无症状性颈内动脉重度狭窄患者支架置入术与药物治疗的对比研究

目的探讨颈动脉支架置入术与药物治疗对无症状性重度颈内动脉狭窄患者认知功能及脑血流灌注的影响。方法前瞻性连续纳入2013年12月至2015年6月解放军第三○六医院神经内科(120例)及首都医科大学宣武医院神经外科(80例)收治的无症状性单侧重度颈内动脉狭窄患者200例(单侧狭窄率≥70%,对侧狭窄率30%),利用SPSS 17.0统计软件中随机数生成器将患者随机分为支架+药物组及单纯药物组,各100例。所有患者分别于入院时(治疗前)及随访1年后行头部MRI、头颈部CT灌注成像检查及蒙特利尔认知评估量表(Mo CA)评分,并通过CT灌注成像计算出相对脑血流量(r CBF)、相对脑血容量(r CBV)、相对平均通过时间(r MTT)及相对达峰时间(r TTP),比较两组患者认知功能及脑灌注参数的变化,并对认知功能与脑灌注参数的相关性进行分析。结果 (1)最终纳入197例(1例患者死于肺癌,另2例患者电话失访),1年后复查头部MRI,两组患者均未发生缺血性卒中。(2)入院时及随访1年后Mo CA评分,单纯药物组分别为(22.2±3.4)、(22.2±3.4)分,支架+药物组分别为(22.0±3.3)、(24.9±2.8)分,随访1年,支架+药物组患者认知障碍改善程度高于单纯药物组,差异有统计学意义(F=310.760,P0.01)。(3)随访1年,支架+药物组与单纯药物组的r CBV及r CBF均无改善,组间差异均无统计学意义(均P0.05)。入院时及随访1年后,单纯药物组r MTT分别为(1.25±0.11)、(1.27±0.14),支架+药物组r MTT分别为(1.27±0.16)、(1.08±0.07);单纯药物组r TTP分别为(1.35±0.23)、(1.36±0.24),支架+药物组r TTP分别为(1.35±0.20)、(1.07±0.04)。支架+药物组r MTT及r TTP的改善优于单纯药物组,组间差异均有统计学意义(F值分别为207.541及156.151,均P0.01)。(4)支架+药物组治疗前后Mo CA评分的改善与r MTT及r TTP存在负相关关系(r值分别为-0.961及-0.735,均P0.01)。结论单侧无症状性颈内动脉重度狭窄患者存在认知功能减退,颈动脉支架置入术联合药物治疗比单纯药物治疗更有利于通过改善脑血流灌注而提高认知功能。     

Utility of Tissue Similarity Maps Based on Relative Cerebral Blood Volume for Grading Gliomas as Validated by Histological Results

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Non-invasive quantitative pulmonary V/Q imaging using Fourier decomposition MRI at 1.5T

ObjectivesTechniques for quantitative pulmonary perfusion and ventilation using the Fourier Decomposition method were recently demonstrated. We combine these two techniques and show that ventilation-perfusion (V/Q) imaging is possible using only a single MR acquisition of less than thirty seconds.MethodsThe Fourier Decomposition method is used in combination with two quantification techniques, which extract baselines from within the images themselves and thus allows quantification. For the perfusion, a region assumed to consist of 100% blood is utilized, while for the ventilation the zero-frequency component is used. V/Q-imaging is then done by dividing the quantified ventilation map with the quantified perfusion map. The techniques were used on ten healthy volunteers and fifteen patients diagnosed with lung cancer.ResultsA mean V/Q-ratio of 1.15±0.22 was found for the healthy volunteers and a mean V/Q-ratio of 1.93±0.83 for the non-afflicted lung in the patients. Mean V/Q-ratio in the afflicted (tumor-bearing) lung was found to be 1.61±1.06. Functional defects were clearly visible in many of the patient images, but 5 of 15 patient images had to be excluded due to artifacts or low SNR, indicating a lack of robustness.ConclusionNon-invasive, quantitative V/Q-imaging is possible using Fourier Decomposition MRI. The method requires only a single acquisition of less than 30 seconds, but robustness in patients remains an issue.     

