Accuracy Of Ultrasound Elastography Research Articles

The role of elastography in the assessment of thyroid nodules in acromegaly.

Nodular thyroid disease is a frequent finding seen in patients with acromegaly. Ultrasound-elastography (US-E) appears to be a helpful tool for the diagnosis of thyroid cancer. The aims of this study were to evaluate thyroid nodules in acromegaly and to assess the diagnostic accuracy of US-E in detecting thyroid cancer in this population. US-E was applied to 166 nodules detected in 102 acromegalic patients and to 105 nodules found in 95 nonacromegalic subjects. The lesions were classified according to the elasticity scores (ES) as soft (ES 1-2) or hard (ES 3-4). : Mean age was 55.1 ± 12.47 years [59 (58%) women]. The prevalence of hard nodules (ES 3 and 4) was significantly higher in the group of acromegalic patients than in control subjects (48% to 20%, p < 0.001). Mean ES was higher in patients with acromegaly (2.45 to 2.22, p: 0.001), however, the mean strain index (SI) was similar between groups (1.53 to 1.65, p: 0.204). Thyroid nodules in acromegaly patients have a higher elasto score and the prevalence of hard nodules is higher in active disease. However, increased stiffness of nodules by US-E in patients with acromegaly does not seem to estimate the malignancy of the nodules.

Accuracy of Ultrasound Elastography and Fibrosis-4 Index (FIB-4) in Ruling Out Cirrhosis in Obese Non-Alcoholic Fatty Liver Disease (NAFLD) Patients.

Introduction: Non-alcoholic fatty liver disease (NAFLD) is the most common cause of advanced liver disease in the USA. Liver biopsy, the gold standard diagnostic test for evaluating liver fibrosis, is associated with significant risk and expense. The accuracy of ultrasound elastography and Fibrosis-4 index (FIB-4) in the obese NAFLD population is unknown. We aimed to compare the accuracy of ultrasound elastography and FIB-4 to liver biopsy in ruling out cirrhosis in NAFLD patients at a tertiary, transplant referral center in the US.Methods: We retrospectively evaluated 93 patients with a mean age of 53 years (SD: 13 years) who underwent liver ultrasound elastography and liver biopsy, and additionally calculated their FIB-4 at the time of biopsy. We compared the liver stiffness measurement (LSM) obtained from ultrasound elastography and FIB-4 with the pathology results for ruling out cirrhosis.Results: 85% of the patients were white, 53% were female, average BMI was 34.7 (SD: 6.7), 52% had diabetes, and 53% had hypertension. For biopsy-proven cirrhosis (prevalence 15%), a cut-off value of 12.5 kilopascals (kPa) for F4 had a sensitivity of 92% and a specificity of 54%. Values below this threshold excluded cirrhosis with 98% certainty. Compared to FIB-4, ultrasound elastography showed higher accuracy in ruling out cirrhosis (92% vs. 80% sensitivity, 98% vs. 95% negative predictive value (NPV), respectively).Conclusion: To our knowledge, this is the first study in a tertiary transplant referral center in the USA to show that ultrasound elastography was superior to FIB-4 and can be used as a reliable screening test to rule out cirrhosis in obese NAFLD patients at a 12.5 kPa cut-off. Therefore, helping to avoid the risk and expense associated with liver biopsy.

Evaluation of the Property of Axillary Lymph Nodes and Analysis of Lymph Node Metastasis Factors in Breast Cancer by Ultrasound Elastography.

This research was aimed at investigating the role of ultrasound elastography (UE) in evaluating the properties of axillary lymph nodes in breast cancer and exploring the influencing factors of lymph node metastasis in breast cancer patients. Routine ultrasonography (US) and UE were performed for 160 breast cancer patients. 80 cases were in the group with lymph node metastasis, and the other 80 were in the nonlymph node metastasis group. The sensitivity, specificity, and accuracy of the two ultrasound examinations were compared, the receiver-operator characteristic (ROC) curves were drawn, and the influencing factors of lymph node metastasis were analyzed. The sensitivity, specificity, and accuracy of UE in diagnosing axillary lymph nodes of breast cancer were 97.22%, 95.45%, and 96.25%, respectively, which were markedly higher than those of routine US (P < 0.05). Cortical thickness, blood flow grade, blood flow type, and elasticity score had a greater impact on axillary lymph node metastasis of breast cancer. When cortical thickness ≥ 3 cm, blood flow was of 2-3 grades, blood flow was the peripheral/mixed type, and elasticity score was 3-4 points, these became risk factors for lymph node metastasis in breast cancer patients. UE was effective in diagnosing the property of lymph nodes and could evaluate lymph node metastasis in breast cancer patients. It had a good clinical value and was worthy of popularization and application.

