Sonographic evaluation of cervical lymph nodes

OBJECTIVE: Sonography is a useful imaging tool in the evaluation of cervical lymph nodes. Gray-scale sonography and color and power Doppler sonography are commonly used in clinical practice. This article documents the common sonographic appearances of different causes of cervical lymphadenopathy. CONCLUSION: The sonographic appearances of normal nodes differ from those of abnormal nodes. Sonographic features that help to identify abnormal nodes include shape (round), absent hilus, intranodal necrosis, reticulation, calcification, matting, soft-tissue edema, and peripheral vascularity.     

An overview of neck node sonography

RATIONALE AND OBJECTIVES: Gray scale and power Doppler sonography are commonly used to evaluate cervical lymph nodes. This study was undertaken to identify which of the features used in ultrasound of cervical lymph nodes is readily applicable in routine clinical practice. METHODS: Two hundred and eight-six patients diagnosed with cervical lymphadenopathy were included in the study. The largest node in each patient was included in the study and the nature of the node was assessed by fine-needle aspiration cytology. Lymph nodes were assessed for their gray scale and Doppler sonographic features. RESULTS: Metastatic, lymphomatous, and tuberculous nodes were round (63-94%) and without echogenic hilus (57-91%). Sharp borders were found in metastatic and lymphomatous nodes (56-100%), but uncommon in tuberculosis (49%). Capsular or mixed vascularity is common in metastatic, lymphomatous, and tuberculous nodes but not found in reactive nodes. Except metastatic nodes from papillary carcinoma of the thyroid that showed low resistance, metastatic nodes had a higher vascular resistance than reactive nodes. Micronodular echo pattern is common in lymphomatous nodes. Hyperechogenicity and punctate calcification are typical features for metastatic nodes from papillary carcinoma of the thyroid. Intranodal cystic necrosis, adjacent soft tissue edema, matting and displaced hilar vascularity are common features in tuberculosis. CONCLUSIONS: Using gray scale and power Doppler sonography, metastatic, lymphomatous, and tuberculous nodes can be differentiated from reactive nodes. Metastatic nodes from papillary carcinoma, lymphoma, and tuberculosis can be identified. However, it is difficult to differentiate metastatic nodes from squamous cell carcinomas, nasopharyngeal carcinoma, and infraclavicular carcinomas, and differentiate metastatic nodes (nonthyroid primary) from tuberculous lymphadenitis.     

Differentiation of benign and malignant cervical lymph nodes: Value of B-mode and color Doppler sonography

Objective: To evaluate the efficacy of color Doppler sonography in detecting possible differences in blood flow patterns and B-mode sonographic characteristics between malignant and benign cervical lymph nodes. Patients and methods: During a period of 10 months, the palpable cervical lymph nodes of 39 patients were prospectively evaluated with B-mode and color Doppler sonography. The echogenity, contour, ratio of longitudinal diameter to the transverse diameter and the presence of a hilus were evaluated by B-mode sonography. Capsullary and intranodal arterial flow rates were measured and maximal systolic, end-diastolic, mid-systolic flow velocities with pulsatility, resistivity and acceleration indices were obtained. Final diagnosis was established by excisional biopsy (n:34) and clinical follow-up (n:5). Results: The lymph nodes in 20 cases were malignant and in 19 cases were benign. The B-mode contour characteristics and presence of a hilus in malignant and benign lymph nodes were statistically significant (P<0.05), but there were no significant differences between the ratio of longitudinal diameter to the transverse diameter (P>0.05), echogenity (P>0.05) and the diameters of lymph nodes (P>0.05). Flow patterns were obtained in 14 malignant (70%) and 10 benign (52.6%) cases. The maximal systolic, end diastolic, mid-systolic flow velocities and pulsatility, resistivity, acceleration indices did not differ statistically (P>0.05). Conclusion: In the differentiations of benign and malignant cervical lymph nodes, the B-mode and color Doppler sonography are limited methods and can not replace biopsy.     

