2型糖尿病患者跟腱病变的超声特征

目的利用剪切波弹性成像(SWE)评估2型糖尿病(T2DM)跟腱截面积、周长、厚径及生物学弹性的变化,并探讨T2DM患者跟腱剪切波速度与糖化血红蛋白水平之间的相关性。方法收集T2DM患者及健康体检志愿者各50例。测量跟腱中段横截面积、周长及厚径,剪切波弹性成像测量该处跟腱弹性的剪切波速度(SWV),记录T2DM患者的入院糖化血红蛋白值,绘制剪切波速度与T2DM患者糖化血红蛋白水平的相关性散点图。结果受试者左、右侧中段跟腱弹性对比及性别间对比均无统计学意义(P>0.05);对照组跟腱各参数较A组均无统计学意义(P>0.05),较B组仅SWV值有统计学意义(P<0.05),较C组跟腱周长、厚径、截面积及SWV均有显著差异,且差异有统计学意义(P<0.05);A组较B组仅SWV有统计学差异(P<0.05),A组较C组除周长无统计学意义外,其余参数均有统计学差异(P<0.05);B组较C组截面积与SWV值两参数统计学差异显著(P<0.05)。相关性分析显示,糖化血红蛋白水平与跟腱SWV值显著相关(r=0.601,P<0.05),糖化血红蛋白值越高对跟腱生物学弹性的影响也就越大。结论SWE技术可定量评估T2DM患者跟腱生物学弹性的改变,为临床医师在预防糖尿病下肢病变的过程中提供参考。     

超声剪切波弹性成像在脑卒中患者小腿康复评定中的应用

目的 探讨超声剪切波弹性成像对脑卒中下肢运动障碍患者小腿三头肌和跟腱进行康复评定的价值。方法 2018年至2019年,脑卒中后单侧下肢运动障碍住院患者32例,于康复治疗前后,对患者双侧小腿三头肌和跟腱行超声二维测量和剪切波弹性成像检查,记录剪切波速度(SWV)以及跟腱(比目鱼肌肌腱)长度和厚度。结果 治疗前,患侧跟腱和小腿三头肌SWV较健侧增高(t > 2.426, P < 0.05);患侧跟腱长度较健侧显著增加( t = 11.801, P < 0.001);治疗后,患侧小腿三头肌SWV减低( t > 2.447, P < 0.05);患侧跟腱长度显著缩短( t = 8.577, P < 0.001)。 结论 康复治疗可降低脑卒中下肢运动障碍患者小腿三头肌肌张力。超声剪切波弹性成像可用于评价跟腱和小腿三头肌弹性特征,指导脑卒中康复。     

实时剪切波弹性成像技术评估跟腱急性闭合性损伤

目的 探讨采用实时剪切波弹性成像（SWE）技术根据跟腱硬度评价急性跟腱闭合性损伤的临床价值。方法 对49例跟腱急性闭合性损伤患者行高频超声及实时SWE检查，获得患侧和健侧跟腱的杨氏模量值和剪切波速度（SWV），比较完全断裂跟腱、不完全断裂跟腱与正常侧跟腱的差异。结果 经手术证实跟腱完全断裂患者36例，高频超声均诊断正确；经MRI证实，跟腱不完全断裂13例，其中超声正确诊断10例，漏诊3例。跟腱完全断裂组、跟腱部分断裂组和正常跟腱组跟腱杨氏模量值分别为（130.02±24.64） kPa、（281.08±84.36） kPa和（546.51±48.52） kPa，SWV分别为（6.23±1.04） m/s、（9.05±0.97） m/s和（14.33±1.41） m/s，3组间总体差异和两两比较差异均有统计学意义（P均<0.05）。结论 超声弹性成像可以作为高频超声诊断跟腱急性闭合性损伤的有效补充。     

