Usefulness of a Novel Ultrasonographic Classification Based on Anechoic Area Patterns for Differentiating Warthin Tumors from Pleomorphic Adenomas of the Parotid Gland

Sonography of Salivary Gland Tumors and Disorders

Diseases of the salivary glands are as common as they are diverse and can have different causes. Clinicians can differentiate salivary gland changes based on chronic systemic diseases, congenital and vascular malformations, and benign and malignant tumors. Acute infectious pathologies can also arise as a result of obstructive pathologies. A large number of diseases with similar clinical presentations have to be differentiated. Due to the improved resolution of ultrasound technology over the last 20 years, it is now used as the first imaging modality to examine salivary gland pathologies. It allows a quick, dynamic, and non-invasive examination of the salivary glands and the soft tissue of the neck. In order to accurately diagnose and treat patients, a very good knowledge of these diseases and their appearance on sonography is required.

Radiomic nomogram for discriminating parotid pleomorphic adenoma from parotid adenolymphoma based on grayscale ultrasonography

Objectives

To differentiate parotid pleomorphic adenoma (PA) from adenolymphoma (AL) using radiomics of grayscale ultrasonography in combination with clinical features.

Methods

This retrospective study aimed to analyze the clinical and radiographic characteristics of 162 cases from December 2019 to March 2023. The study population consisted of a training cohort of 113 patients and a validation cohort of 49 patients. Grayscale ultrasonography was processed using ITP-Snap software and Python to delineate regions of interest (ROIs) and extract radiomic features. Univariate analysis, Spearman's correlation, greedy recursive elimination strategy, and least absolute shrinkage and selection operator (LASSO) correlation were employed to select relevant radiographic features. Subsequently, eight machine learning methods (LR, SVM, KNN, RandomForest, ExtraTrees, XGBoost, LightGBM, and MLP) were employed to build a quantitative radiomic model using the selected features. A radiomic nomogram was developed through the utilization of multivariate logistic regression analysis, integrating both clinical and radiomic data. The accuracy of the nomogram was assessed using receiver operating characteristic (ROC) curve analysis, calibration, decision curve analysis (DCA), and the Hosmer-Lemeshow test.

Results

To differentiate PA from AL, the radiomic model using SVM showed optimal discriminatory ability (accuracy = 0.929 and 0.857, sensitivity = 0.946 and 0.800, specificity = 0.921 and 0.897, positive predictive value = 0.854 and 0.842, and negative predictive value = 0.972 and 0.867 in the training and validation cohorts, respectively). A nomogram incorporating rad-Signature and clinical features achieved an area under the ROC curve (AUC) of 0.983 (95% confidence interval [CI]: 0.965-1) and 0.910 (95% CI: 0.830-0.990) in the training and validation cohorts, respectively. Decision curve analysis showed that the nomogram and radiomic model outperformed the clinical-factor model in terms of clinical usefulness.

Conclusion

A nomogram based on grayscale ultrasonic radiomics and clinical features served as a non-invasive tool capable of differentiating PA and AL.

Diagnostic value of shear wave elastography quantification combined with conventional ultrasound in salivary gland tumors

Background

The histopathological classification of salivary gland tumors is extremely complex. The imaging manifestations of some tumors are nonspecific. It is particularly important to improve the value of ultrasound in the diagnosis of salivary gland tumors. This study aimed to analyze the diagnostic value of different parameters of shear wave elastography (SWE) in the quantitative diagnosis of salivary gland tumors, and to evaluate the value of SWE combined with conventional ultrasound.

Methods

The study was conducted retrospectively. Patients who underwent salivary gland tumor resection from April 2021 to November 2022 in the Ninth People's Hospital, Shanghai Jiaotong University School of Medicine were randomly recruited to the study. A total of 305 masses were divided into an elastography group (150 cases) and a control group (155 cases). The control group underwent conventional ultrasonography, whereas the elastography group underwent conventional ultrasonography and elastography. The Young's modulus E of the mass was quantitatively measured in the elastography group, including maximum cross-sectional area (S), maximum Young's modulus (Emax), mean Young's modulus (Emean), and Young's modulus standard deviation (SD). Pathologic diagnosis was used as the reference standard to determine the cut-off of shear wave elastography of salivary gland tumors, and the diagnostic performance of the 2 groups was compared.