Wertigkeit der signalverstärkten farbkodierten Duplexsonographie in der Beurteilung von reaktiv vergrößerten Lymphknoten

PURPOSE: This prospective study was performed to investigate characteristic sonomorphological features and vascularity of reactively enlarged lymph nodes. METHOD: We examined 40 patients with enlarged lymph nodes of the neck by Doppler sonography before and after administration of an ultrasound signal-enhancing agent. Peak flow velocity, pulsatility- and resistant indices were assessed. Lymph nodes were sonomorphologically classified into three groups: homogeneous parenchyma (1), a centrally located echogenoic line (2) and an echogenoic "hilus reflex" (3). The quantitative and qualitative criteria were compared to histological findings. RESULTS: A total of 15 lymph nodes appeared homogeneous. A centrally located echogenoic line was found in 17 (42.5%) nodes and echogenoic "hilus reflex" in 8 (20%). These sonomorphological patterns correlate to hilus fibrosis in the histological specimen. In 32.5% (13) of the nodes the analysis of vascularity was possible only after application of the galactose-based ultrasound signal enhancer. Quantitative analysis did not result in specific new aspects. CONCLUSIONS: Reactive lymph nodes show typical sonomorphological features. Administration of an ultrasound enhancer allows assessment of a characteristic nodal vascualrity.     

Contribution of doppler sonography blood flow information to the diagnosis of metastatic cervical nodes in patients with head and neck cancer: assessment in relation to anatomic levels of the neck

BACKGROUND AND PURPOSE: Although sonographic evaluation of cervical adenopathy by use of size criteria is effective, the sensitivity and specificity fall short of that required to make adequate judgments regarding neck dissection. Therefore, we tested whether the combined use of size criteria and Doppler sonographic findings would improve the predictive ability for metastatic cervical nodes. METHODS: We analyzed 338 histologically proved cervical lymph nodes (108 metastatic and 230 nonmetastatic) in 73 patients with head and neck cancer. The sonographic topography of the nodes was compared with dissected specimens, and their position in the neck was categorized into three levels (I, II, and III+IV). The diagnostic accuracy of sonography was evaluated by using the single criterion of short-axis diameter of the node or by the combined criteria of short-axis diameter and Doppler blood flow features (the absence or presence of normal hilar flow). RESULTS: As compared with the single criterion of short-axis nodal diameter, the combined criteria of nodal size and Doppler blood flow patterns increased the diagnostic accuracy of sonography at all levels in the neck. Accordingly, the best cut-off values were improved to 6, 7, and 5 mm for nodes at levels I, II, and III+IV, respectively. In addition, the combined criteria yielded high sensitivites (> or = 89%) and specificities (> or = 94%). CONCLUSION: Hilar blood flow information obtained by Doppler sonography significantly improves diagnostic accuracy for the detection of nodes metastatic from head and neck squamous cell carcinoma.     

Distribution of intranodal vessels in differentiating benign from metastatic neck nodes

AIM: Recent studies report high accuracy of power Doppler sonography in the differentiation of benign from malignant cervical lymphadenopathy. This study was undertaken to identify which of the parameters used in Doppler sonography of cervical lymph nodes is accurate and readily applicable in routine clinical practice. MATERIALS AND METHODS: We reviewed the power Doppler ultrasound examinations of 50 patients with cytologically proven metastatic nodes from nasopharyngeal carcinoma and 50 patients with proven reactive lymphadenopathy. All the examinations had been performed by an experienced sonologist, and intranodal vascular distribution and resistance were evaluated during real-time ultrasound. Twenty metastatic nodes and 40 reactive nodes were less than 10 mm in maximum transverse diameter. The vascular patterns of lymph nodes were classified into three categories: (1) hilar; (2) capsular; (3) hilar and capsular. The resistive index (RI) and pulsatility index (PI) were measured by spectral Doppler. RESULTS: Although metastatic nodes (RI, 0.81 +/- 0.11; PI, 1.89 +/- 0.89) tended to have higher intranodal vascular resistance than reactive nodes (RI, 0.65 +/- 0.08; PI, 1.07 +/- 0.26), there was considerable overlap of the resistance parameters between benign and malignant nodes. Most of the metastatic nodes showed the presence of capsular vascularity (capsular, 16%; capsular and hilar, 78%), whereas the majority of the reactive nodes showed hilar vascularity (98%), and the difference was significant. CONCLUSION: The distribution of intranodal vascularity appears to be more useful than RI or PI in differentiating benign from malignant cervical lymphadenopathy. It is also easier to evaluate the distribution and the results are therefore readily applicable in routine clinical practice.     