剪切波弹性成像在辅助软组织松解术后跟腱功能评估中的应用

目的 利用高频超声剪切波弹性成像评估辅助软组织松解术(IASTM)对健康成人跟腱的作用。方法 2020年7月至12月,健康成人受试者52例随机分入对照组(n = 15)和试验组(n = 37)。试验组接受左侧跟腱IASTM治疗,隔天1次,共2周;对照组不作处理。治疗前、首次治疗后即刻、治疗后3 d,采用高频超声和超声剪切波弹性成像测量受试者左侧跟腱厚度和弹性模量。结果 末次治疗后,试验组5例脱失。治疗前,两组左跟腱厚度、弹性模量均无显著性差异(t < 0.63, P > 0.05)。治疗后即刻,试验组左跟腱厚度较对照组减少(t = 2.149, P < 0.05);治疗后3 d,左跟腱弹性模量平均值和最大值较对照组减少(t > 2.134, P < 0.05)。结论 超声剪切波弹性成像可以量化评估IASTM对跟腱的疗效。     

Mechanical properties of the human Achilles tendon, in vivo

Background

Ultrasonography has been widely applied for in vivo measurements of tendon mechanical properties. Assessments of human Achilles tendon mechanical properties have received great interest. Achilles tendon injuries predominantly occur in the tendon region between the Achilles-soleus myotendinous junction and Achilles-calcaneus osteotendinous junction i.e. in the free Achilles tendon. However, there has been no adequate ultrasound based method for quantifying the mechanical properties of the free human Achilles tendon. This study aimed to: 1) examine the mechanical properties of the free human Achilles tendon in vivo by the use of ultrasonography and 2) assess the between-day reproducibility of these measurements.

Methods

Ten male subjects had the Achilles tendon moment arm length, Achilles tendon cross sectional area and free Achilles tendon length determined. All subjects performed isometric plantarflexion ramp contractions to assess between-day reproducibility on two separate days. Simultaneous ultrasonography based measurements of Achilles-soleus myotendinous junction and Achilles-calcaneus osteotendinous junction displacement together with Achilles tendon force estimates yielded free Achilles tendon mechanical properties.

Findings

Free Achilles tendon maximal force, deformation and stiffness were 1924 (SD 229) N, 2.2 (SD 0.6) mm and 2622 (SD 534) N/mm on day 1. For between-day reproducibility there were no significant differences between days for free Achilles tendon mechanical properties. The between-day correlation coefficient and typical error percent were 0.81 and 5.3% for maximal Achilles tendon force, 0.85 and 11.8% for maximal Achilles tendon deformation and 0.84 and 8.8% for Achilles tendon stiffness respectively. Last, osteotendinous junction proximal displacement on average contributed with 71 (SD 12) % of proximal myotendinous junction displacement.

Interpretation

This study, for the first time, presents an ultrasonography based in vivo method for measurement of free AT mechanical properties. The method is applicable for evaluation of free human Achilles tendon mechanical properties in relation to training, injury and rehabilitation.     

Quantification of Mechanical Properties in Healthy Achilles Tendon Using Continuous Shear Wave Elastography: A Reliability and Validation Study

The purposes of this study were to (i) evaluate the intra-rater reliability of estimating Achilles tendon mechanical properties with continuous shear wave elastography (cSWE), (ii) propose an equivalent shear modulus comparable to Supersonic Shear Imaging, (iii) demonstrate construct validity of cSWE and (iv) explore relationships between tensile and shear properties. Achilles tendon mechanical properties were estimated with cSWE at four time points throughout a 4-h period and at a 2-wk follow up. Additionally, properties were estimated with cSWE across four different ankle positions. In these four positions, B-mode ultrasound imaging and dynamometry were used to quantify Young's modulus. Intra-rater reliability was fair-to-excellent for Achilles tendon mechanical properties estimated with cSWE. Construct validity was demonstrated with increased ankle dorsiflexion leading to increased mechanical properties. Linear relationships were found between tensile and shear mechanical properties. Findings demonstrate that cSWE has sufficient intra-rater reliability and validity for estimating Achilles tendon mechanical properties.     

