Shear wave elasticity imaging of cervical lymph nodes

A pilot study of real-time shear wave ultrasound elastography (SWE) for cervical lymphadenopathy in routine clinical practice was conducted on 55 nodes undergoing conventional ultrasound (US) with US-guided needle aspiration for cytology. Elastic moduli of stiffest regions in nodes were measured on colour-coded elastograms, which were correlated with cytology. Malignant nodes (n = 31, 56.4%) were stiffer (median 25.0 kPa, range 6.9-278.9 kPa) than benign nodes (median 21.4 kPa, range 8.9-30.2 kPa) (p = 0.008, Mann Whitney U test). A cut-off of 30.2 kPa attained highest accuracy of 61.8%, corresponding to 41.9% sensitivity, 100% specificity and 0.77 area under the receiver operating characteristic curve. Qualitatively, elastograms of benign nodes were homogeneously soft; malignant nodes were homogeneously soft or markedly heterogeneous with some including regions lacking elasticity signal. SWE is feasible for neck nodes. It appears unsuitable for cancer screening but may detect a subset of malignant nodes. The cause of spatial heterogeneity of malignant nodes on SWE is yet to be established.     

超声诊断颈部转移性与淋巴瘤性淋巴结中的应用价值

目的探讨超声在诊断颈部转移性与淋巴瘤性淋巴结中的应用价值。方法 2007年1月-2008年12月对经病理证实的102例患者120个颈部淋巴结,应用二维超声、能量多普勒显像（PDI）分为两组：转移性淋巴结68个,淋巴瘤性淋巴结52个。对淋巴结长短比（L/S）、结构及血流分布状态进行分析。结果两组淋巴结门消失、局部液化灶、中央血流率比较差异有统计学意义（P〈0.05）,两组出现淋巴结形态不规则、皮质回声减低、淋巴门型血流、周围型血流率比较差异有统计学意义（P〈0.05）。两组的L/S≤2淋巴结无统计学差异（P〉0.05）。结论超声检查对颈部转移性淋巴结与淋巴瘤性淋巴结的鉴别诊断有较高价值。     

超声弹性成像在判断腋窝淋巴结性质中的应用

目的 探讨超声弹性成像技术判断腋窝淋巴结性质的价值.方法 应用弹性成像技术检查40例乳腺癌患者62个腋窝淋巴结,对腋窝淋巴结采用四分法进行评分,与手术病理结果对照.结果 62个淋巴结中良性反应性增生38个,恶性转移性病变24个.弹性图中良性病变以1～2分多见,为84.2％ (32/38),恶性转移性病变以3～4分多见,为87.5％ (21/24),两组比较差异有统计学意义(Z值-5.619,P＜0.05).恶性组评分(3.12±0.61)明显高于良性组(1.68±0.74),两组比较差异有统计学意义(t＝8.318,P＜0.05).以弹性评分≥3分作为判断腋窝淋巴结良恶性病变的标准,其敏感度、特异度、准确率分别为77.8％、91.4％、85％.结论 超声弹性成像可为判断腋窝淋巴结的性质提供有价值的信息.     

实时超声弹性成像在淋巴结疾病诊断中的应用

目的探讨实时超声弹性成像在淋巴结疾病诊断中的应用价值。方法分析2008年2月-4月27例淋巴结疾病患者的65个淋巴结病灶超声弹性图表现,弹性图分级为0～Ⅳ级,弹性图分型为Ⅰ～Ⅲ型。所有淋巴结均经术后病理学或细针抽吸细胞学检查证实,或经随访证实。结果转移性淋巴结弹性分级较高,≥Ⅲ级11/13,占84.62%;淋巴瘤性淋巴结弹性分级较低,≤Ⅱ级16/21,占76.19%。转移性淋巴结中Ⅱ型7/13,占53.85%,转移性淋巴结占全部Ⅱb型的54.55%（6/11）;淋巴瘤性淋巴结中Ⅱ型13/21,占61.90%,淋巴瘤性淋巴结占全部Ⅱa型的73.33%（11/15）;反应性淋巴结占全部Ⅰa型的68.18%（15/22）。结论实时超声弹性成像能为淋巴结疾病的诊断提供一定信息,弹性图分级对鉴别良恶性淋巴结有统计学意义,分型对于鉴别特定类型淋巴结疾病有一定提示作用。     