Power Doppler Sonography of Cervical Lymphadenopathy

AIMS: The supraclavicular region is a common site for tuberculous and metastatic nodes from infraclavicular carcinomas. Grey scale sonographic features differentiating the two have been previously described. However, as power Doppler sonography is now frequently used in the assessment of neck nodes, power Doppler features that may help to differentiate the two are discussed. MATERIALS AND METHODS: In 78 patients, power Doppler sonograms of nodes involved by metastases from infraclavicular carcinomas (n = 24) and tuberculosis (n = 54) were evaluated. The intranodal distribution of vessels and the intranodal vascular resistance of vessels was assessed and compared. In addition, the power Doppler features of metastatic nodes from infraclavicular carcinomas were compared with metastatic nodes from a head and neck primary (n = 38) such as nasopharyngeal carcinoma (NPC). RESULTS: Tuberculous nodes frequently demonstrated displaced hilar vascularity or avascularity and the intranodal vascular resistance was low. Metastatic nodes from infraclavicular primaries demonstrated capsular or mixed vascularity and their intranodal resistance was significantly (P < 0.05) higher. In general, metastatic nodes from infraclavicular primaries had a higher intranodal vascular resistance compared to metastatic nodes from NPC, but this was not statistically significant. CONCLUSION: In the supraclavicular region, the presence of displaced low resistance hilar vascularity or avascularity in nodes is suggestive of tuberculous nodes. Metastatic nodes from infraclavicular primaries have a capsular or mixed vascularity with high resistance.     

Sonography of neck lymph nodes. Part II: abnormal lymph nodes

Assessment of cervical lymph nodes is essential for patients with head and neck carcinomas, and ultrasound is a useful imaging technique. Sonographic features that help distinguish between the causes of neck lymphadenopathy, including grey scale and Doppler features, are discussed. In addition to the distribution and location of nodes, the useful grey-scale features are: size, shape, internal architecture, intranodal necrosis, absence of hilar structure and calcification. The useful Doppler features are: distribution of vascularity and intranodal resistance. Ancillary features such as oedema of soft tissue and nodal matting are particularly helpful to identify tuberculous nodes.     

Comparison of sonography and CT for differentiating benign from malignant cervical lymph nodes in patients with squamous cell carcinoma of the head and neck

OBJECTIVE: We compared the ability of sonography and CT to differentiate benign from malignant cervical lymph nodes in patients with squamous cell carcinoma of the head and neck. MATERIALS AND METHODS: We analyzed 209 cervical nodes (102 metastatic and 107 nonmetastatic) from 62 patients with head and neck cancer. These nodes were topographically correlated by node between images and surgical specimens, and accordingly between sonography and CT. RESULTS: The area under the receiver operating characteristic curve (A(z) value) for the overall impressions of metastatic or nonmetastatic nodes was significantly greater for sonography (power Doppler sonography plus gray-scale sonography, 0.97 +/- 0.005; gray-scale sonography, 0.95 +/- 0.004) than for CT (0.87 +/- 0.018). Receiver operating characteristic curve analysis also showed that the greater ability of sonography to depict the internal architecture of the nodes (A(z) value, 0.96 +/- 0.006) compared with CT (A(z) value, 0.81 +/- 0.027) significantly contributed to the better performance of sonography compared with CT in diagnosing metastatic nodes in the neck. On the other hand, size criterion (the short-axis diameter) was equally predictive in sonography and CT. The greater contributions of internal architectures relative to the size criterion of the node in the sonographic assessment for metastatic nodes were further evidenced by the findings that sonography provided higher sensitivity and specificity than CT did, whereas the cutoff points for the short-axis diameter in both tests were equivalent. CONCLUSION: Sonography performed significantly better than CT in depicting cervical metastatic nodes. Sonography could be a useful adjunct to CT in surveying cervical metastatic nodes.     

