Review of ultrasonography of malignant neck nodes: greyscale, Doppler, contrast enhancement and elastography

Abstract

Assessment of neck lymph nodes is essential in patients with head and neck cancers for predicting the patient's prognosis and selecting the appropriate treatment. Ultrasonography is a useful imaging tool in the assessment of neck lymph nodes. Greyscale ultrasonography assesses the size, distribution, and internal architecture of lymph nodes. Doppler ultrasonography evaluates the intranodal vascular pattern and resistance of lymph nodes. Contrast-enhanced ultrasonography provides information on lymph node parenchymal perfusion. Elastography allows qualitative and quantitative assessment of lymph node stiffness. This article reviews the value of greyscale, Doppler and contrast-enhanced ultrasonography as well as elastography in the assessment of malignant nodes in the neck.

Figure 1

Transverse greyscale sonogram in a patient with carcinoma of the tongue shows a hypoechoic metastatic lymph node in the internal jugular chain. The lymph node is round in shape with well-defined borders and without an echogenic hilus (arrows).

Figure 2

Longitudinal greyscale sonogram in a patient with carcinoma of the tongue shows a hypoechoic metastatic lymph node in the submandibular region. The lymph node is well defined and demonstrates eccentric cortical hypertrophy, which is related to focal tumour infiltration within the lymph node (arrows). Arrowheads indicate the intranodal echogenic hilus.

Figure 3

Transverse greyscale sonogram in a patient with carcinoma of the larynx shows a hypoechoic metastatic lymph node in the internal jugular chain. The lymph node is round in shape with absence of echogenic hilus. The borders of the lymph node are ill defined indicating extracapsular spread (arrows). Note the tumour invasion into the adjacent soft tissues (arrowheads).

Figure 4

Longitudinal greyscale sonogram in a patient with tuberculous lymphadenitis shows a hypoechoic necrotic tuberculous node with ill-defined borders and absence of echogenic hilus (arrows).

Figure 5

Transverse greyscale sonogram in a patient with reactive lymphadenitis shows a reactive lymph node in the submandibular region (arrows). The lymph node is hypoechoic, oval shaped, with an echogenic hilus (arrowheads). Note the echogenic hilus is continuous with adjacent fat.

Figure 6

Transverse greyscale sonogram in a patient with papillary carcinoma of the thyroid shows a metastatic lymph node in the internal jugular chain (arrows). The lymph node is round, well defined and hyperechoic compared with the adjacent muscle. Note the intranodal calcification, which is echogenic and punctuate (white arrowhead). The black arrowheads indicate the common carotid artery.

Figure 7

Transverse greyscale sonogram in a patient with non-Hodgkin lymphoma shows multiple lymphomatous nodes in the internal jugular chain. The lymph nodes are well defined, hypoechoic with intranodal reticulation (arrowheads).

Figure 8

Transverse greyscale sonogram in a patient with carcinoma of the larynx shows multiple hypoechoic metastatic lymph nodes in the internal jugular chain (arrows). The lymph nodes are round in shape with intranodal cystic necrosis (arrowheads), commonly seen in metastatic nodes from squamous cell carcinoma.

Figure 9

Transverse power Doppler sonogram in a patient with lung carcinoma shows multiple metastatic lymph nodes in the supraclavicular fossa. The lymph nodes are round in shape with peripheral vascularity (arrowheads).

Figure 10

Longitudinal power Doppler sonogram in a patient with non-Hodgkin lymphoma shows a hypoechoic lymphomatous node in the submandibular region. The lymph node is oval in shape with both peripheral (arrowheads) and hilar (arrow) vascularity.

Figure 11

Spectral Doppler sonogram in a patient with carcinoma of the pharynx shows measurement of the resistive index (RI) and pulsatility index (PI) as well as the peak systolic velocity (PSV) and end diastolic velocity (EDV) of a metastatic lymph node in the internal jugular chain. The measurements are obtained from three consecutive waveforms.

Figure 12

Longitudinal greyscale sonogram (left image) and strain elastogram (right image) in a patient with reactive lymphadenitis show a reactive lymph node in the internal jugular chain (arrows). In the elastogram, the lymph node is predominantly colour coded as green and blue, which indicates the lymph node is soft.

Figure 13

Longitudinal greyscale sonogram (left image) and strain elastogram (right image) in a patient with carcinoma of the pharynx shows a metastatic lymph node in the internal jugular chain (arrows). In the elastogram, the lymph node is predominantly colour coded as red, which indicates the lymph node is hard.

Figure 14

Transverse shear wave elastogram in a patient with reactive lymphadenitis shows a reactive lymph node in the submandibular region. The lymph node has relatively lower stiffness values compared with the metastatic lymph node in Fig. 15. The large circle measures the overall stiffness of the lymph node, and the small circle measures a focal area within the node.

Figure 15

Transverse shear wave elastogram in a patient with carcinoma of the larynx shows a metastatic lymph node in the internal jugular chain. The lymph node has relatively higher stiffness values compared with the reactive lymph node in Fig. 14. The large circle measures the overall stiffness of the lymph node, and the small circle measures the relatively harder area within the node.