P14.01: Diagnostic accuracy of ultrasound elastography in predicting preterm labour: a systematic review and meta‐analysis

P14.01: Diagnostic accuracy of ultrasound elastography in predicting preterm labour: a systematic review and meta‐analysis

A comparative study of high resolution ultrasound and ultrasound elastography in the defferential diagnosis of benign and malignant tumors in thyroid nodules

Objective To detect the efficiency of high resolution ultrasound in the differential diagnosis of benign and malignant thyroid nodules, to compare the vaule of high resolution ultrasound and ultrasound elastography in the differential diagnosis of benign and malignant tumors in thyroid nodules. Methods A total of 148 thyroid nodules from 123 patients were reviewed and analyzed by high resolution ultrasound and ultrasound elastography. With pathological findings as the golden diagnosis standard , using Logistic regression model, valuable indicators from the examination were screenrd.The sensitivity,specificity,accuracy and Kappa of high resolution ultrasound were compared with ultrasound elastography in the defferential diagnosis of benign and malignant tumors in thyroid nodules. Results Logistic regression model showed echostruction, shape and calcification were independent risk factors of the differential diagnosis of benign and malignant under high resolution ultrasound Examination of thyroid nodules.The best diagnosis criteria of high resolution ultrasound met any four of eight indicators ,with sensitivity,specificity,accuracy and Kappa of 70.7%,78.1%,73.3% and 0.454 respectively. The diagnosis criteria of ultrasound elastography was the elasticity score≥3, with sensitivity,specificity,accuracy and Kappa of 70.6%,90.0%,83.0% and 0.622 respectively. Conclusions Echostruction, shape and calcification were independent determinants of the differential diagnosis of benign and malignant under high resolution ultrasound Examination of thyroid nodules.The specificity and accuracy of ultrasound elastography are higher in the differential diagnosis of benign and malignant thyroid nodules,ultrasound elastography are more helpful to raising accuracy in defferential diagnosis of benign and malignant thyroid nodules combinated application of high resolution ultrasound Examination. Key words: High resolution ultrasound; Elastography; Thyroid nodules

Real time shear waves elastography monitoring of thermal ablation: in vivo evaluation in pig livers

BackgroundThermal ablation is a widely used minimally invasive treatment modality for different cancers. However, lack of a real-time imaging system for accurate evaluation of the procedure is one of the reasons of local recurrences. Shear waves elastography (SWE) is a new ultrasound (US) imaging modality to quantify tissue stiffness. The aim of the study was to assess the feasibility and accuracy of US elastography for quantitative monitoring of thermal ablation and to determine the elasticity threshold predictive of coagulation necrosis. MethodsA total of 29 in vivo thermal lesions were performed in pig livers with radiofrequency system. SWE and B-mode images were acquired simultaneously. Liver elasticity was quantified by using SWE data and expressed in kilopascal. After the procedure, pathologic analysis of treated tissues was compared with US images. The sensitivity and positive predictive value of the SWE maps of tissue elasticity were calculated and compared with the boundaries of the pale coagulation necrosis areas found at pathology. ResultsThe liver mean elasticity values before and after thermal therapy were 6.4 ± 0.3 and 38.1 ± 2.5 kPa, respectively (P < 0.0001). For a threshold of 20 kPa, sensitivity (i.e., the rate of pixels correctly detected as necrosed tissue) was 0.8, and the positive predictive value (i.e., the rate of pixels in the elastographic map >20 kPa that actually developed coagulation necrosis) was 0.83. ConclusionsTissue areas with coagulation necrosis are significantly stiffer than the surrounding tissue. SWE permits the real-time detection of coagulation necrosis produced by radiofrequency and could potentially be used to monitor US-guided thermal ablation.

