Michael Ying

Ultrasound of malignant cervical lymph nodes

Abstract Malignant lymph nodes in the neck include metastases and lymphoma. Cervical nodal metastases are common in patients with head and neck cancers, and their assessment is important as it affects treatment planning and prognosis. Neck nodes are also a common site of lymphomatous involvement and an accurate diagnosis is essential as its treatment differs from other causes of neck lymphadenopathy. On ultrasound, grey scale sonography helps to evaluate nodal morphology, whilst power Doppler sonography is used to assess the vascular pattern. Grey scale sonographic features that help to identify metastatic and lymphomatous lymph nodes include size, shape and internal architecture (loss of hilar architecture, presence of intranodal necrosis and calcification). Soft tissue oedema and nodal matting are additional grey scale features seen in tuberculous nodes or in nodes that have been previously irradiated. Power Doppler sonography evaluates the vascular pattern of nodes and helps to identify the malignant nodes. In addition, serial monitoring of nodal size and vascularity are useful features in the assessment of treatment response.

An overview of neck node sonography

Ahuja A, Ying M. An overview of neck node sonography. Invest Radiol 2002;37:333–342. 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.

SONOGRAPHIC EVALUATION OF THE SIZE OF ACHILLES TENDON: THE EFFECT OF EXERCISE AND DOMINANCE OF THE ANKLE

This study was undertaken to measure and compare the thickness and cross-sectional area of the Achilles tendon between frequent- and infrequent-exercise subjects, and between the dominant and nondominant ankles in an asymptomatic Chinese population. Interobserver variability in the measurement of the size of Achilles tendon was also evaluated. High-resolution ultrasound (US) examination of Achilles tendons was performed in 40 healthy subjects (20 who frequently exercised, had exercise at least 3 days per week and at least 2 h per session; and 20 who infrequently exercised); their age range was 19 to 25 years. The thickness and cross-sectional area of the Achilles tendons were measured in a transverse scan at the level of medial malleolus. For each subject, the Achilles tendons were measured by five operators to evaluate the interobserver variability in the measurements. The mean thickness and cross-sectional areas of the Achilles tendon in a healthy Chinese population are 5.23 mm(2) and 56.91 mm(2)(2), respectively. The mean thickness of the Achilles tendon of frequent-exercise subjects (dominant ankle 5.43 mm, nondominant ankle 5.38 mm) was significantly greater than that of infrequent-exercise subjects (dominant ankle 5.08 mm, nondominant ankle 5.04 mm) (p < 0.05). The cross-sectional area of the tendons was also larger in frequent-exercise subjects but, whereas a significant result was found in dominant ankles (frequent-exercise subjects 60.46 mm(2)(2), infrequent-exercise subjects 54.71 mm(2)(2)) (p < 0.05), this was not the case for the nondominant ankles (frequent-exercise subjects 57.09 mm(2)(2), infrequent-exercise subjects 55.4 mm(2)(2)) (p > 0.05). In both frequent- and infrequent-exercise subjects, there was no significant difference in the mean thickness and cross-sectional area of Achilles tendon between dominant and nondominant ankles (p > 0.05). There was a high reproducibility in the sonographic measurement of the thickness (68%) and cross-sectional area (81%) of Achilles tendons. Results suggested that exercise would cause increase in the thickness and cross-sectional area of Achilles tendon. Interobserver variability is not significant in the sonographic measurement of Achilles tendons.

Diagnostic accuracy of sonographic criteria for evaluation of cervical lymphadenopathy.

Although ultrasonographic criteria for abnormal nodes are used routinely in the evaluation of cervical lymphadenopathy, the diagnostic accuracy of these criteria in different areas has not been documented. This study evaluated 977 normal cervical nodes from 80 normal subjects and 1419 abnormal cervical nodes from 277 patients with proven cervical lymphadenopathy. The diagnostic accuracy (sensitivity, specificity, positive predictive value, negative predictive value, and accuracy) of size, shape (short axis to long axis ratio), echogenic hilus, and nodal border for regional lymph nodes are evaluated and discussed.