Real-time qualitative ultrasound elastography of cervical lymph nodes in routine clinical practice: interobserver agreement and correlation with malignancy

To evaluate real-time qualitative ultrasound (US) elastography for cervical lymphadenopathy in routine clinical practice, 74 nodes (37 malignant, 37 benign) in 74 patients undergoing sonography underwent US elastography prior to fine needle aspiration for cytology. Dynamic cine loops of elasticity imaging displayed using a chromatic-scale were qualitatively scored by three independent observers for the proportion of stiff areas from ES1-4 (soft to stiff). There was fair to good interobserver agreement as indicated by weighted kappa (κ) statistic from 0.374 to 0.738. Median ES for benign and malignant nodes were 2 and 3 respectively. ES was higher in malignant nodes (p = 0.0003-0.0049, Mann Whitney U tests) although areas under receiver operating characteristic curves (0.68-0.74) indicated suboptimal discrimination. The optimal discriminatory cut-off, ES > 2, achieved only 62.2% sensitivity, 83.8% specificity and 73% accuracy for malignancy. Improvements in reliability and accuracy of real-time qualitative ultrasound elastography are required for it to be adopted into routine clinical practice.     

Three-Dimensional Elastography for Cervical Lymph Node Volume Measurements: A Study to Investigate Feasibility,Accuracy and Reliability

This study investigated the feasibility of using three-dimensional (3-D) elastography in measuring cervical lymph node volume and compared the accuracy and reliability of 3-D elastography and 3-D grayscale ultrasound in measurement of ill-defined cervical nodes. Eighteen porcine lymph nodes from the neck were embedded in tissue-mimicking phantoms and scanned with the two ultrasound techniques. Ultrasound measurements were compared with the volume determined by water-displacement method to evaluate measurement accuracy. Inter-observer reproducibility and intra-observer repeatability of measurements were evaluated. Four patients with enlarged neck nodes were included to evaluate intra-observer repeatability of ultrasound measurements. Results demonstrated that lymph nodes that appeared ill-defined on grayscale ultrasound showed well-defined boundaries on elastography. 3-D elastography has higher measurement accuracy (84.2%), reproducibility (intraclass correlation coefficient, ICC = 0.909) and repeatability (ICC = 0.964–0.988) than does 3-D grayscale ultrasound (62.2%, 0.777 and 0.863–0.906 respectively). As a conclusion, 3-D elastography is accurate and reliable in volume measurement of ill-defined lymph nodes and has potential for accurate assessment of lymph node volume.     

常规超声和超声弹性成像在颈部淋巴结良恶性鉴别诊断中的价值

目的:对比实时静态超声弹性成像技术与二维灰阶、彩色多普勒等传统超声方法在判断颈部淋巴结良恶性中的诊断价值。方法:选取2012年1月—2013年12月诊治的311例颈部淋巴结肿大患者(共322个颈部淋巴结),所有淋巴结均经病理学证实良恶性。采用灰阶超声进行病灶检查,记录淋巴结的长径、短径,并计算长短径的比值。采用彩色多普勒超声对淋巴结进行血管模式分型,分为淋巴门型、中央型、周围型及混合型,并记录血流阻力指数(RI)值。对病灶行超声弹性成像,根据弹性图显示图像将感兴趣区(ROI)内病灶区与周围组织硬度相比较,并对弹性图进行分型。绘制受试者工作特征(receiver operating characteristic,ROC)曲线,评价各项指标对颈部浅表淋巴结良恶性的诊断价值。结果:322个颈部淋巴结中经病理证实良性淋巴结73个,恶性淋巴结249个。长短径比值截断值1.5789,曲线下面积0.766,准确性65.22%,敏感性61.40%,特异性78.10%。RI截断值0.655,曲线下面积0.787,准确性72.98%,敏感性73.10%,特异性72.60%。血管模式中,淋巴门型恶性病变率11.8%,中央型恶性病变率52.9%,周围型恶性病变率83.3%,混合型恶性病变率88.8%,其差异有统计学意义(P0.01)。以弹性分级≥Ⅲ级作为判断淋巴结良恶性的标准,249个恶性淋巴结中弹性分级≥Ⅲ级222个,73个良性淋巴结中弹性分级≤Ⅱ级31个,超声弹性分级诊断颈部淋巴结良恶性准确性为78.57%。长短径比值、RI、超声弹性分级用于诊断颈部淋巴结良恶性的准确性差异有统计学意义(P0.05)。结论:淋巴结长短径比值、RI、血管模式分型、超声弹性图分级对于判断颈部淋巴结的良恶性有诊断价值,超声弹性分级用于判断颈部淋巴结良恶性的准确性优于RI及长短径比值,RI优于长短径比值。血管模式分型为周围型及混合型的淋巴结恶性病变率高于中央型及淋巴门型。     