Change of sonographic findings on cervical lymph nodes before and after preoperative radiotherapy

The aim of this study was to assess the changes in the power Doppler sonographic findings in patients with oral cancer undergoing chemotherapy and radiotherapy. We performed US examinations on 187 cervical lymph nodes (71 metastatic and 116 reactive nodes) excised from 52 patients before and after preoperative therapy. On Power Doppler images, we calculated the vascular index (VI) and evaluated the vascular pattern. We also assessed the diagnostic power using receiver operating characteristic (ROC) curve analysis. Irradiation caused an increase of the VI and better visualization of the vessels within the lymph node in the reactive nodes; however, in the metastatic nodes, the VI was not significantly different between that before and after irradiation. When the reader observed the images before irradiation, the area under an ROC curve (Az values) observed by B-mode sonography were closely similar to those obtained by B-mode plus power Doppler sonography. With both images before and after irradiation, the Az value obtained by B-mode plus power Doppler sonography was higher than that by B-mode sonography alone. After irradiation, the enhanced Doppler signals contributed to a better visualization of the vessels and a better detection of any vascular abnormalities.     

Power Doppler sonography of cervical lymph nodes in patients with head and neck cancer.

PURPOSEThe purpose of this preliminary study was to evaluate the usefulness of power Doppler sonography in differentiating metastatic from nonmetastatic cervical lymph nodes in patients with cancer.METHODSHistologically proved metastatic (n = 71) and nonmetastatic (n = 220) lymph nodes were examined with power Doppler sonography in 77 patients with head and neck cancer. Power Doppler sonography was assessed for its ability to differentiate metastatic from nonmetastatic lymph nodes.RESULTSPower Doppler sonography showed characteristic features of parenchymal blood flow signal in 59 (83%) of the 71 metastatic lymph nodes. By contrast, only four (2%) of the 220 nonmetastatic nodes showed these power Doppler signals. In addition, power Doppler sonography showed high levels of sensitivity (83%) and specificity (98%) in depicting metastatic lymph nodes, which were superior to the values (66% sensitivity and 92% specificity) obtained by applying size criteria (transverse to longitudinal ratio). However, a combination of the two criteria (parenchymal color signal and transverse to longitudinal ratio) improved diagnostic accuracy to 92% sensitivity and 100% specificity.CONCLUSIONOur preliminary findings suggest that the power Doppler criteria of no hilar flow, peripheral parenchymal nodal flow, and a transverse to longitudinal ratio of more than 0.65 together constitute a powerful tool for depicting metastatic lymph nodes in patients with cancer.     

Current status of power Doppler and color Doppler sonography in the differential diagnosis of lymph node lesions

The use of Power Doppler sonography in nodal diseases provides an improvement of early and noninvasive diagnosis of regional metastatic involvement. By using Power Doppler sonography it is possible to characterize lymph nodes as reactively enlarged, metastases, malignant lymphoma, tuberculosis and to study cervical cysts. The high diagnostic accuracy is based on perfusion-characteristics of these lymph nodes. Reactive lymph nodes show increased central perfusion of the hilum, whereas metastases tend to show increased peripheral perfusion. Affected lymph nodes in patients with by malignant lymphoma are highly perfused in the center but also peripheral. Power Doppler sonography is still not able to discriminate small (<8 mm) nonnecrotic metastasis or micrometastases from reactive lymph nodes. The purpose of this paper is to provide a summary of the current status of power Doppler and Doppler sonography in the differential diagnosis of lymph nodes.     

Differential diagnosis of lymph node lesions. A semiquantitative approach with power Doppler sonography.

RATIONALE AND OBJECTIVES: To assess the value of power Doppler for distinguishing reactive from malignant lymph node disease. METHODS: In a prospective study, 48 untreated patients with palpable cervical lymph node enlargement (n = 211) underwent examination with power Doppler sonography. The perfusion sites were subdivided into three groups: central, peripheral, and hilar perfusion. In addition, the authors qualified the intensity of perfusion using a semiquantitative scale from 0 (no perfusion) to III (high perfusion). Finally, the overall perfused lymph node area was measured and the percentage of perfused nodal area was calculated. RESULTS: Power Doppler sonography showed perfusion in 183 of 211 lymph nodes. Histologic examination revealed 67 reactively enlarged lymph nodes, 72 metastases, and 44 lymphomas. Reactively enlarged lymph nodes showed characteristically intense hilar perfusion (82.1%), whereas nodal metastases exhibited mainly peripherally located flow (84.7%) of grade intensity I to III. Lymph nodes invaded by malignant lymphoma were highly perfused, displaying color signals in the center as well as in the nodal periphery (90.9%). CONCLUSIONS: The perfusion patterns of lymph nodes provide useful additional information in the differential diagnosis of cervical lymphadenopathy.     

