RESUMEN
Objective To investigate the impact of different ROI and modulus of elasticity in shear wave elastography (SWE) for diagnosis of benign and malignant cervical lymph nodes. Methods Totally 143 enlarged cervical lymph nodes confirmed by puncture biopsy or surgical pathology were examined with routine ultrasound and SWE before operation. Three different ROI, including the small circular ROI (ROI-1) with diameter 2 mm, the maximum circle ROI (ROI-2) not exceeding the edge of the lymph node, and the manual delineation of the entire lymph node-marginal ROI (ROI-3) were used, all containing the hardest region of lymph nodes. The maximum elastic value (Emax), the mean elastic value (Emean) and the elastic standard deviation (SD) were measured and compared, respectively. ROC curve was constructed to obtain the AUC of each elasticity value for the diagnosis of benign and malignant lymph nodes in the neck. Results Emax, Emean and SD measured with 3 ROI in malignant lymph nodes were higher than those in benign lymph nodes (all P0.05), but there was significant difference of Emean and SD (both P0.05). AUC of Emean measured with ROI-1 was higher than those of ROI-2 and ROI-3 (both P0.05). Conclusion SWE could differentiate benign and malignant cervical lymph nodes, but its diagnostic efficacy varies with the choice of ROI and modulus of elasticity. When selecting a smaller ROI, it is recommended to use Emax and Emean, while Emax and SD are recommended when larger ROI is selected.