Quantitative and Qualitative Approach for Shear Wave Elastography in Superficial Lymph Nodes

The diagnostic contribution of 2-D shear-wave elastography (SWE) in management of superficial lymph nodes (LNs) of any origin was evaluated in 222 patients referred for needle core biopsy. Each patient underwent conventional B-mode/Doppler ultrasound examinations (conventional ultrasound) and SWE. Quantitative SWE parameters and qualitative SWE map features were extracted. Carcinomas were found to be significantly stiffer than benign LNs (29.5 ± 32.3 kPa vs. 6.7 ± 12.3 kPa). Lymphomas exhibited intermediate stiffness (11.4 ± 5.2 kPa). Qualitative SWE analysis provided color patterns specific to histopathology (stiff rim, nodular and undetermined patterns related to malignancy and blue pattern to benignity). Adding SWE to conventional ultrasound improved the sensitivity of LN diagnosis (from 81.1% to 92.0%) but decreased its specificity (from 73.2% to 67.6%) because of the high prevalence of lymphomas compared with carcinomas. Inter-observer agreement for quantitative SWE was good (intra-class correlation coefficient = 0.82) as was inter-observer diagnostic agreement for qualitative SWE (κ = 0.65). LN location and histology type were found to influence the reported diagnostic performance of SWE.     

Evaluation of Post-Stroke Spastic Muscle Stiffness Using Shear Wave Ultrasound Elastography

Current clinical evaluations of post-stroke upper limb spasticity are subjective and qualitative. We proposed a quantitative measurement of post-stroke spastic muscle stiffness by using shear-wave ultrasound elastography and tested its reliability. Acoustic radiation force impulse with shear wave velocity (SWV) detection was used to evaluate stiffness of the biceps brachii muscles at 90° and 0° elbow flexion. In 21 control subjects, SWV did not significantly differ between dominant and non-dominant sides at either flexion angle (0°: p = 0.311, 90°: p = 0.436). In 31 patients who had recent stroke, SWV was significantly greater on the paretic side than on the non-paretic side at both 90° (2.23 ± 0.15 m/s vs. 1.88 ± 0.08 m/s, p = 0.036) and 0° (3.28 ± 0.11 m/s vs. 2.93 ± 0.06 m/s, p = 0.002). The physical appearance of arms and forearms of our patients and controls prevented blinding of the rater to paretic or non-paretic side. At 90°, SWV on the paretic side correlated positively with modified Ashworth scale and modified Tardieu scale (spasticity severity) and negatively with Stroke Rehabilitation Assessment of Movement score (motor function impairment). The intra-class correlation coefficients of intra-rater and inter-rater reliability for SWV measurements were classified as excellent. In conclusion, high SWV was associated with high spasticity and poor function of the post-stroke upper limb, suggesting possible use as a reliable quantitative measure for disease progression and treatment follow-up.     

