Ultrasound of neck lymph nodes: How to do it and how do they look?

To Drain or not to Drain? Point-of-care Ultrasound to Investigate an Axillary Mass: Case Report

Introduction: Point-of-care ultrasound (POCUS) has great sensitivity in the diagnosis of abscesses and swollen lymph nodes. Many studies outline the characteristics that distinguish abscesses from lymph nodes on POCUS. Case Report: We present a case from the emergency department in which a patient presented with a potential abscess but was found to have a malignant lymph node on imaging. Conclusion: Point-of-care ultrasound can be used to differentiate an abscess from a swollen lymph node. Abscesses are generally anechoic or hypoechoic with septae, sediment or gas contents, and they lack internal vascularity. Benign lymph nodes are echogenic with hypoechoic cortex with hilar vascularity.

Point-of-Care Ultrasound for Evaluating Lymphadenopathy in the Pediatric Emergency Department: Case Series and Review of Literature

BACKGROUND

Children present to the pediatric emergency department (ED) with enlarged lymph nodes due to a broad spectrum of conditions ranging from benign causes like reactive lymph nodes to adverse conditions like malignancy. Identifying sonographic features typical of infection, inflammation, and neoplasms will help assist clinicians in deciding the disposition of the patients from the ED. Point-of-care ultrasound has become an essential adjunct for diagnostic assessment in pediatric emergency medicine. The wider accessibility of ultrasound along with greater resolution using high-frequency probes places this noninvasive, nonradiation-based bedside examination, an ideal tool for real-time examination of the lymph nodes in the EDs.

CASE SERIES

We present a series of cases in which the point-of-care ultrasound examination proved valuable in the timely diagnosis and expedited care of lymph node pathologies secondary to reactive, infectious, and malignant processes. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Point-of-care ultrasound will facilitate diagnosis in children with lymph node swelling and should be considered in children of all ages. While assessing the lymph node pathology at the bedside, describe the shape, size, internal echotexture, borders, vascularity, and the pattern of the perinodal soft tissue to differentiate between a normal, reactive, infectious, inflammatory, or malignant underlying pathology.

Diagnostic performances of superb microvascular imaging, shear wave elastography and shape index in pediatric lymph nodes categorization: a comparative study

OBJECTIVE

To determine the diagnostic utility of a vascularity index via superb microvascular imaging in lymph nodes of children with malignant lymphoma and acute lymphadenitis compared to normal lymph nodes.

METHODS

We performed a retrospective study for multiparametric lymph node (LN) evaluation. Malignant lymphoma diagnosed via histopathological examination and lymph nodes receiving an acute lymphadenitis diagnosis based on clinical and laboratory findings constituted the study subgroups. We calculated a shape index [SI (percent of shortest to longest diameter)] using grayscale ultrasonography and elasticity and velocity values via shear wave elastography (SWE) as well as a vascularity index (VI) using superb microvascular imaging (SMI) for comparison with normal lymph nodes.

RESULTS

45 lymph nodes diagnosed with malignant lymphoma, 72 lymph nodes diagnosed with acute lymphadenitis and 146 normal lymph nodes were evaluated. For differentiating lymphoma from normal lymph nodes, vascularity index cut-off values higher than 15% represented a diagnostic accuracy of 95%; cut-off elasticity values higher than 17 kPa exhibited a diagnostic accuracy of 99%. Optimal VI, elasticity, velocity and SI cut-off values in differentiating lymphoma from lymphadenitis were 15%, 17 kPa, 2.45 m sn^-1 (p < 0.001) and 65% (p < 0.002) with calculated diagnostic accuracies of 83, 87, 88 and 68%, respectively.

CONCLUSION

Vascularity index values obtained via superb microvascular imaging and SWE would be reasonably useful in differentiating malignant lymphoma and acute lymphadenitis from normal LNs. SWE would be more efficient in distinguishing malignant lymph nodes from acute lymphadenitis compared with superb microvascular imaging. Advances in knowledge: Vascularity index by superb microvascular imaging would be a novel Doppler parameter in differentiating both lymphoma from lymphadenitis and also lymphadenitis from normal lymph nodes.

Ultrasonographic Appearances of Cervical Lymph Nodes in Healthy Turkish Adults Subpopulation: Preliminary Study

Objectives:

The aim of the study was to assess whether there was any relation between age, gender and body mass index (BMI) and nodal forms and vascular type in healthy Turkish adults.