Quantitative Assessment of Healthy Skin Elasticity: Reliability and Feasibility of Shear Wave Elastography

The goal of this study was to investigate the reliability and feasibility of shear wave elastography by assessing the elasticity of the healthy skin of 40 volunteers. Young's moduli for bilateral fingers, forearms, anterior chest (sternum), and anterior abdomen were determined with both transverse and longitudinal sectional measurements. Reliability of measurements was evaluated using intra- and inter-class correlation coefficients with two observers. Our results revealed that the elastic modulus values of the skin between symmetric parts of fingers and forearms did not statistically different. No differences were found between the transverse and longitudinal sections of forearms, anterior chest, and abdomen (p > 0.05), except for middle fingers (p = 0.004). Inter-observer and intra-observer repeatability (inter- and intra-class correlation coefficients) varied from moderate to excellent depending on the skin site (0.62–0.91). In conclusion, shear wave elastography reached a good consistency in measuring healthy skin elasticity. Further studies are needed to provide more information on the factors that influence the reliability of shear wave elastography measurements in both healthy and diseased skin.     

Quantification of Ultrasound Correlation‐Based Flow Velocity Mapping and Edge Velocity Gradient Measurement

This study investigated the use of ultrasound speckle decorrelation‐ and correlation‐based lateral speckle‐tracking methods for transverse and longitudinal blood velocity profile measurement, respectively. By studying the blood velocity gradient at the vessel wall, vascular wall shear stress, which is important in vascular physiology as well as the pathophysiologic mechanisms of vascular diseases, can be obtained. Decorrelation‐based blood velocity profile measurement transverse to the flow direction is a novel approach, which provides advantages for vascular wall shear stress measurement over longitudinal blood velocity measurement methods. Blood flow velocity profiles are obtained from measurements of frame‐to‐frame decorrelation. In this research, both decorrelation and lateral speckle‐tracking flow estimation methods were compared with Poiseuille theory over physiologic flows ranging from 50 to 1000 mm/s. The decorrelation flow velocity measurement method demonstrated more accurate prediction of the flow velocity gradient at the wall edge than the correlation‐based lateral speckle‐tracking method. The novelty of this study is that speckle decorrelation‐based flow velocity measurements determine the blood velocity across a vessel. In addition, speckle decor‐relation‐based flow velocity measurements have higher axial spatial resolution than Doppler ultrasound measurements to enable more accurate measurement of blood velocity near a vessel wall and determine the physiologically important wall shear.     

Strain measurements of rabbit Achilles tendons by ultrasound

Axial components of tendons' transverse strain fields were successfully measured in vitro by ultrasound. Achilles tendons of New Zealand white rabbits were used. Tendon inflammation was simulated by artificially inducing ischemia. Strain measurements were also correlated with conventional B-mode sonograms and histological micrographs. Results showed that strain measurements had reasonable agreement with histological examinations and provided better tissue differentiation than conventional B-mode imaging. For a given tendon, the strain values corresponding to different tissue layers were easily differentiated with an elastographic contrast-to-noise ratio ranging from 17 to 43 dB. Such differences, however, were not always present in the sonograms. Therefore, ultrasonic strain imaging may be a useful tool for assessing tendon disorders during the rehabilitation process.     

Proposing a Minimal Data Set of Musculoskeletal Ultrasound Imaging Biomarkers to Inform Clinical Practice: An Analysis Founded on the Achilles Tendon

Tendon integrity can be described using a wide range of biomarkers via specialized analysis software for images recorded by musculoskeletal ultrasonography. This study proposes a minimal biomarker data set to characterize Achilles tendon ultrasound images and to differentiate between symptomatic and asymptomatic Achilles tendon images. Forty-one individuals with unilateral Achilles tendinopathy and 35 healthy controls had their Achilles tendon images recorded bilaterally by ultrasonography in the longitudinal and transverse planes. A set of 22 biomarkers, organized around three dimensions (geometric, composition and texture), were computed in each plane. A symmetry index, reflecting relative side differences, was compared between groups and analyzed through principal component analysis to isolate biomarkers that best explained data variance. A specific minimal data set was identified by linear regression in the longitudinal (mean thickness, echogenicity, variance and homogeneity at 90°) and transverse (mean thickness, echogenicity and mean homogeneity) planes to characterize and differentiate Achilles tendon integrity.     