Ultrasound Elastography of Breast Lesions in Chinese Women: A Multicenter Study in China

PurposeThrough analysis, the elastograms characteristics of breast lesions of Chinese women, a suitable diagnostic standard of quasistatic ultrasound elastography (UE) for Chinese women was proposed. MethodsFrom June 2010 to March 2012, 1036 consecutive female patients (mean age, 44 years old) with breast lesions were recruited into a multicenter retrospective study, which involved 8 centers across China. Each institutional ethic review board approved the study, and all the patients gave written informed consent. All breast lesions underwent ultrasound and UE examination. Two radiologists analyzed the elastograms and separated the elastograms into 10 types. A final diagnosis was made on the basis of histologic findings. The characteristics of the elastograms were analyzed. Receiver operating characteristic curves were plotted for evaluating the diagnostic performance. Sensitivity, specificity, and accuracy were calculated. Differences in sensitivity, specificity, and accuracy were tested by using the McNemar test. ResultsThere were 1150 lesions (593 benign, 557 malignant). There was a highly significant correlation between the elastogram color distribution and the percentage of malignant lesions, with a value of 0.92 (2P < .0001). Through analysis the different malignant percentages in different elastogram types, UE diagnostic standard was proposed, which was correlated with the blue percentage in the elastogram. The specificity, sensitivity, and accuracy of UE were 86.4%, 80.8%, and 83.5%, respectively. The specificity and accuracy of UE were higher than with ultrasound. The area under the curve was 0.86. ConclusionUE could give valuable assessment in the diagnosis of breast lesions. The proposed UE diagnostic standard was suitable for Chinese women.

Real Time Shear Waves Elastography Monitoring of Thermal Ablation: In Vivo Evaluation in Pig Livers

Abstract Background Thermal ablation is a widely used minimally invasive treatment modality for different cancers. However, lack of a real-time imaging system for accurate evaluation of the procedure is one of the reasons of local recurrences. Shear waves elastography (SWE) is a new ultrasound (US) imaging modality to quantify tissue stiffness. The aim of the study was to assess the feasibility and accuracy of US elastography for quantitative monitoring of thermal ablation and to determine the elasticity threshold predictive of coagulation necrosis. Methods A total of 29 in vivo thermal lesions were performed in pig livers with radiofrequency system. SWE and B-mode images were acquired simultaneously. Liver elasticity was quantified by using SWE data and expressed in kilopascal. After the procedure, pathologic analysis of treated tissues was compared with US images. The sensitivity and positive predictive value of the SWE maps of tissue elasticity were calculated and compared with the boundaries of the pale coagulation necrosis areas found at pathology. Results The liver mean elasticity values before and after thermal therapy were 6.4 ± 0.3 and 38.1 ± 2.5 kPa, respectively (P 20 kPa that actually developed coagulation necrosis) was 0.83. Conclusions Tissue areas with coagulation necrosis are significantly stiffer than the surrounding tissue. SWE permits the real-time detection of coagulation necrosis produced by radiofrequency and could potentially be used to monitor US-guided thermal ablation.

Ultrasound elastography in the head and neck. Part II. Accuracy for malignancy.

Ultrasound elastography (USE) describes a variety of ultrasound-based imaging techniques that measure tissue stiffness properties, and is currently under intense investigation for tissue characterization in several anatomic sites. This article summarizes the evidence regarding the accuracy of USE for malignancy in the head and neck. Currently, most published data pertains to small pilot studies with varied methodologies. Encouragingly, most studies have documented promising results for USE in terms of high accuracy for malignancy in thyroid nodules and cervical lymph nodes, which have surpassed conventional sonographic criteria. However, a minority of studies have documented opposite findings. USE seems to be suboptimal for salivary malignancies, and some evidence suggests that USE does not provide useful diagnostic information compared with conventional ultrasonography for miscellaneous neck masses. Further larger studies are required to validate these findings although, in view of the predominance of highly optimistic results for thyroid nodules and cervical lymph nodes, USE may become a useful ancillary technique in the routine diagnostic work-up of lesions in these tissues in the near future.