Results

In the elastography group, the diagnostic value of Emax·S (the product of the maximum Young's modulus of the mass and the maximum cross-sectional area of the mass) in the differential diagnosis of malignant tumors (MT) and non-malignant tumors (NMT) was the highest, with a sensitivity and specificity of 72.0% and 80.0%, respectively. The diagnostic value of Emax/D (the quotient of the maximum Young's modulus of the mass and the maximum diameter of the mass) in the differential diagnosis of pleomorphic adenoma (PA) and adenolymphoma (AL) was the highest, with a sensitivity and specificity of 62.3% and 82.4%, respectively. The receiver operating characteristic (ROC) curves for the diagnosis of salivary gland tumors were compared between the elastography group and the control group. The area under the curve (AUC) of the elastography group was 0.915, the sensitivity, specificity, and Youden index were 84.0%, 88.0%, and 0.720, respectively. The AUC of the control group was 0.906, the sensitivity, specificity, and Youden index were 76.0%, 90.0%, and 0.660, respectively, which is the main finding of the study.

Conclusions

SWE can be used as a complementary method for the diagnosis of salivary gland tumors, which has certain value in improving the diagnostic performance. As a result, the sensitivity is improved but the specificity is worsened by addition of SWE to B-mode ultrasound and color Doppler flow imaging (CDFI).

Impact of Screening for Salivary Gland by Ultrasonography

BACKGROUND

Ultrasonography is superior to other imaging modalities for detecting salivary gland diseases. However, there have been no reports of the results of salivary gland screening with ultrasonography. In this study, the salivary glands were also observed during thyroid ultrasonography to determine the degree of salivary gland abnormalities detected by ultrasonography.

METHODS

This study was conducted retrospectively using medical records. It assessed the association between the following abnormal findings detected during thyroid ultrasonography and their final diagnoses: atrophy/swelling, unclear demarcation from surrounding tissues, decreased salivary gland parenchyma echo level, heterogeneity of parenchyma, hypervascularity of salivary gland parenchyma, dilatation of the ducts, and a mass within the gland.

RESULTS

Of the 908 patients who underwent thyroid ultrasonography, salivary gland abnormalities were detected in 36 (4.0%) patients. Of the 36 patients with abnormal ultrasonographic findings, 22 underwent further examination. Of the 22 patients, 16 received definitive diagnoses of salivary gland diseases.

Salivary gland disorders were considered to be absent in patients with only heterogeneity of the salivary glands observed on ultrasonography. Salivary gland disorders in all patients with further abnormal ultrasonographic findings such as atrophy/swelling, unclear boundary, or hypervascularity in addition to internal heterogeneity were confirmed by further blood examinations and imaging studies. We were able to detect autoimmune sialadenitis such as Sjögren's syndrome and IgG4-related sialadenitis by ultrasonography in patients without obvious symptoms.

CONCLUSION

Salivary gland screening during thyroid ultrasonography revealed abnormal findings including Sjögren's syndrome and IgG4-related sialadenitis in about 4% of the patients. Thus, ultrasonography may also be useful for early detection of autoimmune diseases of salivary glands.

The effectiveness of high-resolution ultrasound in the assessment of the carotid intima-media thickness for postirradiated neck

OBJECTIVE

The carotid intimal-medial thickness (CIMT) is a strong predictor of future cardiovascular events. We assessed the mean CIMT and evaluated associated factors in head and neck cancer (HNC) patients.

MATERIALS AND METHODS

Between January 2016 and March 2018, 70 volunteers underwent automatic ultrasound measurement of the common carotid artery CIMT. A mean CIMT ≥ 1.0 mm was regarded as an elevated risk for cardiovascular disease (CVD). We aimed to investigate the risk factors for an increased mean CIMT.

RESULTS

We recruited 20 HNC survivors and 50 noncancer control individuals. Multiple linear regression analysis showed that old age (β = 0.006, 95% confidence interval, CI 0.004-0.008), increased weight (β = 0.003, 95% CI 0.001-0.005), hypertension (β = 0.10, 95% CI 0.03-0.17), and prior irradiation (β = 0.13, 95% CI 0.08-0.19) were positively correlated with the mean CIMT. From logistic regression analysis, it was shown that patients who underwent radiotherapy (OR 13.5, 95% CI 1.48-122.8) and who had higher bodyweight (OR 1.09, 95% CI 1.01-1.18) had a significantly higher risk of developing CVD.

CONCLUSION

Measurement of the mean CIMT using ultrasound could be useful for assessing CVD risk in HNC survivors after neck irradiation.