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

Abstract

Objective. To investigate the difference in the nodal hilus evaluated by gray scale and power Doppler sonography. Methods. One hundred ninety-two patients with proven cervical lymphadenopathy were included in the study (metastases, n = 118; tuberculosis, n = 56; and lymphoma, n = 18). Lymph nodes were evaluated by gray scale sonography for the echogenic hilus and power Doppler sonography for hilar vascularity. Results. Hilar vascularity was found even though the lymph node did not show an echogenic hilus on gray scale sonography (metastases, 59%; tuberculosis, 66%; and lymphoma, 91%). Conclusions. Sonologists should be aware that gray scale and Doppler sonography show different aspects of the hilus, and the absence of the hilus on gray scale sonography does not necessarily imply an associated absence of hilar vascularity. Key words: gray scale sonography; power Doppler sonography; hilus; cervical nodes. he role of sonography in the evaluation of neck nodes is well established. Previously, sonography of lymph nodes involved only gray scale sonography, and evaluation of the nodal hilar architecture was an essential part of the examination. The absence of a hilus was usually considered an abnormality.1,2 However, to our knowledge, the sonographic literature has not addressed whether the absence of an echogenic hilus on gray scale sonography implies the absence of hilar vasculature. With power Doppler sonography (PDS), it is now possible to evaluate intranodal vasculature.In our experience, often in abnormal nodes the echogenic hilar architecture is absent on gray scale imaging (Fig. 1), but the hilar vessels are clearly shown on PDS (Fig. 2). Because this has not been emphasized in the literature, often sonologists have presumed that the absence of the echogenic hilus on gray scale sonography also implies the absence of hilar vasculature. We were therefore interested in documenting the appearance of hilar vessels so that sonologists would be aware of the differences in nodal hilar evaluation by gray scale sonography and PDS.

Gray Scale and Power Doppler Study of Biopsy‐Proven Kikuchi Disease

“…Most of the sonographic findings of Kikuchi disease can also be seen in other diseases causing cervical lymphadenopathy; thus, differential diagnosis may be very difficult. Normal hilar vascularity can also be seen in reactive hyperplasia and lymphoma 18 . However, reactive hyperplasia and lymphoma do not generally show increased perinodal echogenicity.…”

Preoperative Localization of Abnormal Parathyroid Glands

“…31,32 Acute inflammatory lymph nodes can easily be distinguished from the typical parathyroid Doppler color pattern, because internal linear vascular signals are observed at the lymph node hilum. 33 On the other hand, color Doppler US has a limited role when evaluating patients with Hashimoto's thyroiditis and concomitant enlarged lymph nodes that cannot be distinguished from avascular parathyroid lesions. Therefore, the diagnostic value of color Doppler US is limited in all cases in which flow is not significant in the suspect lesion, and no conclusion should be drawn about the nature of the mass examined.…”

Positive Predictive Value and Interobserver Variability of Preoperative Staging Sonography for Thyroid Carcinoma

“…The sonography criteria for LN metastases for N staging were as follows: absence of echogenic fatty hilum, a round shape (ratio of the long to the short axis, < 1.5), focal or diffuse hyperechogenicity compared with the adjacent muscle, microcalcifications, cystic change, and a chaotic or peripheral vascular pattern [11][12][13][14][15]. If any single one of these features was present, the LN underwent sonography-guided FNAB immediately after preoperative staging sonography, if possible.…”