二维应变对左心室整体应变与应变率的研究

目的评价新的超声软件二维应变（2DS）用于定量左心室整体应变与应变率的可行性与价值.方法采集21例心衰患者与15例正常对照者心尖二腔、三腔、四腔长轴与乳头肌水平短轴二维灰阶动态图.采用心尖双平面Simpson法测量左室射血分数（EF）.应用2DS软件由心尖长轴图像测量左室长轴收缩峰值应变（GSL）与应变率（GSrL）;乳头肌短轴图像测量左室轴向收缩峰值应变（GSC）与应变率（GSrC）.比较心衰组与对照组各参数测值,分析EF与应变及应变率参数相关性.结果心衰组GSL、GSrL、GSC及GSrC均显著低于正常组（P〈0.001）.EF与GSL、GSrL、GSC及GSrC均有良好的相关性（r=0.88,0.87,0.85,0.83）.结论 2DS可用于定量左室整体应变与应变率,有望成为客观准确定量左室功能的新方法用于临床.     

心肌应变与应变率在心血管疾病中的应用

近年来我国心血管疾病的发病率以及死亡率逐年增多,现已成为我国最高致死性疾病之一,对此类患者局部心肌功能的评价对其疾病的诊断、治疗及预后具有重要意义,因此在临床工作中,迫切需要一个能对局部心肌功能做出客观、定量评价的技术。心肌应变(Strain,S)及应变率(StrainSRate,SR)可以测量局部心肌组织发生的极小形变,从而更加准确的评价局部心肌功能及室壁运动。本文将就近年来心肌应变与应变率在心血管疾病中的应用情况进行综述。     

系统性红斑狼疮患者左心功能的应变和应变率研究

目的 探讨应变和应变率显像评价系统性红斑狼疮(SLE)患者左心功能的临床应用价值.方法 60例正常人与62例SLE患者均接受常规超声及组织多普勒检测,获取二尖瓣血流E/A值、左室短轴缩短率(LVFS)、左室射血分数(LVEF)及左室心肌的收缩期及舒张期峰值应变和应变率.结果 ①SLE组和正常对照组E/A值、LVFS及LVEF无明显差异(P＞0.05);SLE组心肌的收缩期应变、应变率峰值低于正常对照组,但差异无统计学意义(P＞0.05).②SLE组舒张期应变率峰值低于正常对照组且差异有统计学意义(P＜0.01).③SLE组抗心肌抗体(AHA)阳性者心肌舒张期应变率峰值低于AHA阴性者(P＜0.05).结论 应变及应变率与AHA结合可以敏感检测SLE患者左心功能的早期损害.     

正常人心肌应变及应变率定量分析

目的 定量研究我国成年人心肌应变及应变率的正常值范围、心肌各节段之间的差异，以及与年龄和性别的关系。方法 应用GE Vivid 7超声仪及Q-analyze软件对50例健康者左右心室心肌各节段进行应变和应变率定量分析。结果 左室基底段、中间段和心尖段的应变和应变率依次递减，基底段最大，心尖段最小。左室基底段室间隔、前壁、后壁、下壁和侧壁的应变和应变率差异无显著性意义。右室中间段的应变和应变率最大，右室基底段的应变大于左室，右室中间段和心尖段的应变和应变率测量值均明显大于左室，性别和年龄对左右心室肌应变和应变率的影响不大。结论 应变或应变率成像能够定量分析局部心肌的变形，为临床评价心功能提供了又一有效工具。     

应变和应变率成像结合冷加压试验对健康成年人肱动脉应变及应变率储备的初步研究

目的 探讨应变和应变率成像结合冷加压试验评价健康成年人肱动脉应变及应变率储备的可行性及其临床意义.方法 应用应变和应变率成像技术获得108例健康成年人冷加压试验前后的肱动脉的最大径向应变和应变率,计算径向应变和应变率储备.结果 108例健康成年人肱动脉的最大径向应变和应变率在冷加压试验前后差异有统计学意义(P<0.05),应变储备的参考范围为(25.26±6.35)%,应变率储备的参考范围为(30.06±7.57)%.结论 应变和应变率成像能够定量评价正常成年人肱动脉的最大径向应变和应变率,还可通过冷加压试验获得健康成年人肱动脉的应变和应变率储备.     

Hydroxyapatite-coated strain gauges for long-term in vivo bone strain measurements.

The aim of this study was to examine the bonding process between hydroxyapatite-coated strain gauges and bone in order to continue development of a long term in vivo strain measurement device. Two types of commercially available hydroxyapatite (HA) particles were applied to the sensing surface of uniaxial strain gauges using a polysulfone solution as an adhesive. Characterization by scanning electron microscopy and x-ray diffraction (XRD) was used to determine materials property differences between the two powders. Interfacial strengths between the HA coatings and the strain gauges were tested and found comparable to interfacial strength obtained by a plasma sprayed HA coating on the surface of a titanium implant. Gauges were surgically placed on the periosteal surface of greyhound femora. Three groups of dogs were implanted with gauges for periods of 3, 6, and 12 weeks using cyanoacrylate, resorbable sutures, and cable ties to initially hold the gauge against the surface of the bone. Following euthanasia, the femora of the dogs were explanted and subjected to cantilever loading. Response of the implanted HA-coated gauges were compared to a control set that had been freshly glued onto the contralateral femur. Full response, that is, 100% of the strain measurement with respect to the control, was obtained after 12 weeks in vivo. Attachment of HA-coated gauges with circumferential suture showed bonding, while HA-coated gauges attached with cyanoacrylate did not bond to bone. After mechanical testing, femora were embedded in polymethylmethacrylate, cut, ground, and polished. Sections were stained using mineralized bone stain (MIBS) and optical microscopy was performed using transmitted and fluorescent light to allow analysis of remodeling occurring in the region of the strain gauges. Bone formation occurred at the HA surface of sutured gauges, and a fibrous tissue layer developed between the bone and HA coating when the tissue adhesive was used to initially bond the gauge. Fluorescence microscopy indicated an increase in the number of areas of bone remodeling adjacent to the gauge but a normal rate of remodeling of 0.93 +/- 0.07 mum/day was observed. No gross bone remodeling due to strain gauge placement was observed. Backscattered electron imaging (BSE) indicated new bone apposition at all time periods.     

