Comparison of strain elastography, point shear wave elastography using acoustic radiation force impulse imaging and 2D-shear wave elastography for the differentiation of thyroid nodules

Abstract

PurposeThe aim of the study was to compare three different elastography methods, namely Strain Elastography (SE), Point Shear-Wave Elastography (pSWE) using Acoustic Radiation Force Impulse (ARFI)-Imaging and 2D-Shear Wave Elastography (2D-SWE), in the same study population for the differentiation of thyroid nodules.Materials and methodsAll patients received a conventional ultrasound scan, SE and 2D-SWE, and all patients except for two received ARFI-Imaging. Cytology/histology of thyroid nodules was used as a reference method. SE measures the relative stiffness within the region of interest (ROI) using the surrounding tissue as reference tissue. ARFI mechanically excites the tissue at the ROI using acoustic pulses to generate localized tissue displacements. 2D-SWE measures tissue elasticity using the velocity of many shear waves as they propagate through the tissue.Results84 nodules (73 benign and 11 malignant) in 62 patients were analyzed. Sensitivity, specificity and NPV of SE were 73%, 70% and 94%, respectively. Sensitivity, specificity and NPV of ARFI and 2D-SWE were 90%, 79%, 98% and 73%, 67%, 94% respectively, using a cut-off value of 1.98m/s for ARFI and 2.65m/s (21.07kPa) for 2D-SWE. The AUROC (Area under the Receiver Operating Characteristic) of SE, ARFI and 2D-SWE for the diagnosis of malignant thyroid nodules were 52%, 86% and 71%, respectively. A significant difference in AUROC was found between SE and ARFI (p = 0.008), while no significant difference was found between ARFI and SWE (86% vs. 71%, p = 0.31), or SWE and SE (71% vs. 52%, p = 0.26).ConclusionpSWE using ARFI and 2D-SWE showed comparable results for the differentiation of thyroid nodules. ARFI was superior to elastography using SE.

Accuracy of real-time shear wave elastography in staging hepatic fibrosis: a meta-analysis

“…Our analysis showed that the pooled sensitivity (88%) and specificity (91%) of SWE in detecting and staging early cirrhosis (F1) are similar to those of TE [37,48], acoustic radiation force impulse (ARFI) [49] and RTE [50,51], those sensitivity and specificity are 83 and 89%, 87 and 87%, 74 and 84%, respectively. ARFI is very similar to SWE, which targets an anatomic region to be interrogated for elastic properties with a Region-of-Interest (ROI) cursor [52]. However, for significant fibrosis (F ≥ 2), the overall sensitivity and specificity of SWE are greater than these of TE and RTE, and similar to these of ARF.…”

Elastography for the diagnosis of high-suspicion thyroid nodules based on the 2015 American Thyroid Association guidelines: a multicenter study

“…Though the SR is a semiquantitative method, it is defined as the ratio obtained by dividing the mean strain within the lesion by the mean strain of the surrounding normal tissue; thus, thyroid echogenicity surrounding thyroid nodules will inevitably affect the SR. As a result, it might be inferred that no additional information is provided by the SR, which is more time consuming than the ES, in the discrimination of malignant from benign thyroid nodules. Although shear wave elastography (SWE) has drawn more attention in recent years and has been reported to be more accurate than USE in some studies [30][31][32], Tian et al's and Hu et al's meta-analysis showed that USE had a better diagnostic performance than SWE, with comparable specificity between methods [33,34]. Even more recently, a prospective study comprising 243 nodules revealed that USE yielded the highest performance compared with the TI-RADS score and SWE [35].…”

Schilddrüsen-Elastografie

“…Dabei wird die Ausbreitungsgeschwindigkeit je nach Verfahren entweder in m/s angegeben oder die Steifheit durch eine Formel aus Gewebedichte und Ausbreitungsgeschwindigkeit berechnet und in kPa angegeben. Der direkte Vergleich unterschiedlicher Elastographiemethoden zeigt für alle Verfahren eine sehr gute Anwendbarkeit, möglicherweise mit geringen, im Alltag mutmaßlich nicht relevanten Vorteilen für die Shear-Wave Verfahren [36].…”