Diagnostic Performance of Point Shear-Wave Elastography in Peripheral Pulmonary Consolidations of Various Etiologies: A Retrospective Analysis of n=87 Patients

Background: Ultrasound elastography has emerged as a non-invasive tool to “palpate” the previously unpalpable deeply buried organs and has established itself as a reliable, radiation-free and a cost-effective diagnostic equipment for quantifying the degree of stiffness of various normal and pathological tissues in the body. Given the aerated nature of pulmonary parenchyma; studies on lung elastography are scarce. Very few studies examined the use of ARFI in peripheral pulmonary consolidations (PPCs) and almost all of them excluded consolidations accompanied by pleural effusion (PE). The purpose of this study was to evaluate the diagnostic performance of ultrasound (US) point shear wave elastography (pSWE) using Acoustic Radiation Force Impulse (ARFI) technology in different benign and malignant PPCs. Methods: 107 consecutive patients with PPCs who underwent sonographic examinations between April to December 2020 at the university hospital of Marburg, Germany were recruited in the study. A verbal consent was obtained from each patient to perform an ARFI study of the PPC. 20 patients (n=20) were excluded due to the following reasons: 10 patients (n=10) due to measurement’s failure, 5 patients (n=5) due to incompliance (breath holding) with invalid measurements, 5 PPCs (n=5) due to uncertain diagnosis. Finally, 87 patients (n=87) were included in the final analysis. The ARFI studies were retrospectively analyzed and correlated to the final diagnosis. All patients received a conventional lung US examination in addition to an ARFI study (11 valid measurements in meters per second (m/s) were obtained for each PPC). Atelectatic consolidations accompanied by pleural effusions (PE) were also included. The diagnosis was confirmed by means of cyto-histological examination (performed in 73/87 (83.9%) of the patients) or by means of computer tomography (CT) and or chest-X-ray in correlation to the clinical picture (a CT scan was available in 84/87 (96.6%) of the cases). A receiver operating characteristic (ROC) analysis was implemented to examine the mean ARFI velocities (MAV) for potential cut-off values between benign and malignant PPCs. The study was approved by the local ethics committee of the Philipps-university in Marburg. Results: The 87 patients (49 males and 38 females) had a mean age of 65±14 years (range 28-88 years). The mean body mass index (BMI) was 24.1±3.5 Kg/m2. History of smoking and chronic pulmonary disease (CPD) was present in 61% (53/87) and 36% (31/56), respectively. 55% (48/87) of the PPCs were accompanied by PE. There was 58 benign PPCs (bPPCs) and 29 malignant PPCs (mPPCs). Large consolidation’s size was suggestive of malignancy (p=0.01), the mean size of mPPCs was 6.26 ±3.12 cm and of bPPCs 4.02 ±1.98 cm. A cutoff size of 4.75 cm has a sensitivity and specificity of 65.5% and 82.5%, respectively in diagnosing mPPCs (AUC=0.729, 95% CI= 0.577-0.881). Consolidations accompanied by PE had lower MAV values and were more likely to be benign (P 0.05). bPPCs demonstrated significantly lower MAV values as mPPCs (1.82±0.97 vs. 3.05±0.73 m/s) (p<0.001). Selecting 2.21 m/s as a cut-off value yielded a sensitivity and specificity of 89.7% and 75.9%, respectively in diagnosing mPPCs (AUC=0.852, 95% CI =0.773-0.931). No significant differences were found between atelectases due to benign underlying causes (AT-b, n=21) and those due to malignant underlying causes (AT-m, n=17) (p=0.33) nor between pneumonias (n=9) and all atelectases (n=38) (P=0.66). Lung infarctions and certain other chronic inflammatory/granulomatous benign consolidations (n=11) showed high MAV values comparable to those of mPPCs (p=0.42). One interesting finding was the higher stiffness of primary lung tumors (n=19, MAV= 3.33 ±0.71 m/s) vs. metastases (n=10, MAV=2.52 ±0.39 m/s) (p= 0.002). Setting 2.82 m/s as a cut-off value would have a sensitivity and specificity of 79.0% and 90.0 %, respectively in differentiating primary lung tumors from metastases (AUC=0. 847, 95% CI= 0.701-0.993). Conclusion: ARFI elastography could be a good non-invasive tool in the diagnostic armamentarium of peripheral pulmonary consolidations helping in the differentiation between benign and malignant consolidations as well as between malignant consolidations of pulmonary and non-pulmonary origins (metastases). However, some degree of overlap between different disease entities does exist and the diagnosis should be made in correlation with the clinical context, larger prospective studies are needed to validate these results

ARFI elastography of the omentum: feasibility and diagnostic performance in differentiating benign from malignant omental masses

Objective: To evaluate the feasibility and diagnostic performance of acoustic radiation force impulse (ARFI) elastography in different omental masses (OM). Design: This was a retrospective analysis of 106 patients with OM defined as omental thickness ≥1 cm, who underwent abdominal B-mode ultrasound (US) and standardised ARFI examinations of the OM between September 2018 and June 2021 at our university hospital. A cytohistological confirmation was available in 91/106 (85.8%) of all OM, including all 65/65 (100%) malignant OM (mOM) and 26/41 (63.4%) of benign OM (bOM). In 15/41 (36.6%) of bOM; cross-sectional imaging and or US follow-up with a mean duration of 19.8±3.1 months was performed. To examine the mean ARFI velocities (MAV) for potential cut-off values between bOM and mOM a receiver operating characteristic analysis was implemented. Results: The MAV in the mOM group (2.71±1.04 m/s) was significantly higher than that of bOM group (1.27±0.87 m/s) (p[0.001). Using 1.97 m/s as a cut-off yielded a sensitivity and specificity of 76.9% and 85.4%, respectively, in diagnosing mOM (area under the curve=0.851, 95% CI=0.774 to 0.928). Conclusion: ARFI elastography is feasible in the omentum and may represent a good non-invasive additional tool in differentiating bOM from mOM

