Ultrasonic viscoelastic imaging: a tool for parotid gland tumor differentiation.

OBJECTIVES

To evaluate the value of viscoelastic parameters in the differential diagnosis of parotid gland tumors.

MATERIALS AND

METHODS

A prospective study was conducted on 80 patients with parotid gland tumors who underwent viscoelastic ultrasound examination from September 2024 to April 2025. Patients were divided into four groups: pleomorphic adenoma (PA), warthin tumor (WT), benign tumor (BT), and malignant tumor (MT). Regions of interest (ROI) were delineated within the tumor and a 2 mm surrounding area to measure quantitative parameters, including shear wave elastography (SWE), viscous, dispersion, and strain elastography (SE) parameters. Statistical analysis of the four tumor parameters and qualitative assessment of viscoelasticity maps were performed. The diagnostic performance of each variable in classifying parotid gland tumors was assessed by comparing the area under the curve (AUC).

RESULTS

Parameters such as E-A-mean, Vi-A-max, and Disp-A-mean showed statistically significant differences between PA and WT. Dispersion parameters, including Disp-A-mean, Disp-A-max, and Disp-A-SD, were statistically significant in distinguishing BT from MT and WT from MT. Disp-A-mean had the best diagnostic value, with an optimal threshold of 4.70 m/s/kHz for PA and WT, and 7.08 m/s/kHz for BT and MT, as well as WT and MT. The proportion of Non-Edge Distribution of high dispersion values in the MT group, as shown by the dispersion heatmap, was significantly higher (75%, 9/12) than that in the BT group (14.1%, 10/68) (p < 0.001).

CONCLUSION

SWE parameters and the Viscous parameter Vi-A-max are useful in differentiating PA from WT. Dispersion parameters can effectively distinguish between PA and WT, WT and MT, and BT and MT. The distribution of the dispersion coefficient can also aid in the differential diagnosis of BT and MT.

KEY POINTS: QuestionWhat is the role of viscoelastic imaging in differentiating parotid gland tumors? FindingsDispersion parameters can effectively distinguish parotid gland tumors. The distribution of the dispersion coefficient can also aid in the differential diagnosis of BT and MT. Clinical relevanceEffective preoperative differentiation of BT and MT aids in predicting disease progression, selecting surgical options, and assessing prognosis.