Online Journal
IF値: 0.966(2018年)→0.898(2019年)


Journal of Medical Ultrasonics

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2016 - Vol.43

Vol.43 No.Supplement

特別プログラム 甲状腺
シンポジウム 甲状腺 Joint(JSUM・AFSUMB・JABTS Joint Session)(English) Artifacts and Pitfalls in Elastography of the Breast and Thyroid Ultrasound


甲状腺におけるshear wave測定へのアーチファクトの検証

Verification of artifacts in the measurement of shear wave velocity in the thyroid

福原 隆宏, 松田 枝里子, 北野 博也, 竹内 裕美



Department of Otolaryngology-Head and Neck Surgery, Tottori University Faculty of Medicine

キーワード :

Introduction: Shear waves are transverse waves that are very slow in comparison with acoustic waves, and are therefore predicted to be easily affected by factors in the physiological environment. However, the degree to which such physical artifacts affect shear waves is unknown.
The aim of this study was to elucidate the physiological artifacts in the measurement of shear wave velocity(SWV)by comparing the SWV in vivo with that assessed in resected specimens.
Subjects and Methods: The materials were unselected thyroid and lymph node specimens resected during thyroid surgery. We performed shear wave elastography using an ACUSON S2000 ultrasound system(Siemens Medical Systems, Germany).
We performed 5 measurements at the same location in each subject and used the average values for analysis. Immediately after surgery, fresh unfixed thyroid and metastatic lymph node specimens were suspended in gel phantoms and SWV was measured 5 times. The variability of the 5 measurements was compared by lesion type as well as between the in vivo and ex vivo assessments.
A total of 101 specimens were evaluated. The median SWV values of each lesion measured in vivo and ex vivo, and the measurable/unmeasurable ratios are shown Table 1. For the lesions overall, the median SWV values in vivo were higher than those ex vivo.
The variability of the 5 measurements obtained ex vivo was smaller than that assessed in vivo(Figure 1).
Measurements of SWV were judged to be negligibly affected by physical artifacts such as carotid artery or pulsation respiratory movements. The pathological structure, mainly involving fibrotic tissue, affected the ability to obtain SWV measurements as well as their values. Furthermore, physical artifacts, particularly blood flow, may partially affect the measurement of SWV.