Diagnostic Performance of Point Shear Wave Elastography (pSWE) Using Acoustic Radiation Force Impulse (ARFI) Technology in Mesenteric Masses: A Feasibility Study

Purpose: To evaluate the diagnostic performance of ultrasound point shear wave elastography (pSWE) using acoustic radiation force impulse (ARFI) technology in different benign and malignant mesenteric masses (MMs). Methods: A total of 69 patients with MMs diagnosed from September 2018 to November 2021 were included retrospectively in the study. The inclusion criteria were (1) an MM over 1 cm; (2) valid ARFI measurements; and (3) confirmation of the diagnosis of an MM by histological examination and/or clinical and radiological follow-up. To examine the mean ARFI velocities (MAVs) for potential cut-off values between benign and malignant MMs, a receiver operating characteristics analysis was implemented. Results: In total, 37/69 of the MMs were benign (53.6%) and 32/69 malignant (46.4%). Benign MMs demonstrated significantly lower MAVs than mMMs (1.59 &plusmn; 0.93 vs. 2.76 &plusmn; 1.01 m/s; p &lt; 0.001). Selecting 2.05 m/s as a cut-off value yielded a sensitivity and specificity of 75.0% and 70.3%, respectively, in diagnosing malignant MMs (area under the curve = 0.802, 95% confidence interval 0.699&ndash;0.904). Conclusion: ARFI elastography may represent an additional non-invasive tool for differentiating benign from malignant MMs. However, to validate the results of this study, further prospective randomized studies are required

ARFI elastography of the omentum: feasibility and diagnostic performance in differentiating benign from malignant omental masses

Objective To evaluate the feasibility and diagnostic performance of acoustic radiation force impulse (ARFI) elastography in different omental masses (OM).Design This was a retrospective analysis of 106 patients with OM defined as omental thickness ≥1 cm, who underwent abdominal B-mode ultrasound (US) and standardised ARFI examinations of the OM between September 2018 and June 2021 at our university hospital. A cytohistological confirmation was available in 91/106 (85.8%) of all OM, including all 65/65 (100%) malignant OM (mOM) and 26/41 (63.4%) of benign OM (bOM). In 15/41 (36.6%) of bOM; cross-sectional imaging and or US follow-up with a mean duration of 19.8±3.1 months was performed. To examine the mean ARFI velocities (MAV) for potential cut-off values between bOM and mOM a receiver operating characteristic analysis was implemented.Results The MAV in the mOM group (2.71±1.04 m/s) was significantly higher than that of bOM group (1.27±0.87 m/s) (p&lt;0.001). Using 1.97 m/s as a cut-off yielded a sensitivity and specificity of 76.9% and 85.4%, respectively, in diagnosing mOM (area under the curve=0.851, 95% CI=0.774 to 0.928).Conclusion ARFI elastography is feasible in the omentum and may represent a good non-invasive additional tool in differentiating bOM from mOM

Ultrasound Elastography for Characterization of Focal Liver Lesions.

Focal liver lesions (FLL) are typically detected by conventional ultrasound or other imaging modalities. After the detection of FLL, further characterization is essential, and this can be done by contrast-enhanced imaging techniques, e.g., contrast-enhanced ultrasound (CEUS) and magnetic resonance imaging (MRI) or by means of biopsy with histological evaluation. Elastographic techniques are nowadays integrated into high-end ultrasound systems and their value for the detection of severe liver fibrosis and cirrhosis has been shown in studies and meta-analyses. The use of an ultrasound elastographic technique for the differentiation of malignant and benign liver tumors is less well-established. This review summarizes the current data on utility and performance of ultrasound elastography for the characterization of FLL

The Value of Contrast-Enhanced Ultrasound (CEUS) in the Detection of Perfusion Disturbances in Abdominal Wall Hernias Compared with Surgical and Histological Assessment

Purpose: This study aimed to evaluate the value of contrast-enhanced ultrasound (CEUS) in the evaluation of perfusion disturbance in irreducible abdominal wall hernias (AWHs). Methods: From 2006 to 2018, 50 patients with an irreducible AWH were examined using B-mode ultrasound (B-US) and CEUS. The ultrasound findings were correlated with subsequent surgical and histological results. The presence of non-enhanced areas (NEAs) in hernia contents on CEUS and the presence of non-perfused areas (NPAs) on surgical and histological evaluation were analyzed retrospectively. Results: On CEUS, 13/50 hernia contents (26.0%) revealed NEAs during complete CEUS examination and 37/50 (74.0%) revealed no NEAs during CEUS examination. On surgical and histological evaluation, NPAs in hernia contents were identified in 11/13 cases (93.3%) with NEAs on CEUS. CEUS was found to have a sensitivity of 100.0%, a specificity of 94.9%, a positive predictive value of 84.6%, and a negative predictive value of 100.0% for the identification of perfusion disturbance in AWHs. Conclusions: The findings of this study demonstrate that using CEUS as an imaging method may be helpful for evaluating the perfusion of hernia contents in incarcerated AWHs. On CEUS, the presence of NEAs may suggest perfusion disturbance in hernia contents