Management of Neonatal Hypotension and Shock

The current standard approach to manage circulatory insufficiency is inappropriately simple and clear: respond to low blood pressure to achieve higher values. However, the evidence for this is limited affecting all steps within the process: assessment, decision making, therapeutic options, and treatment effects. We have to overcome the ‘one size fits all’ approach and respect the dynamic physiologic transition from fetal to neonatal life in the context of complex underlying conditions. Caregivers need to individualize their approaches to individual circumstances. This paper will review various clinical scenarios, including managing transitional low blood pressure, to circulatory impairment involving different pathologies such as hypoxia-ischemia and sepsis. We will highlight the current evidence and set potential goals for future development in these areas. We hope to encourage caregivers to question the current standards and to support urgently needed research in this overlooked but crucial field of neonatal intensive care.     

Ischémie reperfusion en transplantation rénale

Ischemia-reperfusion injury is an inescapable phenomenon in kidney transplantation. It combines lesional processes of biochemical origin associated with oxydative stress and of immunological origin in connection with the recruitment and activation of innate immunity cells. Histological lesions associate acute tubular necrosis and interstitial œdema, which can progress to interstitial fibrosis. The extent of these lesions depends on donor characteristics (age, expanded criteria donor, etc.) and cold ischemia time. In the short term, ischemia-reperfusion results in delayed recovery of graft function. Cold ischemia time also impacts long-term graft survival. Preclinical models, such as murine and porcine models, have furthered understanding of the pathophysiological mechanisms of ischemia-reperfusion injury. Due to its renal anatomical proximity to humans, the porcine model is relevant to assessment of the molecules administered to a donor or recipient, and also of additives to preservation solutions. Different donor resuscitation and graft perfusion strategies can be studied. In humans, prevention of ischemia-reperfusion injury is a research subject as concerns donor conditioning, additive molecules in preservation solutions, graft reperfusion modalities and choice of the molecules administered to the recipient. Pending significant advances in research, the goal is to achieve the shortest possible cold ischemia time.     

Superior vena cava flow: Role,assessment and controversies in the management of perinatal perfusion

The superior vena cava (SVC) is a large vein responsible for the venous return of blood from structures located superior to the diaphragm. The flow in the SVC can be assessed with Doppler ultrasound and can be used as a proxy for cerebral perfusion. Early clinical research studies showed that low SVC flow, particularly if for a prolonged period, was associated with short term morbidity such as intraventricular hemorrhage, mortality, and poorer neurodevelopmental outcomes. However, these findings have not been consistently reported in more recent studies, and the role of SVC flow in early management and as a predictor of poor long-term neurodevelopment has been questioned. This paper provides an overview of SVC assessment, the expected range of findings, and reviews the role of SVC flow as a diagnostic and monitoring tool for the assessment of perinatal perfusion.     

Microvascular heart involvement in systemic autoimmune diseases: The purinergic pathway and therapeutic insights from the biology of the diseases

Heart involvement – often asymptomatic – is largely underestimated in patients with systemic autoimmune diseases (SADs). Cardiovascular events are more frequent in patients with SADs compared to the general population, owing to the consequences of inflammation and autoimmunity and to the high prevalence of traditional risk factors. Coronary microvascular disease (CMD) is a form of cardiac involvement that is increasingly recognised yet still largely neglected. CMD, the incapacity of the coronary microvascular tree to dilate when myocardial oxygen demand increases or when there is a microvascular spasm (or subclinical myocarditis), is increasingly reported because of the widespread use of new cardiac imaging tools, even in a subclinical phase. The assessment of myocardial coronary flow reserve (CFR) emerged as the most effective clinical tool to detect microvascular damage. The potential causes of microvascular damage, molecular and cellular inflammation along with a pathological CD39-CD73 axis, need always to be considered because data show that they play a role in the occurrence of acute coronary syndromes, heart failure and arrhythmias, even in the early asymptomatic stage. Data suggest that controlling disease activity by means of methotrexate, biologic drugs, antimalarial medications, statins and aspirin, according to indication, might reduce the cardiovascular risk related to macrovascular and microvascular damage in most patients with SADs, provided that they are used early and timely to control diseases. The need of new biomarkers and a careful assessment of myocardial CFR emerged as the most effective clinical tool to detect microvascular damage.