Sonographic Elastography of Mastitis

Sonographic elastography has been shown to be a useful imaging modality in characterizing breast lesions as benign or malignant. However, in preliminary research, mastitis has given false‐positive findings on both strain and shear wave elastography. In this article, we review the findings in mastitis with and without abscess formation on both strain and shear wave elastography. The elastographic findings in all cases were suggestive of a malignancy according to published thresholds. In cases of mastitis with abscess formation, there is a characteristic appearance, with a central very soft area (abscess cavity) and a very stiff outer rim (edema and inflammation). This appearance should raise the suspicion of mastitis with abscess formation, since these findings are rare in breast cancers.     

Reliability Indicators for 2‐Dimensional Shear Wave Elastography

Ultrasound (US) shear wave technology providers have either point shear wave elastography (SWE) or 2‐dimensional SWE available on their US systems. With 2‐dimensional SWE, larger regions of interest can be interrogated, with both the main acoustic radiation pulses and the resultant shear waves potentially being affected by US artifacts. Some providers assist the operator with elastographic maps indicating the reliability or precision of the shear wave propagation. This Technical Innovation explores the importance of the consideration of the precision maps and standard deviation output available on some devices and the implications for conversion of shear wave speed to pressure.     

高压氧联合超短波辅助治疗兔跟腱断裂的实验研究

目的探讨高压氧联合超短波辅助治疗跟腱断裂对跟腱愈合的影响。 方法将80只新西兰白兔切断跟腱,制造模型,均行Kessler法缝合,并石膏超踝膝固定4周后拆除。随机分为高压氧组（A组）、超短波组（B组）、高压氧联合超短波组（C组）、对照组（D组）,每组20只。A组、C组术后即刻行高压氧治疗,前3天每天2次,后4天每天1次,共治疗7 d。B组、C组术后每天给予超短波治疗,共6 d,D组不予治疗。术后分别于4周、8周各组分别处死10只白兔,取跟腱组织行生物力学检测（最大拉伸长度和最大抗拉力）、HE染色和免疫组织化学染色。采用方差分析比较术后4周和8周生物力学检测结果的组间差异,并采用LSD-t检验进行组间的两两比较。 结果生物力学测试结果显示：术后4周A组、B组、C组跟腱平均最大抗拉力和平均最大拉伸长度与D组相比显著升高[最大抗拉力：（276.20±8.16）N vs（278.10±7.92）N vs（309.90±9.78）N vs（259.50±4.99）N;最大拉伸长度：（4.62±0.14）mm vs（4.67±0.16）mm vs（5.05±0.17）mm vs（4.18±0.32）mm],差异均具有统计学意义（最大抗拉力：t=5.519、6.280、14.513,P均<0.001;最大拉伸长度：t=3.934、4.136、7.563,P=0.001、<0.001、<0.001）,且C组更优于A组及B组,差异均具有统计学意义（最大抗拉力：t=8.366、7.989,P均<0.001;最大拉伸长度：t=6.164、5.190,P均<0.001）。术后8周A组、B组、C组跟腱平均最大抗拉力和平均最大拉伸长度与D组相比显著升高[最大抗拉力：（354.60±5.68）N vs（355.30±9.62）N vs（390.70±7.48）N vs（339.60±5.60）N;最大拉伸长度：（4.88±0.18）mm vs（5.10±0.16）mm vs（5.38±0.15）mm vs（4.46±0.23）mm],差异均具有统计学意义（最大抗拉力：t=5.946、4.461、17.286,P均<0.001;最大拉伸长度：t=4.578、7.327、10.628,P均<0.001）,且C组更优于A组及B组,差异均具有统计学意义（最大抗拉力：t=12.150、9.187,P均<0.001;最大拉伸长度：t=6.600、3.925,P<0.001、=0.001）。组织学观察结果：C组发现大量成纤维细胞在跟腱断端附近增生,并有少量炎性细胞。A组和B组中虽然可见大量成纤维细胞,但较C组少,且炎性细胞数量较多。D组镜下炎性细胞数量显著多于其他3组,成纤维细胞生长情况明显落后于其他3组,且排列杂乱,并见较多肉芽组织。免疫组织化学染色检查：术后可见Ⅰ型胶原纤维呈现阳性表达,且C组Ⅰ型胶原纤维表达数目最为丰富,B组略多于A组,D组最少。 结论高压氧联合超短波可促进跟腱断裂后跟腱愈合生物学性能,促进Ⅰ型胶原纤维合成。     