超声弹性成像在颈部淋巴结结核诊断的价值

目的探讨超声弹性成像在颈部淋巴结结核(CTL)诊断的价值。方法选取98例因CTL就诊的患者为研究对象,选择每例患者最大淋巴结,对其均行常规超声、弹性成像及病理HE检查,对各项超声指标进行统计学分析。结果98例淋巴结结核患者均为多发性颈部淋巴结增大或多个淋巴结融合的颈部肿物。对最大淋巴结的超声表现判定Ⅰ型31枚,超声表现为淋巴结增大,呈类圆形,横纵比0.6~0.9,内部回声较低且不均匀,髓质破坏显著,皮质增厚,血流信号可见且丰富;Ⅱ型35枚,超声表现为淋巴结部分融合呈串珠样,体积较小,横纵比0.5~0.9,内部回声很低且不均匀,边缘不光滑,髓质消失,血流信号极少见,呈条状或短棒状;Ⅲ型19枚:超声表现为淋巴结增生增大显著,形态不规则,横纵比0.4~0.7,内部回声杂乱,内壁不均匀增厚,粗糙不平,伴有高回声的炎性水肿带,可见稀疏血流信号,以静脉血流为主;Ⅳ型13枚,超声表现为淋巴结萎缩,呈长条或椭圆形,横纵比0.3~0.6,内部回声低,血流信号不可见,可见钙化或纤维化灶。Ⅰ型:髓质破坏显著,皮质增厚。Ⅱ型:可见多个典型结核肉芽肿结构,肉芽肿中心无或者仅见微小干酪样坏死区。Ⅲ型:周边为不典型肉芽肿病变,散在朗罕氏细胞,多伴有显微组织增生,中央见大片融合干酪样坏死。Ⅳ型,皮质增厚,可见大片融合干酪样坏死。Ⅰ型、Ⅱ型的病灶硬度介于Ⅲ型与Ⅳ型之间,横纵比较高,Ⅲ型病灶硬度最低,弹性评分最低,横纵比介于Ⅰ型、Ⅱ型及Ⅳ型之间。Ⅳ型病灶硬度最高,弹性评分最高,横纵比较低。不同分型的淋巴结超声弹性评分和横纵比无线性关系(r=0.463,P=0.078)。结论超声弹性成像在诊断颈部淋巴结结核分型有一定的临床意义。     

Real-Time Qualitative Ultrasound Elastography of Miscellaneous Non-Nodal Neck Masses: Applications and Limitations

To evaluate real-time qualitative ultrasound elastography as an adjunct to conventional sonography for evaluation of non-nodal neck masses identified in routine clinical practice, 52 consecutive masses in 49 patients underwent both techniques. Lesion stiffness was graded visually on chromatic-scale elastograms from ES0-3 (low to high). Diagnosis was based on (cyto)pathology (11), corroborative cross-sectional imaging (18) or characteristic conventional sonography (23). There were 16 lipomas, 15 lymphatic/venous vascular malformations (LVVMs), six neurogenic tumours/neuromas, five thyroglossal duct cysts (TGCs), five (epi)dermoids, three abscesses, one second-arch branchial cleft cyst (BCC), and one soft-tissue metastasis. In general terms, lesion stiffness was high (ES2-3) for neurogenic tumours/neuromas, (epi)dermoids and metastasis, and low (ES0-1) for lipomas, LVVM, TGCs and BCC. Abscesses displayed variable stiffness according to fluid content. Technical limitations and artefacts of elastograms were identified. Data from real-time qualitative ultrasound elastography may be a useful adjunct to sonography for diagnosis of non-nodal neck masses (E-mail: aniltahuja@cuhk.edu.hk)     

颈部淋巴结淋巴瘤皮质回声及其病理基础的初步探讨

目的 描述颈部淋巴结淋巴瘤皮质回声,分析其与病理的相关性,以期有助于此类疾病的超声筛诊.方法 回顾性分析168例淋巴瘤患者的225个颈部受累淋巴结声像图,将淋巴结皮质回声分为均匀(低或极低回声)和不均匀(低回声背景下见点状、点条状、网格状、絮状稍高回声、无回声区),比较不同病理亚型之间上述声像图是否存在差异,并观察其中部分病例的病理切片.结果 颈部淋巴结淋巴瘤皮质回声多数是不均匀(占67.1％),且不同病理亚型间声像图的差异无统计学意义.结论 颈部淋巴结淋巴瘤病变内部所见的点状、点条状、网格状、絮状稍高回声多为增生的网状或胶原纤维组织,这些声像图特征对超声医师筛诊此类疾病有帮助.     