Detection of occult metastatic lymph nodes in the neck with gray-scale and power Doppler US

Purpose: To determine the most accurate criterion for predicting malignancy of small cervical lymph nodes with gray-scale ultrasound (GSUS) and power Doppler ultrasound (PDUS).Material and Methods: Findings of 69 pathologically verified cervical nodes (38 benign, 31 malignant) in 57 patients without wide echogenic hilum on GSUS that measured less than 10 mm in minimal axial diameter were prospectively studied. Minimal and maximal axial diameters, ratios of minimal to maximal axial diameters, and presence or absence of calcification or necrosis of the nodes were assessed. On PDUS, vascularity in the node was classified into 4 pattern groups. A logistic model was used to evaluate the significant factors for predicting malignancy.Results: The logistic model revealed that the minimal axial diameter and vascularity patterns were the only significant factors for malignancy. Using the minimal axial diameter, a node larger than 8 mm showed the highest accuracy (73%) with 45% sensitivity and 93% specificity. Of the vascularity patterns, spotted or peripheral pattern had the highest accuracy (80%) with 61% sensitivity and 93% specificity. A combined criterion of the minimal axial diameter larger than 8 mm and spotted or peripheral pattern increased the accuracy to 82% and sensitivity to 77% but specificity decreased to 86%.Conclusion: A combined criterion of minimal axial diameter and vascular patterns was most accurate for diagnosing occult metastatic lymph nodes in the neck.     

Grey-scale and colour Doppler sonography in the evaluation of children with suspected bowel inflammation: correlation with colonoscopy and histological findings

AIM: To evaluate the correlation of grey-scale and colour Doppler sonography with colonoscopy and histology to detect bowel inflammation in children. MATERIAL AND METHODS: The records of 72 patients with suspected bowel inflammation were reviewed retrospectively. Patients were included in the study if sonography had been performed up to 30 days before colonoscopy. Grey-scale and colour Doppler sonography were used to evaluate bowel wall thickness and vascularity for the detection of distal bowel inflammation. Findings were correlated with colonoscopy and histological findings. The sensitivity and specificity of sonographic wall thickness to detect inflammation was determined. Spearman's coefficient (rs) was used to determine the correlation of Doppler findings with colonoscopy/histology. RESULTS: Sonograms of 372 bowel segments were evaluated and results were correlated with colonoscopy and histological findings of 352 segments. The sensitivity and specificity of sonographic bowel thickness to detect inflammation in the terminal ileum and the right colon were high; in the other segments, specificity was high but sensitivity was low. The correlation of Doppler sonography with colonoscopy and histology to detect inflammation in the terminal ileum was strong (rs: 0.84; p<0.001) and in the other segments, weak to moderate; when the interval between examinations was shorter than 10 days, the correlation was stronger in all segments. Of nine patients with abnormal small bowel sonograms but normal colonoscopies, three had Crohn's disease. CONCLUSION: Sensitivity and specificity of grey-scale sonography to detect inflammation in the terminal ileum and the right colon were high, and the correlation of Doppler with colonoscopy and histology was very strong in the same segments.     

Hemangioendothelioma of the parotid gland in infants: sonography and correlative MR imaging

BACKGROUND AND PURPOSE: Hemangioendothelioma is the most common parotid gland tumor of childhood, and is diagnosed on clinical grounds, supported by imaging findings. Previous work has suggested that MR is the best imaging technique for assessment of parotid hemangioendothelioma. Demonstration of a reliable sonographic appearance would reduce the need for MR imaging in infants with this lesion. METHODS: We performed high-frequency sonography (including color Doppler and power Doppler imaging) in three patients, each with a diagnosis of parotid hemangioendothelioma confirmed by clinical follow-up. Two patients were also examined with MR imaging and labeled red cell scintigraphy. RESULTS: All sonographic studies showed a homogeneous mass enlarging and replacing most or all of the visualized parotid gland, with a lobular internal structure, fine echogenic internal septations, and a mildly lobulated contour. Color Doppler and power Doppler imaging showed extremely high vascularity within the mass. Correlative MR images in two infants showed a well-defined lesion with uniform intense contrast enhancement. Labeled red cell scintigraphy showed a well-defined area of intense activity. CONCLUSION: In the presence of a typical clinical history, sonography and clinical follow-up alone may prove to be sufficient for safe management of parotid hemangioendothelioma. MR imaging or labeled red cell scintigraphy may only be required if the sonographic features are atypical. These findings require confirmation in a larger series of patients.     