Impact of breast mass size on accuracy of ultrasound elastography vs. conventional B-mode ultrasound: a meta-analysis of individual participants

To conduct an individual patient data meta-analysis comparing the diagnostic performance of ultrasound elastography (USE) versus B-mode ultrasound (USB) across size ranges of breast masses. An extensive literature search of PubMed and other medical/general purpose databases from inception through August 2011 was conducted. Corresponding authors of published studies that reported a direct comparison of the diagnostic performance of USE using the elasticity score versus USB for characterisation of focal breast masses were contacted for their original patient-level data set. Summary diagnostic performance measures were compared for each test within and across three mass size groups (<10 mm, 10-19 mm, and >19 mm). The patient-level data sets were received from five studies, providing information on 1,412 breast masses. For breast masses <10 mm (n = 543; 121 malignant), the sensitivity/specificity of USE and USB were 76 %/93 % and 95 %/68 %, respectively. For masses 10-19 mm of size (n = 528; 247 malignant), sensitivity/specificity of USE and USB were 82 %/90 % and 95 %/67 %, respectively. For masses >19 mm of size (n = 325; 162 malignant), sensitivity/specificity of USE and USB were 74 %/94 % and 97 %/55 %, respectively. Regardless of the mass size, USE has higher specificity and lower sensitivity compared to USB in characterising breast masses. The performance of each of these two tests does not vary significantly by mass size.

Accuracy of Ultrasound Elastography in the Diagnosis of Thyroid Cancer in a Low-risk Population

Stiffness has been associated to malignancy in prostate and breast, as well as thyroid. Ultrasound elastography objectively measures tissue elasticity, and previous studies have described it as a high sensitivity and specificity technique for the detection of malignant thyroid nodules in high-risk populations. The aim was to assess the accuracy of elastography in a population with low risk of malignancy. 128 consecutive patients with nodular goiter were recruited. Elastography and ultrasound-guided fine-needle aspiration were performed. When malignancy was suspected by citology, surgery was recommended. Thyroid nodules were classified by elastography according the criteria described by Ueno, and an alternative classification. Sensitivity, specificity, predictive values, and odds ratio were calculated. Most patients were female, aged 56.1 year, with single nodule (52.0%) or multinodular goiter (45.6%), and a few thyroiditis (2.4%). The majority of nodules were mostly elastic. Fine-needle aspiration found 86% of benign nodules, 9.3% of indeterminate, and 4.7% possibly malignant. After surgery, 3 malignant nodules were confirmed, all of them being papillary carcinomas. All the malignant nodules were mostly elastic, as well as 75% of indeterminate nodules. Low values of sensitivity and specificity were found for elastic nodules being benign and hard nodules malignant. In a low-risk population for thyroid cancer, elastography lacks accuracy for the diagnosis of malignant nodules.

Application of Real-time Ultrasound Elastography in Diagnosing Benign and Malignant Thyroid Solid Nodules.

ObjectiveReal-time ultrasound elastography (US-E) is a helpful tool in diagnosing thyroid nodules. This study aims to evaluate thyroid solid nodules, to establish the accuracy of US-E in providing information on the nature of these nodules, and to assess the clinical value of elasticity scores (ES) and strain ratio (SR) in differentiating thyroid solid nodules and to explore its distribution characteristics using pathological analysis as reference.MethodsTraditional ultrasonography and US-E were performed on 131 thyroid solid nodules (99 benign ones and 32 malignant ones) in 120 patients (78 females and 41 males). Three radiologists evaluated the nodules based on a four-degree elasticity scoring system. The nodules were classified according to the ES as soft (ES 1-2) or hard (ES 3-4). The SR was calculated online.ResultsThe sensitivity and specificity of the ES for thyroid cancer diagnosis were 78% and 80%, respectively. SR values ≥ 2.9 used as a standard to distinguish benign from malignant nodules had a sensitivity of 87% and a specificity of 92%. The SR of the benign lesions was 1.64±1.37, which was significantly different from that of malignant lesions, which was 4.96±2.13 (P<0.01).ConclusionsBoth the ES and SR were higher in malignant nodules than those in benign ones. Real-time US-E was a useful index in the differential diagnosis of thyroid solid nodules. It can provide quantitative information on thyroid nodule characterization and improve diagnostic confidence.

