anterior cerebral artery (11.42%).DiscussionMost of the variant forms observed were comparable with earlier established findings. This variability (rare patterns) can be distinguished from an anomalous architecture if correlated phylogenically and embryologically.     

Prevalence of restless legs syndrome and associated factors in an otherwise healthy population: results from the Danish Blood Donor Study

ObjectiveRestless legs syndrome (RLS) is a neurological sensorimotor disorder characterized by uncomfortable sensations in the legs. RLS often occurs as a comorbid condition. Besides an increased risk of iron deficiency, blood donors are considered to be generally healthy. Blood donors are therefore an ideal population for studying factors associated with RLS occurrence, herein the role of iron. It is suggested that RLS is linked to sex, age, low socioeconomic status, unhealthy lifestyle, and iron deficiency. The objective of this study is therefore to estimate the RLS prevalence and identify associated biological, sociodemographic, economic, and lifestyle factors in a population of blood donors.MethodsA total of 13,448 blood donors enrolled in the Danish Blood Donor Study from May 2015 to May 2016. RLS cases were identified using the validated Cambridge–Hopkins RLS-questionnaire. Logistic regression models were applied to assess the relationship between RLS and data on socially related factors collected using questionnaires and population registers.ResultsIn this study, 7.2% women and 4.5% men were classified with RLS. RLS was associated with: female sex, high age, smoking, frequent alcohol consumption, and low education. RLS-related symptoms were associated with obesity, parity and donation intensity three years prior to inclusion among women. RLS was not related to: reduced plasma ferritin, employment status, and income.ConclusionsRLS is a frequent disorder in otherwise healthy individuals. The associations discovered in this study can be utilized in preventing or reducing RLS symptoms.     

Echocardiographic assessment of left ventricular outflow tract in d-transposition of the great arteries

The left ventricular outflow tract in 38 patients (aged 0.3 to 13 years) with complete d-transposition of the great arteries, 31 with intraatrial (Mustard) repair, was quantitated with echocardiography, and the findings were correlated with hemodynamic and angiographic data. The left ventricular outflow tract (LVO) was measured on the echocardiogram as an anteroposterior dimension between the closure point on the mitral valve below the pulmonary arterial root (PA) and the left endocardial surface of the interventricular septum. This measurement was expressed as an LVO/PA ratio and on the basis of these measurements three groups were recognized.Group I consisted of 14 patients who had an unobstructed left ventricular outflow tract and no significant pressure differences between the pulmonary artery and left ventricle. In Group II, the 16 patients had evidence of dynamic obstruction and mild to moderate pressure differences between the pulmonary artery and left ventricle, characterized in the echocardiogram by LVO/PA ratios comparable with those of Group I, but with an abnormally prominent early posterior systolic septal bulge in the left ventricular outflow tract, abnormal systolic anterior motion of the mitral valve and coarse fluttering of the pulmonary valve. In Group III the eight patients had anatomically fixed stenosis of the left ventricular outflow tract and severe left ventricular outflow pressure gradients characterized in the echocardiogram by a reduced LVO/PA ratio and fine vibrations of the pulmonary valve. Angiographically discrete or long segmental narrowing of the left ventricular outflow tract correlated well with the echocardiographic data. Echocardiographic measurements of left ventricular posterior wall thickness also correlated well with the severity of left ventricular outflow stenosis in these three groups. The echocardiogram provides clinically useful quantitative and qualitative analysis of the left ventricular outflow tract in patients with complete transposition of the great arteries.     

长爪沙鼠脑底血管红油铸型标本制作及其后交通支变异类型分析

目的制备普通级长爪沙鼠脑底血管红油铸型标本,分析其脑部血管分布,为筛选出可稳定制备脑缺血模型的长爪沙鼠品系奠定基础。方法挑选8～10周龄普通级长爪沙鼠和SPF级SD大鼠各20只(雌雄各半),制备脑血管红油铸型标本,取全脑4%福尔马林溶液固定,解剖显微镜下观察拍照。结果运用血管铸型法可有效地制备长爪沙鼠脑底血管红油铸型标本,与SD大鼠比较认为长爪沙鼠脑底血管后交通支存在4种变异类型。结论通过脑底血管红油铸型标本可直观地分析长爪沙鼠脑底血管分布,为建立长爪沙鼠Willis动脉环缺陷明显品系和制备脑缺血动物模型奠定解剖学基础。