DTI在急性缺血性脑卒中所致皮质脊髓束损伤中的应用研究

目的:利用DTI探讨急性缺血性脑卒中病人大脑白质纤维束各向异性特征和皮质脊髓束受损与肌力的关系。方法:对9例正常被试和9例急性期缺血性脑卒中病人进行常规MR T1WI、T2WI和DTI检查,对数据进行离线后处理,采用dTV.II软件处理,获得FA图及方向编码彩色(DEC)图,并重建双侧皮质脊髓束3D纤维束图。结果:在正常组双侧白质纤维束FA值无明显差异,重建FA值图与方向编码彩色图可显示大部分主要的白质纤维束。在脑卒中病人组梗死区FA值显著低于健侧,两侧相比差异有显著性意义(t=4.570,P<0.001)。病变侧皮质脊髓束受压、变形、移位、部分断裂,皮质脊髓束受累情况与肌力有相关性(rs=0.888,P<0.05)。结论:DTI可显示脑内白质纤维束的走行及分布,为大脑白质纤维束的研究开辟了新的广阔领域。DTI FA值图及DEC图可以显示卒中病人梗死区白质纤维的方向与各向异性程度。3D纤维束图可以更立体直观的显示锥体束状况,有利于探讨皮质脊髓束损伤程度与肌力的关系,对临床及判断预后有重要价值。     

One-year outcome after first-ever stroke according to stroke subtype, severity, risk factors and pre-stroke treatment. A population-based study from Tartu, Estonia

The aim of the current study was to evaluate the outcome at 1 year following a first-ever stroke based on a population-based registry from 2001 to 2003 in Tartu, Estonia. The outcome of first-ever stroke was assessed in 433 patients by stroke risk factors, demographic data and stroke severity at onset using the Barthel Index (BI) score and the modified Rankin Score (mRS) at seventh day, 6 months and 1 year. Female sex, older age, blood glucose value >10 mmol/l on admission and more severe stroke on admission were the best predictors of dependency 1 year following the first-ever stroke. At 1 year, the percentage of functionally dependent patients was 20% and the survival rate was 56%. The use of antihypertensive/antithrombotic medication prior to stroke did not significantly affect the outcome. The survival rate of stroke patients in Tartu is lower compared with other studied populations. The outcome of stroke was mainly determined by the initial severity of stroke and by elevated blood glucose value on admission. Patients with untreated hypertension had more severe stroke and trend for unfavourable outcome compared with those who were on treatment.     

Critical review of treatment trials in hypertension

Summary: Despite numerous deficiencies in some antihypertensive drug treatment trials, and some questionable selections of studies for inclusion in several meta-analyses, undoubtedly such trials have shown treatment benefits from reducing hypertension. Complications that can be corrected or prevented include malignant hypertension, hypertensive heart failure, stroke and coronary artery morbidity. the all-cause mortality has been lowered in several trials. the benefits have been seen in subjects aged over 60 years, in women and men, and in patients with isolated systolic hypertension. the benefits have been achieved using a wide range of drugs, not only with beta-blockers or diuretics. Non-pharmacological means of lowering blood pressure have not been evaluated in relation to morbidity.     

Trends of incidence and mortality rates of stroke from 1983 to 2000 in Hanzhong rural population

Objective: To explore the trends of incidence and mortality rates of stroke in Hanzhong rural population. Methods: Acting as the WHO MONICA project. Results: The incidence rate of stroke was 152. 9/100 000. There was decline trend in male(P <0. 05). The mortality rate of stroke was 115.9/100 000. There was no significant decline trend during 18-year period (P < 0. 05). The incidence and mortality rates of stroke of male were higher than those of female(P<0. 05). The incidence and mortality rates were all increased with age(P <0. 01 ). Conclusion: It must stick to the long- term prevention measures to decrease incidence rate, and improve the condition of medical treatment to reduce the mortality rate in rural population.     

Building a relationship: communications and relationships between staff and stroke patients on a rehabilitation ward

Communications among staff and patients on a stroke rehabilitation ward form the focus of this article, which reports on some aspects of a larger study using a grounded theory approach. Tape-recorded interviews were transcribed and analysed concurrently according to recommendations for the approach. A main theme entitled building a relationship was identified, and this process was found to occur in a context varying from participative at one end of a continuum to hierarchical at the other. Building a relationship was found to be influenced by role, personal qualities and organizational context. Appropriate relationships between role-holders were subject to negotiation, leading to a resulting congruence or incongruence between participants' expectations of each other and their roles. Personal qualities were brought into play in the process, with patients' views of staff and staff views of patients both being influential. Some of these views seemed to parallel what has been described in earlier literature as ‘the sick role’ and the labelling of patients as ‘good’ or ‘bad’. Responses to personal qualities led to nurses ascribing meaning to patients' behaviour in terms of adjustment to their stroke, giving time to them to help them to adjust, and withdrawal and handing over to other staff if this strategy failed. Organizational context also had an influence on building a relationship, with time constraints being identified particularly by nurses, and the need to fit in the most essential aspects of care. Place was also important, in that nurses were confined to the ward as a work location, whereas other therapists and doctors worked in other places and sometimes had the facility to take patients off the ward to concentrate on therapy. The findings are discussed against the background of related literature and the conclusion is drawn that the crucial role of nurses in rehabilitation is not recognized and valued, and that shortages of resources - especially suitably qualified and trained nursing staff- are a negative influence on building the relationships which are vital to successful rehabilitation.     