Study Design:

Three neck areas in 25 wholesome patients who were aged from 21 to 58 years, were assessed by gray-scale and color doppler ultrasonography. Ultrasonographic examinations were performed using an ALOKA Prosound Alpha 6 (Hitachi Aloka Medical Systems, Tokyo, Japan) and the images were obtained with a 7.2 MHz linear array transducer. Hajek’s categorization of cervical lymph nodes for sonographic analysis was used. The ultrasonographic characteristics like size, shape, short axis/long axis ratio (S/L), hilum were evaluated. Ultrasonographic examinations of upper cervical, submandibular and submental lymph nodes were carried out and recorded.

Results:

The mean age of patients was 31.84±12.80 years. The ratios of lymph nodes with avascular pattern were 96% for the upper cervical lymph area, 92% for the submandibular area and 96% for the submental area. The lowest and highest ratios of short to long axis diameter (S/L) were calculated as 0.18 and 0.66 in all areas. Most normal nodes in the study were oval with an S/L ratio of less than 0.5.

Conclusion:

Normal cervical lymph nodes are oval, with an unsharp border and an echogenic hilum but no relation between the age, gender and BMI. Also ultrasonography is an applicable imaging modality for the examination of cervical lymph nodes. However, the deficiency in the number of patients might not allow to generalise our findings to the general populations.

Chapter 5 Ultrasound Characteristics of Benign vs Malignant Cervical Lymph Nodes

With approximately 800 lymph nodes in the body, and more than one-third found within the head and neck, lymph nodes are a common site for neck pathology. Differentiation between benign and malignant lymph nodes is critical in accurate prognosis; similarly, treatment hinges on accurate identification of the etiology of the pathologic process. Key gray-scale and color Doppler ultrasound criteria can help accurately distinguish between benign and malignant lymph nodes.

Use of high frequency ultrasound to monitor cervical lymph node alterations in mice

Cervical lymph node evaluation by clinical ultrasound is a non-invasive procedure used in diagnosing nodal status, and when combined with fine-needle aspiration cytology (FNAC), provides an effective method to assess nodal pathologies. Development of high-frequency ultrasound (HF US) allows real-time monitoring of lymph node alterations in animal models. While HF US is frequently used in animal models of tumor biology, use of HF US for studying cervical lymph nodes alterations associated with murine models of head and neck cancer, or any other model of lymphadenopathy, is lacking. Here we utilize HF US to monitor cervical lymph nodes changes in mice following exposure to the oral cancer-inducing carcinogen 4-nitroquinoline-1-oxide (4-NQO) and in mice with systemic autoimmunity. 4-NQO induces tumors within the mouse oral cavity as early as 19 wks that recapitulate HNSCC. Monitoring of cervical (mandibular) lymph nodes by gray scale and power Doppler sonography revealed changes in lymph node size eight weeks after 4-NQO treatment, prior to tumor formation. 4-NQO causes changes in cervical node blood flow resulting from oral tumor progression. Histological evaluation indicated that the early 4-NQO induced changes in lymph node volume were due to specific hyperproliferation of T-cell enriched zones in the paracortex. We also show that HF US can be used to perform image-guided fine needle aspirate (FNA) biopsies on mice with enlarged mandibular lymph nodes due to genetic mutation of Fas ligand (Fasl). Collectively these studies indicate that HF US is an effective technique for the non-invasive study of cervical lymph node alterations in live mouse models of oral cancer and other mouse models containing cervical lymphadenopathy.

Scanning the Post-Thyroidectomy Neck: Appearance and Technique

Thyroid cancer is the most common type of endocrine cancer. In 2009, there were approximately 37,200 cases newly diagnosed. Sonography is becoming the modality of choice to evaluate the neck preoperatively and postoperatively. Accurate scanning and evaluation is essential for proper diagnosis, surgical approach, and staging.

Integration of single-fiber reflectance spectroscopy into ultrasound-guided endoscopic lung cancer staging of mediastinal lymph nodes

We describe the incorporation of a single-fiber reflectance spectroscopy probe into the endoscopic ultrasound fine-needle aspiration (EUS-FNA) procedure utilized for lung cancer staging. A mathematical model is developed to extract information about the physiological and morphological properties of lymph tissue from single-fiber reflectance spectra, e.g., microvascular saturation, blood volume fraction, bilirubin concentration, average vessel diameter, and Mie slope. Model analysis of data from a clinical pilot study shows that the single-fiber reflectance measurement is capable of detecting differences in the physiology between normal and metastatic lymph nodes. Moreover, the clinical data show that probe manipulation within the lymph node can perturb the in vivo environment, a concern that must be carefully considered when developing a sampling strategy. The data show the feasibility of this novel technique; however, the potential clinical utility has yet to be determined.