肝脏剪切波弹性成像影响因素的研究进展

剪切波弹性成像可通过探测组织内剪切波传播速度定量反映组织硬度,可用于无创评估肝纤维化。纤维化程度被认为是影响肝脏弹性的重要影响因素,但随着研究的深入,发现还有诸多因素对肝脏弹性测值准确性有影响。本文对炎症、脂肪肝、胆汁淤积、肝脏淤血、进食、呼吸、肥大细胞增多症、性别和年龄、测量深度和次数对肝脏剪切波弹性成像的影响进行综述。     

Sonoanatomy of the Achilles tendon insertion in children

PURPOSE: The aim of this study was to describe typical age-related sonographic features of the Achilles tendon and calcaneal apophysis in children, providing a reference for the assessment of heel pathologies during the growth period. METHODS: The calcaneal apophysis and Achilles tendon insertion of 100 children 2 months to 18 years old were examined by high-frequency gray-scale and color Doppler sonography along both the longitudinal and transverse planes. The thicknesses of the apophyseal cartilage at the calcaneal tuberosity and of the Achilles tendon were measured. Also, the sonographic appearance of the bone-cartilage interface was studied. RESULTS: In children 2 months to 3 years old, the cartilage of the calcaneal tuberosity apophysis was anechoic, with small scattered echoes. In 19 of these 25 children (76%), the echogenic areas contained at least 1 small vessel, visualized on color Doppler sonography. In 15 of 25 children (60%) 4-6 years old, a wavy interface was noted at the junction of the calcaneus and the apophyseal cartilage. CONCLUSIONS: High-frequency sonography can yield reliable information about the bone-cartilage interface and the Achilles tendon insertion site at the calcaneal tuberosity in children. The sonographic features of the normal heel described here may contribute to improved assessment of pathologies in this anatomic region.     

Visualizing Tendon Elasticity in an ex Vivo Partial Tear Model

Supersonic shear imaging (SSI) is evaluated as a means of visualizing changes in regional tendon elasticity caused by partial tears in a porcine model. Thirty digital flexor tendons were cut to 25% (n = 10), 50% (n = 10) and 75% (n = 10) of the tendon thickness along the deep surface. Tendon elasticity was mapped left of, centered on and right of the tear site before and after tearing from 0% to 2% strain. Shear wave speed increased at 1% (p < 0.05) and 2% (p < 0.001) strain for all regions. Deep surface shear wave speed decreased in the 25%, 50% and 75% tears (p < 0.05 and p < 0.001). Computational tendon tear models were also created to investigate regional changes in strain resulting from a tear. In the computational models, strain on the deep surface decreased progressively with increasing tear size. Visualization of tendon shear wave speed was achieved in normal and partially torn tendons, indicating the potential of SSI to add tendon shear wave speed to traditional morphologic assessment of partial tears, which may improve assessment of tendon health.     

