Aims and objectives
Thyroid nodules are extremely common with prevalence over 50% in autopsy specimens,
while only a small proportion are malignant (5-15%) [1].
Conventional ultrasound (US) is used widely as a first line imaging technique for thyroid evaluation [2,
3].
US is sensitive for detecting thyroid nodules and has utility for characterization as several conventional sonographic features are predictive of malignancy or benignity.
However,
its overall accuracy for malignancy is suboptimal as no single criterion is highly accurate,
while combining criteria increases the specificity at the cost...
Methods and materials
From January to December 2013,
thyroid SWE was performed in 57 subjects using a 4-15 MHz linear transducer on commercially available clinical shear wave ultrasound system (Aixplorer,
SuperSonic Imagine,
Aix en Provence,
France).
SWE was performed on different thyroid tissue types as follows: 38 normal thyroid glands (Norm),
27 benign hyperplastic nodules (MNG) and 5 papillary carcinomas (PapCa).
Subjects were either normal volunteers or patients referred for thyroid US assessment,
and the final diagnosis of thyroid nodules was based on sonographic,
cytological ± histological results...
Results
The mean SWE kPa values of each thyroid tissue type at different levels of compression are shown in Table 1 (Fig.
3).
All tissue types had higher SWE stiffness at high compared to lower compression levels (P values <0.05).
SWE values were higher for papillary carcinoma than benign hyperplastic nodules,
and both tissues types were higher than normal parenchyma (P values <0.05).
Of importance,
these differences were statistically significant at all compression levels except for hyperplastic nodule vs.
papillary carcinoma at minimal compression level (Table...
Conclusion
Absolute SWE stiffness measurements (kPa) of normal thyroid tissue,
hyperplastic nodules and papillary carcinoma vary depending on the resting pressure applied by the transducer.
The differences in SWE stiffness results between papillary carcinoma and hyperplastic nodules are greater at higher levels of compression than at lower compression levels.In our study,
there was no significant difference in mean SWE stiffness values between papillary carcinoma and hyperplastic nodules at minimal compression level,
which refers to minimal contact of the transducer with the skin (evidenced by a thick...
References
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Yuen,
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& Ahuja,
a T.
(2011).
Cystic change in thyroid nodules: a confounding factor for real-time qualitative thyroid ultrasound elastography.
Clinical radiology,
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[2] Sebag,
F.,
Vaillant-Lombard,
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Berbis,
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Griset,
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Henry,
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Shear Wave Elastography: A New Ultrasound Imaging Mode for the Differential Diagnosis of Benign and Malignant Thyroid Nodules.
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