Cervical lymphadenopathy: Sonographic differentiation between tuberculous nodes and nodal metastases from non–head and neck carcinomas

Clinical examination alone cannot differentiate between cervical tuberculous lymphadenitis and cervical nodal metastases from non–head and neck (NHN) carcinomas because the distributions of involved lymph nodes are similar. We evaluated the sonographic features of cervical lymph nodes that could be used to differentiate between the 2 categories of nodes.

A practical approach to ultrasound of cervical lymph nodes

Although the role of high resolution ultrasound (US) in evaluating cervical nodes is well established, it is often combined with fine needle aspiration cytology (FNAC). As a result, US appearances that help in distinguishing the various causes of cervical adenopathy are often overlooked and not emphasized. The aim of this study is to re-emphasize to the sonologist the US clues that may help in differentiating the aetiology of abnormal cervical nodes. We, therefore, present the spectrum of US appearances of lymph nodes. One hundred and forty patients (702 abnormal nodes) with known pathology were compared with 100 normal subjects (1211 nodes). After identifying an abnormal nodes, US features that further help in distinguishing between the various pathologies are the distribution of lymphadenopathy, echogenicity, calcification, distal enhancement, intranodal cystic necrosis, matting and soft tissue oedema.

The use of sonography in differentiating cervical lymphomatous lymph nodes from cervical metastatic lymph nodes

Lymphoma and metastases are common causes of cervical lymphadenopathy. Clinical examination alone is unable to differentiate the two. Ultrasound (US) with its high sensitivity and specificity when combined with a find needle aspiration cytology (FNAC) is therefore the ideal initial investigation. We present the spectrum of findings in 19 patients with non Hodgkins lymphoma (NHL), 15 patients with pharyngeal, laryngeal and oesophageal (PLO) carcinomas, 22 patients with oral cavity tumours and 12 patients with infraclavicular carcinomas. The US features found consistently useful in differentiating NHL from other metastases were the distribution of the nodes, distal enhancement and lack of intranodal necrosis. Other US features of abnormal nodes helped identify abnormality but did not help in differentiation.

Lymph node hilus: gray scale and power Doppler sonography of cervical nodes.

To investigate the difference in the nodal hilus evaluated by gray scale and power Doppler sonography.

Sonographic measurement of achilles tendons in asymptomatic subjects: variation with age, body height, and dominance of ankle.

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.

Sonographic evaluation of cervical lymphadenopathy: Is power doppler sonography routinely indicated?

Routine sonographic examination of neck nodes now includes both grey-scale and Doppler sonography. Although the addition of Doppler sonography to the well-established practice of grey-scale sonography increases the amount of information obtained by sonography, it also increases the examination time, particularly if spectral Doppler and estimation of vascular resistance is performed. This study was, therefore, undertaken to evaluate whether Doppler sonography is routinely indicated in every case or its use should be limited to those cases where grey-scale sonography is equivocal. We evaluated the grey-scale and power Doppler sonograms of 101 fine-needle aspiration cytology (FNAC)-proven metastatic nodes and 72 FNAC-proven nonmetastatic nodes. All lymph nodes were evaluated with grey-scale and power Doppler sonography. The shape, echogenicity, internal architecture, vascular distribution and vascular resistance of the lymph nodes were evaluated. Grey-scale sonographic features evaluated in this study had a high sensitivity (95%) and specificity (83%) in classifying metastatic and nonmetastatic nodes. Metastatic and nonmetastatic lymph nodes that could not be classified by grey-scale sonography demonstrated Doppler features that helped in their correct identification. Power Doppler sonography is not necessary for every case in routine clinical practice, but is essential and useful in patients where grey-scale sonography is equivocal. In this study, power Doppler sonography aided in the diagnosis in 5% and 17% of patients with metastatic and nonmetastatic nodes, respectively.