健康人群四肢近端肌肉剪切波弹性成像测量的初步研究

目的测量健康人群四肢近端肌肉剪切波速度,分析与其相关的因素。 方法选取2019年1月至2020年12月在四川大学华西医院招募的健康志愿者88例,记录受检者的性别、年龄、体质量指数（BMI）及运动习惯。测量不同肌肉（三角肌、肱二头肌、股直肌、股外侧肌）左右两侧及相同肌肉不同断面、不同位置及不同体位的剪切波速度,并对不同性别、年龄、BMI及运动状态的肌肉剪切波速度进行比较。随机抽取20例受试者,计算三角肌及股直肌剪切波速度测量的观察者间及观察者内一致性。 结果各肌肉纵断面剪切波速度左、右两侧比较,差异无统计学意义（P均＞0.05）。各肌肉剪切波速度纵断面均大于横断面（P均＜0.05）。肱二头肌伸直位纵断面,其剪切波速度肌腹外侧大于肌腹内侧（P均＜0.05）。肱二头肌剪切波速度伸直位均大于屈曲位（P均＜0.05）。三角肌、肱二头肌剪切波速度男性高于女性（P均＜0.05）。股外侧肌剪切波速度18~49岁组高于50~70岁组（P＜0.05）。肱二头肌剪切波速度BMI＜18.5 kg/m²组及18.5 kg/m²≤BMI＜24 kg/m²组均高于BMI≥24 kg/m²组,差异均有统计学意义（P均＜0.05）。三角肌剪切波速度规律运动者高于少运动者,差异有统计学意义（P＜0.05）。三角肌及股直肌的剪切波速度观察者内及观察者间一致性均为良好或优秀（ICC均＞0.88）。 结论剪切波弹性成像（SWE）能够用于定量测量健康人群肌肉的硬度值,肌肉的断面和部位及受检者的体位、性别、年龄、BMI和运动习惯为与其相关的因素,研究结果为特发性炎性肌病的进一步研究提供了依据。     

超声监测跟腱断裂手术治疗后跟腱周长及断端血流动态变化的价值

目的 探讨超声监测跟腱周长及断端血流在跟腱手术治疗后恢复过程中的意义.方法 对31例跟腱断裂修补术后不同时期的患者,超声动态观察跟腱术后断端的血流变化,用轨迹测量法测量健侧和患侧跟腱多点的周长.结果 跟腱断裂后患侧跟腱周长较健侧大(P＜0.05).术后随着修复时间的延长,患侧跟腱周长有逐渐变小的趋势,但仍较同时期健侧跟腱的周长值大.跟腱术后8周,跟腱断端的血流信号由丰富逐渐减少.结论 监测跟腱术后周长及断端血流的变化可以准确跟踪跟腱术后的动态演变过程.     

Sonographic Measurement of Achilles Tendons in Asymptomatic Subjects

Objective. This study was undertaken to evaluate the thickness, cross‐sectional area, and length of Achilles tendons in asymptomatic subjects of different age groups and heights and between dominant and nondominant ankles. Methods. High‐resolution sonographic examinations of Achilles tendons were performed in 40 healthy subjects (14 men and 26 women). The subjects were categorized into 4 age groups: (1) 20 to 29 years, (2) 30 to 39 years, (3) 40 to 49 years, and (4) 50 years or older. The thickness, cross‐sectional area, and length of the Achilles tendons of both ankles were measured. All Achilles tendons were measured with the ankle in a relaxed, neutral position. Results. There was no significant difference in the thickness and length of Achilles tendons among subjects of different age groups (P > .05). The Achilles tendon cross‐sectional area of subjects 50 years or older was significantly larger than that of subjects in the younger age groups (P < .05). There was a positive correlation between the height of the subjects and the length, thickness, and cross‐sectional area of the Achilles tendons; however, the correlation coefficient was low (r = 0.07–0.28; P > .05). Dominance of ankles did not affect the thickness and length of the Achilles tendons, whereas the cross‐sectional area of the tendons was significantly larger in the dominant ankles (P < .05). Conclusions. Sonography is a useful imaging tool in the evaluation of Achilles tendons. Normal variations of the tendon morphologic characteristics should be considered in the clinical diagnosis.     

Cardiac Shear Wave Velocity Detection in the Porcine Heart

Cardiac muscle stiffness can potentially be estimated non-invasively with shear wave elastography. Shear waves are present on the septal wall after mitral and aortic valve closure, thus providing an opportunity to assess stiffness in early systole and early diastole. We report on the shear wave recordings of 22 minipigs with high-frame-rate echocardiography. The waves were captured with 4000 frames/s using a programmable commercial ultrasound machine. The wave pattern was extracted from the data through a local tissue velocity estimator based on one-lag autocorrelation. The wave propagation velocity was determined with a normalized Radon transform, resulting in median wave propagation velocities of 2.2 m/s after mitral valve closure and 4.2 m/s after aortic valve closure. Overall the velocities ranged between 0.8 and 6.3 m/s in a 95% confidence interval. By dispersion analysis we found that the propagation velocity only mildly increased with shear wave frequency.