Motor loss and swallowing difficulty after stroke: frequency, recovery, and prognosis.

Data relating to motor loss and swallowing difficulties in a community sample of 976 patients who suffered an acute stroke have been analysed. About 17% of patients seen within one week had no paralysis; at 6 months 48% of survivors had no paralysis and 9% had severe paralysis. The Motricity Index used to study motor loss related to functional loss and walking ability; it seems to be a simple valid measure of motor loss. Severe paralysis was associated with a high fatality rate, and only 6%-10% of survivors of an initially severe paralysis made a full recovery by 6 months. If severe persisted at 3 weeks, full recovery was not observed. Loss of sitting balance was associated with a poor outcome. Of conscious patients seen within one week, 14% choked on attempting to swallow and a further 28% had abnormal swallowing: this 42% of patients had a high fatality rate.     

Diffusion Weighting by the Trace of the Diffusion Tensor within a Single Scan

The anisotropy of the water diffusion tensor inside brain causes contrast in diffusion images, which depends on the relative orientation of the diffusion gradients and the subject. Because the trace of a tensor is invariant upon rotation, measurement of this trace can reduce the orientation effect. A family of imaging pulse sequences is presented in which the signal intensity is weighted by the trace of the diffusion tensor in a single scan. The methods are demonstrated for chicken gizzard in several orientations with respect to the gradient frame of reference, and for ischemic injury in cat brain after middle cerebral artery occlusion. The sensitivity of the techniques to the presence of background gradients is measured and discussed in detail. As a result, pulse sequences are suggested that provide reliable diffusion constants in both homogeneous and inhomogeneous magnetic fields. The efficiency of the techniques for clinical application is also evaluated.     

Giant fusiform aneurysm of the vertebro-basilar artery presenting with stroke

The authors describe a case of giant fusiform aneurysm of the basilar artery presenting with ischemic symptoms. Angiography and CT revealed vertebro-basilar fusiform aneurysmal dilatation. Fusiform vertebro-basilar ancurysm is associated with various complications particularly brain stem infarction. Similar lesions in the literature are reviewed and the relationship between this clinical entity and cerebral ischemia, particularly brainstem infarction are discussed.     

Ischemic stroke in infancy,childhood, and adolescence

The authors studied 34 patients with juvenile ischemic cerebrovascular disease over a 15-year period. Of the 34 patients, 23 had intracranial occlusions attributed to cerebral thrombosis or embolism and 11 had occlusions resulting from moyamoya disease. Clinicopathological features were evaluated in the 23 cases with ischemic stroke, but not those with moyamoya disease. The cause of the arterial occlusion remained undetermined in 11 patients and was found to be an embolism based on congenital heart disease in 8, on trauma in 3, and on infection in 1. Cerebral angiography was performed in 21 patients. Of these, 17 had stenoses or occlusions corresponding to their symptoms. CT scans were performed in 10 patients; the lesion in question showed no stenosis or occlusion with cerebral angiography. With regard to prognosis, patients with unknown etiology had good outcomes compared with those with congenital heart disease. With respect to acute infantile hemiplegia, 10 patients had convulsive seizures and 4 had a history of an earlier infection. Angiography and CT scans in patients with congenital heart disease demonstrated arterial occlusive sites in the middle cerebral artery region. Three patients had abscesses after their ischemic lesions.     

肢体远隔缺血期适应联合后适应促进大鼠缺血性脑卒中模型神经发生的作用及机制

目的 探讨肢体远隔缺血期适应(per-conditioning,PerC)联合后适应(post-conditioning,PostC)对缺血性脑卒中后神经再生的作用,并明确PerC联合PostC对脂肪酸β-氧化(fatty acid β-oxidation,FAO)限速酶——肉毒碱棕榈酰转移酶(carnitine palmitoyl transferase 1A,CPT1A)的影响。方法 对成年雄性SD大鼠进行大脑中动脉闭塞(middle cerebral artery occlusion,MCAO)造模,MCAO模型后30 min进行肢体远隔缺血期适应治疗(PerC),再灌注24 h后重复进行肢体远隔缺血适应(PostC),1次/d,直到取材。再灌注14 d后对大鼠进行神经功能评分,通过免疫组织化学染色检测室管膜下区(subependymal ventricular zone, SVZ)神经再生情况,通过酶联免疫吸附测定(enzyme linked immunosorbent assay,ELISA)法检测CPT1A的表达。结果 与MCAO组及PerC/PostC组比较,PerC+PostC组大鼠,身体不对称运动行为评分降低,神经干细胞的数量以及向梗死区迁移的细胞数量增加。Pearson相关性分析显示,神经干细胞的数量与神经功能呈负相关(r=-0.917 9, P<0.0001)。然而,迁移到基底节区的神经干细胞的凋亡数量在各组之间差异无统计学意义。机制研究显示,PerC+PostC组CPT1A的蛋白水平显著增加。结论 PerC联合PostC治疗能够通过增加神经干细胞的数量改善神经功能,神经干细胞的脂肪酸氧化可能是其促进神经干细胞迁移的机制之一。