Artifacts in Shear Wave Elastography Images of Thyroid Nodules

The purpose of the study described here was to evaluate the presence and types of artifacts seen in color elastograms in thyroid elastography using shear wave elastography. This Health Insurance Portability and Accountability Act of 1996 (HIPAA)-compliant study was approved by the ethics committee of our institution, and all patients provided written informed consent. One hundred seventy-eight patients (40 men and 138 women; mean age, 49 y; range, 19–84 y) were enrolled for a total of 241 thyroid nodules. After a short ultrasound (US) examination, SWE images were acquired at multiple levels in the nodule in transverse and longitudinal orientations. A total of 1297 images were obtained from 241 nodules for an average of 5.4?±? 2.7 (mean?±?standard deviation) images per nodule. A retrospective review of all images was performed by one reviewer experienced in thyroid elastography. Two hundred eighty images (21.6%) were rated as good quality, and 112 (8.6%) were rated as moderate quality without artifacts. A total of 905 (69.8%) images had some artifact present, though most of these images (73.4%) were still interpretable. Two hundred forty-one images (18.6% of all images) were considered uninterpretable because of artifact. The most common types of artifacts were due to operator error (44.6% of all images), primarily compression (36.5% of all images). Other artifacts seen were due to anatomy (presence of carotid pulsation or adjacent to thyroid or location in isthmus, 11% of all images), nodule characteristics (cystic and calcified nodules or large nodules with lack of penetration, 17% of all images) and other artifacts that could not be explained by the prior mentioned causes (13% of all images). Our study indicates that artifacts are common in elastography images. Operator error was the most common type of artifact we saw. This should be easily correctable by adequate knowledge and recognition with subsequent correction of the artifacts.     

颈部转移性淋巴结的超声造影表现分析

目的 探讨颈部转移性淋巴结的超声造影表现特征.方法 对23例患者的52个颈部转移性淋巴结进行灰阶超声造影,观察造影图像表现.结果 52个转移性淋巴结中,36个(69%)淋巴结造影表现为显著增强的实质内有局灶性低或无灌注区;14个(27%)淋巴结造影表现为整个淋巴结微弱增强,灌注均匀或不均匀,其中的9个淋巴结造影同时表现为边界不清,与不均匀增强的周围软组织混合成一片,造影图像上无法辨认淋巴结的轮廓;2个(4%)淋巴结造影表现为整个淋巴结显著而均匀的增强.结论 超声造影能反映转移性淋巴结的灌注情况,对诊断有一定价值.     

剪切波弹性成像鉴别淋巴瘤与转移性淋巴结的价值

目的 探讨应用实时剪切波弹性成像(SWE)技术鉴别诊断淋巴瘤和转移淋巴结的临床价值。方法 对可疑结内淋巴瘤患者于活检前行常规超声及剪切波弹性成像检查,获取图像和指标。以病理结果为标准,得到淋巴瘤组25例,转移组30例。分析两组淋巴结各指标差异。通过ROC曲线评价用弹性模量均值鉴别两种恶性淋巴结的诊断效能。结果 二维超声指标中仅淋巴门消失与否存在统计学差异。两组间在取样框色彩充填是否完整及弹性模量值间存在显著差异。转移组淋巴结的弹性模量均值（30.01±13.26）kPa高于淋巴瘤组（14.43±2.46）kPa。淋巴结弹性模量均值鉴别淋巴瘤和转移淋巴结的灵敏度为83.3％。结论 SWE获取的颈部淋巴结弹性图像及弹性模量值可以为鉴别恶性淋巴结性质提供诊断依据。     

