Evaluation of Strain Elastography for Differentiation of Thyroid Nodules: Results of a Prospective DEGUM Multicenter Study

Abstract

▼Purpose: Many patients with thyroid nodules are presently referred to surgery for not only therapeutic but also diagnostic purposes. The aim of noninvasive diagnostic methods is to optimize the selection of patients for surgery. Strain elastography (SE) enables the ultrasound-based determination of tissue elasticity. The aim of the present study was to evaluate the value of SE for the differentiation of thyroid nodules in a prospective multicenter study. Materials and Methods: The study was registered at clinicaltrials.gov and was approved by the local ethics committees of all participating centers. All patients received an ultrasound (US) of the thyroid gland including color Doppler US. In addition, all nodules were evaluated by SE (Hitachi Medical Systems) using qualitative image interpretation of color distribution (SE-ES), strain value and strain ratio. Results: Overall, 602 patients with 657 thyroid nodules (567 benign, 90 malignant) from 7 centers were included in the final analysis. The sensitivity, specificity, NPV, PPV, +LR were 21 %, 73 %, 86 %, 11 %, 0.8, respectively, for color Doppler US; 69 %, 75 %, 94 %, 30 %, 2.9, respectively, for SE-ES; 56 %, 81 %, 92 %, 32 %, 2.9, respectively, for SEstrain value; and 58 %, 78 %, 92 %, 30 %, 2.6, respectively, for SE-strain ratio. The diagnostic accuracy was 71 % for both strain value and strain ratio of nodules. Conclusion: SE as an additional ultrasound tool improves the value of ultrasound for the workup of thyroid nodules. It might reduce diagnostic surgery of thyroid nodules in the future. Zusammenfassung ▼Ziel: Viele Patienten mit Schilddrüsenknoten werden nicht nur therapeutisch, sondern auch zu diagnostischem Zweck operiert. Ziel von nicht-invasiven diagnostischen Verfahren ist es daher die Selektion von Patienten zur Operation zu optimieren. Strain Elastografie (SE) ermöglicht die Ultraschall-basierte Messung der Gewebeelastizität. Das Ziel der vorliegenden Studie war es den Stellenwert der SE in einer prospektiven Multizenter-Studie für die Differenzierung von Schilddrüsenknoten zu evaluieren. Material und Methoden: Die Studie wurde bei clinicaltrials.gov registriert und von den lokalen Ethikkommissionen der teilnehmenden Zentren genehmigt. Alle Patienten erhielten einen Ultraschall (US) der Schilddrüse inklusive Farbduplex-US. Zusätzlich wurden alle Knoten mittels SE (Hitachi Medical System) untersucht und eine Beurteilung der qualitativen Farbverteilung (SE-ES) und eine semiquantitative Messung der Elastizität mittels strain value und strain ratio durchgeführt. Ergebnisse: Insgesamt wurden 602 Patienten mit 657 Schilddrüsenknoten (567 benigne, 90 maligne) an 7 deutschen Zentren ausgewertet. Sensitivität, Spezifität, NPV, PPV, und +LR betrugen entsprechend 21 %, 73 %, 86 %, 11 %, 0,8 für den Duplex-US; 69 %, 75 %, 94 %, 30 %, 2,9 für SE-ES; 56 %, 81 %, 92 %, 32 %, 2,9 für SE-strain value; 58 %, 78 %, 92 %, 30 %, 2,6 für SE-strain ratio. Die diagnostische Genauigkeit betrug 71 % sowohl für SEstrain value, als auch SE-strain ratio. Schlussfo...

Intra- and inter-observer variation and accuracy using different shear wave elastography methods to assess circumscribed objects – a phantom study.

“…US elastography is increasingly used for the diagnosis of stiffness in numerous circumscribed tissues [1,[4][5][6][7][8][9][10][11][12][13][14][15][16][17]. To date, there has been a lack of phantom studies which have systematically assessed the current US shear wave elastography techniques (pSWE with fixed ROI vs. 2D-SWE with variable ROI) in an effort to evaluate their suitability/test performance for this condition.…”

“…In contrast, US elastography yields objective (semi-)quantitative findings on tissue stiffness and also penetrates into regions of the human body previously inaccessible to physicians' hands -except intraoperatively. Other organs or tissues have thus been examined by means of US elastography besides the liver, breasts, and thyroid, for which examination techniques have already been established worldwide [1][2][3].…”

“…Elastic properties of circumscribed tissues and organs that are not accessible to physicians' hands (a), or which require measurements in a small, localized area (b) are of considerable clinical interest [1,[4][5][6][7][8][9][10][11][12][13][14][15][16][17]. Examples are: tendons/ligaments a/b , lymph nodes a/b , myometria a , prostates b , cervix uteri b , testicles b , anal sphincter muscles b , arterial plaques a/b , muscles a , intervertebral discs a/b , thyroid nodules a/b , and brain tumors a/b .…”

Porównanie skuteczności elastografii w diagnostyce zmian pęcherzykowych tarczycy i ognisk z jednoznacznym wynikiem BAC

“…[52] found that in nodules with unequivocal cytology the model based on the presence of suspected SR or suspected NoUMRFs improved SEN, but worsened SPC in comparison with the analysis of the NoUMRFs alone. Friedrich-Rust et al [53] analysed non-preselected nodules and found that optimal SEN and SPC (85% and 68%) can be achieved in the model expecting the presence of at least four of the following features: ES ≥ 3, SR > 2.66, microcalcifications, macrocalcifications, no halo, irregular margins, and pathological pattern of the blood flow. According to our knowledge, none of the published reports assessed the combination of SR and the NoURMFs in FL nodules, which was examined in our study.…”

“…As was mentioned before, the elastographic evaluation is performed in various, non-uniform ways. Thus, in our study, following published data [16,21,27,31,36,44,45,53], and on the basis of our own experience, we specified the exclusion criteria and described precisely the applied measurement technique. Because the study included the comparison of the efficacy of ES and SR in both sections, it was limited to the nodules with a suitable reference area available in both sections at similar depth.…”