颈部淋巴结超声特征的计算机提取及相关性评价

目的：评价计算机所提取的颈部淋巴结超声特征与医生的经验判断的相关性，以预测能否实现颈部淋巴结超声图像计算机辅助诊断。材料和方法：利用彩色多普勒超声观察43例患者的106个淋巴结的超声特征，包括大小、形态、边界、纵横比、淋巴门、皮髓质分布及比例、淋巴结内部回声、血流分布等。将超声医生判断分级的结果与计算机提取的淋巴结超声特征的参数定量结果作相关分析。结果：相关性较好的参数为NRL过零率（r=0．304，P=0．002）、凸包深度（r=0．32，P=0．001）、长／短径比率（r=-0．318，P=0．001）、血流像素点数（r=0．702，P〈0．001）、投影轮廓点分布的熵（r=0．719，P〈0．001）。结论：通过对颈部淋巴结超声图像提取量化特征参数，初步实现了颈部淋巴结良、恶性疾病的计算机辅助诊断。     

Sonography of neck lymph nodes. Part I: normal lymph nodes

Grey scale and power Doppler sonography play an important role in assessment of cervical lymphadenopathy. However, before examination of pathological nodes, a clear understanding of the anatomy of cervical nodes, scanning technique and sonographic appearances of normal cervical nodes is essential. This article reviews these topics in order to provide a baseline for sonographic examination of cervical lymphadenopathy.     

彩色多普勒超声评价肿瘤血管在甲状腺结节诊断中的应用

目的:研究甲状腺结节内肿瘤血管及颈部转移淋巴结的彩色多普勒超声表现。方法:分析42例甲状腺癌和46例甲状腺良性结节的血管形态及血流动力学特征。结果:甲状腺癌及甲状腺癌复发病例中,69.0%(29/42)血流为Alder2级或3级,38.1%(16/42)可见穿入性或分支异常的血管,71.4%(30/42)血流为高阻力型(RI>0.7)。甲状腺良性结节中,上述表现发生率分别为39.1%(18/46)、6.5%(3/46)、10.9%(5/46)。23例甲状腺癌可见颈部转移性淋巴结,其中82.6%(19/23)的血流形态表现为紊乱分布的包膜下血流。结论:甲状腺癌肿瘤血管的发现及颈部淋巴结的血流表现有助于甲状腺癌的正确诊断。     

Multivariate feature analysis of sonographic findings of metastatic cervical lymph nodes: contribution of blood flow features revealed by power Doppler sonography for predicting metastasis

BACKGROUND AND PURPOSE: Sonographic criteria of the lymph node have been found to be good indicators for metastatic lymph nodes. We determined which sonographic features are most predictive of metastasis in cervical lymph nodes among patients with head and neck cancer. METHODS: Gray-scale and power Doppler sonograms were retrospectively analyzed in 133 cervical lymph nodes (57 metastatic and 76 reactive nodes) from 52 patients with head and neck cancer. The gray-scale sonographic features of the presence or absence of hilar echoes, parenchymal echogenicity, and short and long axis lengths as well as the power Doppler features of normal hilar flow and abnormal parenchymal flow were evaluated. Univariate and multivariate logistic regression analyses were conducted to determine the relative value of each sonographic feature. RESULTS: At univariate analysis, all sonographic features assessed were found to be important. Multivariate analysis, however, suggested that the presence or absence of hilar echoes, increases in short axis length, and the presence of normal hilar flow were the only sonographic features that were predictive of reactive (presence of hilar echoes and hilar flow) and metastatic (increases in short axis length) lymph nodes. Although multivariate analysis did not indicate any significant contribution of the color-flow criteria for predicting metastatic nodes, the color-flow criteria appeared to improve the overall diagnostic accuracy for the less experienced observer. CONCLUSION: The sonographic criteria most predictive of metastatic cervical lymph nodes were absent hilar echoes and increases in short axis length, as assessed by logistic regression analysis. Compared with these gray-scale criteria, color-flow criteria had fewer predictive advantages.