组织多普勒判别方程法定量检测冠心病人存活心肌

目的 探讨DTI(多普勒组织显像技术)结合DSE(超声多巴酚丁胺负荷试验)建立判别方程定量检测存活心肌的可能性.方法 37 例研究对象,均按常规行定量冠状动脉造影(QCA)检查,其中 25 例确诊为冠心痛(CAD),将25例 CAD 患者随机分为CAD1组15例和CAD2组10例,12例为QCA阴性的正常人作为对照组(CON组);三组间年龄、性别、体重指数等均无统计学差异(P＞0.05).其中CON组和CADl组采用标准的DSE方案(0～40μg/kg·min),CAD2组采用标准DSE方案与异舒吉合用;使用DTI技术,分别于静息状态、小剂量(10 μg/kg·min)及峰值剂量时观察左室16个节段心肌运动速度的变化,记录各室壁节段的收缩期(S)、舒张早期(E)及舒张晚期(A)的峰值速度V、加速时间AT、减速时间DT和时间速度积分VTI,以＆V≥35%为判定存活心肌的标准,建立判别方程.结果 所建立的判别方程CON组错判CAD1和CAD2组的比例是16.67%;CAD1组错判CON组的比例为12.50%;CAD2组错判CON组的比例为11.11%.结论 组织多普勒判别方程法可以精确定量地检测存活心肌,为DSE开辟了一条新途径.     

大鼠C6脑胶质瘤模型的病理及磁共振成像特征

目的:探讨正常大鼠及大鼠脑胶质瘤模型的磁共振成像(MRI)特征.方法:将28只Wistar大鼠经右侧冠状缝距中线4 mm处缓慢进针注入C6胶质瘤细胞株悬液,按术后3、7、10、14、17、21 d及自然死亡顺序采集肿瘤标本,行病理检查并观察肿瘤生长方式;再随机选取5只大鼠脑胶质瘤模型按接种后8、11、14、17、21及24 d行常规平扫及增强扫描,观察注射对比剂后0、10、20、30、40及50 min轴位及冠状位T1WI扫描;选取2只正常大鼠行MRI T1WI、T2WI平扫和增强扫描.结果:正常大鼠脑组织T1WI呈稍长T1信号,皮质与白质分界不清;T2WI脑皮质与白质能较好分辨,皮质信号高于白质,双侧侧脑室后角呈高信号,小脑幕呈对称低信号;增强扫描脑组织无强化.大鼠脑胶质瘤模型从接种8～24 d均可见接种部位头皮软组织增厚,呈等T1、长T2信号;第14天右侧大脑半球接种点可见小点状稍长T2信号,增强扫描呈小点状强化;第17天病变更明显,呈小结节状强化;第21天结节较前增大,强化更为明显;至第24天病变进一步增大,右侧大脑半球1/3～1/2呈长T2信号,但T1WI病变始终与周围正常脑组织不能区分;动态增强扫描病变区呈明显结节状强化,周围水肿区无强化;接种部位增厚头皮软组织始终呈明显强化.结论:正常大鼠脑灰、白质及脑室在T2WI能较好显示,小脑幕呈对称长T1、短T2信号,增强扫描正常脑组织无强化.大鼠C6脑胶质瘤呈等T1、长T2信号,T2WI及增强扫描均能检测出大鼠C6脑胶质瘤病灶,增强扫描更能准确反映病变大小及形态.     

腹腔多发性脂肪瘤7例分析

目的:探讨腹腔多发性脂肪瘤的临床特点.方法:对1992年2月～2004年10月7例腹腔多发性脂肪瘤行13次手术治疗进行回顾性分析.结果:无手术死亡,7例术后均复发,随着手术次数增多,病理恶性程度也随着递增,复发时间缩短.结论:腹腔多发性脂肪瘤以手术治疗为主,复发后病理性质改变,积极手术治疗,仍可提高生活质量,延长生命.     

