Abstract

Background: Cervical lymph nodes are also common sites of involvement of lymphoma; tuberculous (TB) lymphadenitis; and other benign and malignant lymphadenitis. It is essential to evaluate the cervical lymph nodes in various head and neck diseases. The role of gray scale sonography of neck lymph nodes is well established and it is widely utilizes for the evaluation of the number, size, site, shape, borders, matting, adjacent soft-tissue edema, and internal architectures of cervical lymph nodes. The advance research in power Doppler sonography (PDS) has further increased the utilization of ultrasonographic (USG) evaluation of cervical lymph nodes for diagnostic purpose. Objectives: The aim of this study is to evaluate the importance of gray scale, Doppler and spectral waveform study in differentiation of benign and malignant neck lymphadenopathy and to find out sensitivity and specificity of gray scale, Doppler and spectral waveform study in differentiation of benign and malignant neck lymphadenopathy.
Materials and Methods: Patients were chosen from the outpatient department and from admissions in wards of otorhynolaryngology and surgery department. Patients with neck swelling are screened with USG. If USG shows the enlarged lymphnode, then detailed study was performed by gray scale, color, power Doppler, and by spectral waveform analysis. For differentiation from metastatic lymph nodes criteria given by Ahuja was utilized.
Results: A total of 100 enlarged neck lymph nodes studied in 75 patients with neck lymphadenopathy. Metastatic lymph node enlargement was 38.67%, lymphoma 6.67%, TB 28%, and reactive 26.66%. Moreover male: female ratio was 2.6:1. The percentage of L/S ratio <2 for metastatic, lymphoma, and TB are 68%, 78%, and 72%, respectively While 60% of reactive nodes shows L/S ratio 2 or >2. 76% metastatic, 56% lymphoma, 72% of TB lymphadenopathy had the loss of echogenic hilum, whereas 76% reactive nodes preserved echogenic hilum. The mean resistive index (RI) and pulsatality index (PI) value of metastatic nodes 0.81, 1.87, lymphomatous nodes 0.8, 1.36; TB nodes 0.67, 1.17 and for reactive nodes 0.61, 1.05, respectively. Sensitivity of RI for malignant lymph nodes is 39%, specificity is 84%. While the sensitivity of PI for malignant lymph nodes is 44%, specificity is 87%. Conclusion: Gray scale and PDS helps in differentiation of metastatic, lymphomatous, and TB nodes from reactive nodes. The sonographic criteria most predictive of metastatic cervical lymph nodes were absent hilar echoes, increases in short axis length, necrosis, peripheral, or mixed vascularity. However, there is similarity in appearance to some extent between TB nodes, benign reactive neck nodes, and metastatic nodes. And thus, histological analysis is still utilized for a definitive diagnosis.