Pre-Operative Evaluation of Axillary Lymph Node Status in Patients with Suspected Breast Cancer Using Shear Wave Elastography

The aim of this study was to evaluate shear wave elastography (SWE) for pre-operative evaluation of axillary lymph node (LN) status in patients with suspected breast cancer. A total of 130 axillary LNs in 130 patients who underwent SWE before fine-needle aspiration, core biopsy or surgery were analyzed. On gray-scale images, long and short axes, shape (elliptical or round), border (sharp or unsharp) and cortical thickening (concentric, eccentric or no fatty hilum) of LNs were assessed. On SWE, mean, maximum, minimum, standard deviation and the lesion-to-fat ratio (E_ratio) values of elasticity were collected. Gray-scale and SWE features were compared statistically between metastatic and benign LNs using the χ²-test and independent t-test. Diagnostic performance of each feature was evaluated using the area under the receiver operating characteristic curve (AUC). Logistic regression analysis was used to determine gray-scale or SWE features independently associated with metastatic LNs. Of the 130 LNs, 65 (50%) were metastatic and 65 (50%) were benign after surgery. Metastatic LNs were significantly larger (p = 0.018); had higher elasticity indexes at SWE (p < 0.0001); and had higher proportions of round shape (p = 0.033), unsharp border (p = 0.048) and eccentric cortical thickening or no fatty hilum (p = 0.005) compared with benign LNs. On multivariate analysis, E_ratio was independently associated with metastatic LNs (odds ratio = 3.312, p = 0.008). E_ratio had the highest AUC among gray-scale (0.582–0.719) and SWE (0.900–0.950) variables. SWE had good diagnostic performance in metastatic axillary LNs, and E_ratio was independently associated with metastatic LNs.     

颈部淋巴结的超声诊断

本研究使用彩色多普勒观察７０例患者的８０个颈部良性及恶性淋巴结的血管类型。发现良性淋巴结（３０个）多在门部有一支和／或有小的分支；而恶性淋巴结（５０个）血流主要是外周型和／或中央血流型。这一特征，加上淋巴结形态及病史，有助于淋巴结良性及恶性病变的鉴别诊断     

Quantitative Assessment of Skin Stiffness Using Ultrasound Shear Wave Elastography in Systemic Sclerosis

This study was aimed at investigating the performance of ultrasound shear wave elastography (US-SWE) in the assessment of skin (the dermis) stiffness in patients with systemic sclerosis (SSc). The thickness and elastic modulus of the skin were measured using US-SWE at 6 sites in 60 SSc patients and 60 healthy volunteers: the bilateral middle fingers and forearms and the anterior chest and abdomen. To evaluate clinical scores, the measurements were also extended to 17 skin sites in 30 patients. The diagnostic performance of US-SWE in the differentiation of SSc from healthy skin was determined by receiver operating characteristic (ROC) curve analysis, and the reliability of the measurement was evaluated with intra- and inter-class correlation coefficients. The results of US-SWE were compared with modified Rodnan skin thickness scores. Our results indicated that (i) the elastic modulus values were significantly higher in SSc patients than in controls, with or without normalization by skin thickness; (ii) receiver operating characteristic analysis revealed normalized US-SWE cutoff values with a very high accuracy for right and left fingers (areas under the curve?=?0.974 and 0.949), followed by left forearm (0.841), anterior abdomen (0.797), right forearm (0.772) and anterior chest (0.726); (iii) the reliability of US-SWE measurements was good for all examined sites with intra-observer correlation coefficients of 0.845–0.996 and inter-observer correlation coefficients of 0.824–0.985; and (iv) total scores of skin involvement determined at 17 sites (modified Rodnan skin thickness scores) correlated with skin stiffness (r?=?0.832) and thickness (r?=?0.736). In conclusion, US-SWE is a quantitative method with high specificity, sensitivity and reliability in the detection of SSc involvement. This non-invasive, real-time and operator-independent imaging technique could be an ideal tool for the assessment of SSc disease.