71例腹主动脉瘤的基线CT特征与病变进展的相关性

目的 评估与腹主动脉瘤(AAA)进展相关的基线CT特征,为AAA的临床治疗路径提供参考。方法 选取2012年1月至2021年12月至少行两次增强CT扫描的83例AAA患者的临床及影像资料进行分析,两次扫描间隔3个月以上。测量瘤体的直径、面积、长度、曲度、血栓面积等基线CT特征,并根据瘤体直径计算AAA的年进展速度。将有进展的AAA分为缓慢进展组(进展速度≤0.25 cm/y)和快速进展组(进展速度>0.25 cm/y)。采用独立样本t检验或Mann-Whitney U非参数检验进行组间比较;运用单变量与多变量线性回归分析,确定与AAA进展有关的基线CT特征。结果 71例患者存在病变进展,其中缓慢进展组35例,快速进展组36例。快速进展组的基线瘤体长度显著大于缓慢进展组(P=0.03)。多因素相关性分析结果显示,瘤体面积(β=0.048,P=0.020)、长度(β=0.051,P=0.007)与进展速度呈独立正相关,瘤体曲度(β=-0.005,P=0.034)、血栓面积(β=-0.034,P=0.013)与进展速度呈独立负相关。结论 AAA患者基线CT特征中瘤体面积、长度、曲度、血...     

高频超声在军事训练伤诊疗中的应用进展

军事训练伤（military training injury,MTI）是军队官兵由于军事训练而造成的训练损伤,是现阶段全球部队官兵常见的训练损伤类型。军事训练伤严重影响训练效率、职业健康和整体军事准备状态,是长期困扰部队官兵健康的难题。近年来,高频超声飞速发展,对肌骨疾病的诊断优势日益凸显。高频超声越来越多的应用于军事训练伤的诊断和治疗。本文就高频超声在军事训练伤诊疗中的应用进展作综述,为我军官兵训练伤防治提供借鉴。     

Imaging update on soft tissue sarcoma

Soft tissue sarcomas (STS) are rare tumours presenting as soft tissue lumps. Ultrasound is often the primary modality for the initial assessment, with MRI the mainstay for lesion characterisation. PET/CT along with other emerging MRI sequences are used in certain situations as an adjunct and problem solving tool in STS staging and assessment of disease recurrence. Recent advances include the promise of whole body MRI, hybrid PET/MRI, diffusion weighted imaging, dynamic contrast enhanced MRI and advances in artificial intelligence. This article discusses current concepts in extremity STS imaging and highlights recent advances.     

A multivariate hypothesis testing framework for tissue clustering and classification of DTI data

The primary aim of this work is to propose and investigate the effectiveness of a novel unsupervised tissue clustering and classification algorithm for diffusion tensor MRI (DTI) data. The proposed algorithm utilizes information about the degree of homogeneity of the distribution of diffusion tensors within voxels. We adapt frameworks proposed by Hext and Snedecor, where the null hypothesis of diffusion tensors belonging to the same distribution is assessed by an F‐test. Tissue type is classified according to one of the four possible diffusion models, the assignment of which is determined by a parsimonious model selection framework based on Schwarz Criterion. Both numerical phantoms and diffusion‐weighted imaging (DWI) data obtained from excised rat and pig spinal cords are used to test and validate these tissue clustering and classification approaches. The unsupervised clustering method effectively identifies distinct regions of interest (ROIs) in phantoms and real experimental DTI data. Copyright © 2009 John Wiley & Sons, Ltd.     

Preparation and characterization of Antheraea assama silk fibroin based novel non‐woven scaffold for tissue engineering applications

The quest for novel materials as scaffolds with suitable micro‐architecture for supporting tissue neogenesis in tissue engineering and regenerative medicine (TERM) is continuing. In this paper we report an Antheraea assama silk‐based non‐woven fibroin scaffold for applications in TERM. The novel three‐dimensional scaffold is highly interconnected and porous, with a pore size of 150 µm, porosity of 90% and water uptake capacity of 85%. FTIR revealed a typical β‐sheet structure of fibroin. The scaffold has thermal and mechanical properties superior to those of Bombyx mori, as revealed by DSC, TGA and tensile tests. The scaffold exhibited satisfactory blood compatibility, as determined by thrombogenicity, haemolysis, platelet/leukocyte count, platelet adhesion and protein adsorption studies. The scaffold was found to be cytocompatible with human cell lines A549, KB, HepG2 and HeLa for a period of up to 4 weeks. SEM analysis revealed excellent attachment, spreading and migration of cells in the scaffold. MTT assay was performed to estimate the viability and growth of cells in the matrix. Quantification of collagen in cell–scaffold constructs was done by picro‐Sirius red assay. Ex ovo chorioallantoic membrane assay and nitric oxide estimations in spent culture medium showed the scaffold's ability to promote angiogenesis. Finally, the biodegradability of the scaffold was determined by the weight loss observed upon treatment with trypsin over a period of 4 weeks. The results reveal that the fibroin from A. assama is a promising candidate as a biocompatible, biomimetic and biodegradable biomaterial of natural origin for applications in TERM. Copyright © 2009 John Wiley & Sons, Ltd.