Role of Ultrasonography And Elastography In Evaluation Of Solid Thyroid Nodules.

Abstract

OBJECTIVES: To characterize the thyroid nodules on shear wave elastography by virtual touch tissue quantification (VTQ) technique using acoustic radiation force impulse (ARFI). To correlate the observations of elastography with cytological and/or histopathological diagnosis and establish a reference value of elastographic parameters for benignancy and malignancy. To compare the accuracy of shear wave elastography in differentiating benign and malignant thyroid nodules with that of grey scale ultrasound and Doppler findings using pathological diagnosis as a reference standard. MATERIALS AND METHODS: This is a prospective study that has been carried out on 60 patients who were detected to have a thyroid nodule on ultrasound in Sri B M Patil medical college, Vijayapura. The ultrasound characteristic of each nodules were determined and classified using TIRADS and then these nodules were evaluated using shear wave elastography. The findings of ultrasound and elastography were correlated with histopathological diagnosis. The sensitivity, specificity, positive predictive value and negative predictive value of ultrasound features and shear wave elastography and then were compared with each other. RESULTS: Out of the 60 patients evaluated for the thyroid nodules. The nodules were most commonly seen in the females with gender distribution of (8:1), among which there was no significant correlation of the gender predilection to the malignancy. There is DocuSign Envelope ID: 3B8BA3968D6C58C0--86E2D68E--442A4069--89C598B3-8DDA89115C5D501CFC6B0068 statistical significance of the shear wave velocity in determining the malignant nodule with p<0.05. There is also statistical significance among some of the ultrasound features including hypoechogenecity, taller than wide, microcalcification, lobulated or poorly defined margins and lymphadenopathy in determining the malignant thyroid nodules (p<0.05). The shear wave velocity has a higher sensitivity and specificity in determining the malignant nodules as compared to the USG using TIRADS; with SWV showing a sensitivity of 93.3 % and specificity of 80 %. CONCLUSION: The shear wave elastography technique using virtual touch tissue quantification technique (VTQ) considering shear wave velocity and black and white color coding of the thyroid nodule, is more sensitive and specific modality in differentiating benign and malignant thyroid nodules than the US TIRADS. Considering 2.83 cm/s as a cutoff value of SWV there is high sensitivity of 93 % and specificity of 80 % in differentiating the benign and malignant nodules.