Ultrasound speed varies in articular cartilage under indentation loading [Coresspondence

In ultrasound elastography, tissue strains are determined by localizing changes in ultrasound echoes during mechanical loading. The technique has been proposed for arthroscopic quantification of the mechanical properties of cartilage. The accuracy of ultrasound elastography depends on the invariability of sound speed in loaded tissue. In unconfined geometry, mechanical compression has been shown to induce variation in sound speed, leading to errors in the determined mechanical properties. This phenomenon has not been confirmed in indentation geometry, the only loading geometry applicable in situ or in vivo. In the present study, ultrasound speed during indentation of articular cartilage was characterized and the effect of variable sound speed on the strain measurements was investigated. Osteochondral samples (n = 7, diameter = 25.4 mm), prepared from visually intact bovine patellae (n = 7), were indented with a plane-ended ultrasound transducer (diameter = 5.6 mm, peak frequency: 8.1 MHz). A sequence of three compression tests (strain-rate = 10%/s, 2700-s relaxation) was applied using the mean strains of 2.2%, 4.5%, and 6.4%. Then, ultrasound speed during the ramp and stress-relaxation phases was determined using the time-of- flight technique. To investigate the role of cartilage structure and composition for sound speed in loaded articular cartilage, a sample-specific fibril-reinforced poroviscoelastic (FRPVE) finite element model was constructed and fitted to experimental mechanical data. Ultrasound speed in articular cartilage decreased significantly during dynamic indentation (p <; 0.05). The magnitude of the decrease in speed during indentation was related to the applied strain. However, the relative error in acoustically determined tissue strain was inversely related to the magnitude of true strain. The modeling results suggested that the compression-related variation in sound speed is controlled by changes in the collagen architecture during dynamic indentation. To conclude, variation in sound speed during dynamic indentation of articular cartilage may lead to significant errors in the values of measured mechanical parameters. Because the relative errors are inversely proportional to applied strain, higher strains should be used to minimize the errors in, e.g., in vivo measurements.

Thyroid nodules in acromegaly: The role of elastography

Introduction Ultrasound elastography (US-E) is a helpful tool for the diagnosis of thyroid cancer. In acromegaly, multinodular goiter is a common occurrence while the prevalence of thyroid cancer is still matter of debate. Our aims were to evaluate thyroid nodules in acromegaly and to assess the accuracy of US-E in providing information on their nature (benign vs. malignant) using cytological analysis as a reference. Materials and methods US-E was performed in 25 patients with acromegaly (active in 10 cases, medically controlled in 8, and cured by pituitary surgery in 7), each of whom had at least one solid thyroid nodule. A total of 90 nodules were classified according to the elastography scores (ES): ES1 and ES2 for soft nodules, ES3 and ES4 for an elastic lesions. FNAC was performed in 78.6% of the ES 4 lesions and 54.1% of the ES 3 nodules. Results Fourteen of the 90 nodules (15.5%) displayed an ES of 1, 25 (27.7%) an ES of 2, 37 (41.3%) an ES of 3, and 14 (15.5%) an ES of 4. The prevalence of hard nodules in patients with active acromegaly (68.9%) was greater than that observed in patients with cured (44.4%) or controlled (52.5%) acromegaly. The prevalence of hard nodules in the total series (56.7%) was higher than that reported in nonacromegalic goitrous subjects. All thyroid nodules subjected to FNAC were negative for malignant cells and follicular lesions. Discussion Acromegaly (particularly active forms) is associated with a high prevalence of stiff thyroid nodules that exceeds that observed in nonacromegalic patients with goiters (33.7%). However, these nodules were never malignant at cytology, and their firmness is probably due to fibrosis. US-E therefore appears to be of limited value for the diagnosis of thyroid cancer in patients with acromegaly.