Auto strain ratio system for the quality control of breast strain elastography

Purpose

To determine the reproducibility, accuracy, and quantitative values of the auto strain ratio system (ASRS)—a newly developed strain elastography-based program.

Materials and methods

First, the accuracy of ASRS was verified using a breast phantom. A prospective clinical study was then performed in patients. Two hundred and one women (mean age 52.4 years ± SD 14.5) with 232 breast lesions (177 benign and 55 malignant) were enrolled in this study. We assessed the correlation between ASRS and manual strain ratio (MSR), calculating the diagnostic performance to determine the cut-off. The area under the receiver operating characteristic curve (AUC) was calculated.

Results

ASRS was strongly correlated with the subtle differences in phantom stiffness (R = 0.87). In the clinical study, there was a significant correlation between MSR and ASRS with R = 0.79 (P < 0.001). ASRS (cut-off = 3.9) had a sensitivity of 81.8%, specificity of 88.7%, accuracy of 87.1%, positive predictive value of 69.2%, and negative predictive value of 94%. The AUC of ASRS was 0.89.

Conclusion

The findings from this study have demonstrated that it is possible to quantify strain elastography and control its accuracy. ASRS is expected to contribute to the standardization of breast elastography.

     

应变及应变率显像评价尿毒症性心肌病的心功能

目的探讨应变及应变率显像评价尿毒症性心肌病（尿毒症组）心功能的价值。方法应用应变、应变率显像、组织多普勒显像测量35例尿毒症性心肌病与30例正常人（对照组）左室各节段的应变（ε,包括εS和εE）、应变率（SR,包括SRS和SRE）,室壁运动峰值流速（V,包括VS和VE）。结果尿毒症组的εS、SRS、SRE、VS、VE明显低于对照组（t分别=2.45、2.09、5.31、4.26、4.63,P均〈0.05）;②εS、SRS、SRE和VS、VE呈直线正相关（t分别=4.78、5.63、5.05和4.31、4.91、5.05,P均〈0.05）;③εS、SRS、SRE评价心功能受损的敏性和特异性均高于参数VS（t分别=2.05、2.14、2.74和2.17、2.07、2.69,P均〈0.05）,SRS、SRE评价心功能受损的敏感性和特异性也均高于参数VE（t分别=2.08、2.15和2.11、2.07,P均〈0.05）。结论应变、应变率显像能较好地评价心肌局部收缩功能,对早期诊断尿毒症心肌病有较好价值,为临床综合治疗提供理论依据。     

应变及应变率成像技术评价左心房功能的研究进展

左心房功能在预测心血管事件发生中的重要性日益引起人们的关注, 应变及应变率成像技术为评价左心房功能提供了新方法。随着该技术的不断发展, 其在评价左心房功能的应用中越来越广泛和深入。本文对应变及应变率成像评价左心房功能方面的研究进展进行综述。     

应变和应变率在缺血性心脏病中的应用进展

在缺血性心脏病患者的诊断和治疗中，于急性心肌梗死（AMI）早期或慢性心肌缺血患者心肌整体功能受损前评价局部心肌收缩功能、确认功能异常心肌中存活心肌有重要价值。超声心动图检出的节段性室壁运动异常是较心电图ST段压低和心绞痛出现更早和更敏感的指标，而组织多普勒成像（TDI）及其相关技术提高了对缺血心肌的诊断水平。     

应变和应变率对早期发现糖尿病性心肌病的应用价值

目的探讨应变和应变率在发现早期糖尿病性心肌病中的应用价值。方法应用GEVivid5超声诊断仪及应变和应变率分析软件,检测137例受试者的心肌左心室6个室壁节段应变和应变率,其中单纯糖尿病组36例,糖尿病合并左心室肥厚组23例,单纯左心室肥厚组42例,正常对照组36例。结果患者组的心脏收缩及舒张功能均低于正常对照组(P<0.001),最大收缩期应变和应变率绝对值亦均低于正常对照组(P<0.05);最大收缩期应变和应变率在糖尿病合并左心室肥厚组低于单纯糖尿病组(P<0.05),亦低于单纯左心室肥厚组(P<0.01)。结论应变和应变率可以早期发现无明显心脏病表现的糖尿病性心肌病。     

Left ventricular strain and left atrial strain are impaired during hemodialysis in children

The International Journal of Cardiovascular Imaging - We aimed to investigate intradialytic changes in ventricular and atrial function using speckle tracking echocardiography (STE) in pediatric...