This article reviews the clinical applications of current ultrasound elastography methods in non-hepatic conditions including thyroid nodules, prostate cancer, chronic kidney disease, solid renal lesions, pancreatic lesions, and deep vein thrombosis. Pathophysiology alters tissue mechanical properties via ultrastructural changes including fibrosis, increased cellularity, bleeding, and necrosis, creating a target biomarker, which can be imaged qualitatively or quantitatively with US elastography. US elastography methods can add information to conventional US methods and improve the diagnostic performance of conventional US in a range of disease processes.
BACKGROUND: There currently is a need for a non-invasive measure of renal fibrosis. We aim to explore whether shear wave elastography (SWE)-derived estimates of tissue stiffness may serve as a non-invasive biomarker that can distinguish normal and abnormal renal parenchymal tissue.
METHODS: Participants with CKD (by estimated GFR) and healthy volunteers underwent SWE. Renal elasticity was estimated as Young's modulus (YM) in kilopascals (kPa). Univariate Wilcoxon rank-sum tests were used.
RESULTS: Twenty-five participants with CKD (median GFR 38 mL/min; quartile 1, quartile 3 28, 42) and 20 healthy controls without CKD underwent SWE performed by a single radiologist. CKD was associated with increased median YM (9.40 [5.55, 22.35] vs. 4.40 [3.68, 5.70] kPa; p = 0.002) and higher median intra-subject inter-measurement estimated YM's variability (4.27 [2.89, 9.90] vs. 1.51 [1.21, 2.05] kPa; p < 0.001).
CONCLUSIONS: SWE-derived estimates of renal stiffness and intra-subject estimated stiffness variability are higher in patients with CKD than in healthy controls. Renal fibrosis is a plausible explanation for the observed difference in YM. Further studies are required to determine the relationship between YM, estimated renal stiffness, and renal fibrosis severity.
The aim of the paper is to provide a comprehensive overview on the applications of real time sonoelastography (SE) in the diagnosis of superficial lymphadenopathy. Some technical aspects of performing SE are presented as a preamble. The typical appearance of benign and malignant nodes is illustrated. The paper discusses and depicts the various elastographic scores in use. It also provides a critical appraisal of the relative strain ratio (SR) or stiffness index. Shear wave elastography, as a novel technique, is mentioned. In conclusion, hardness on more than 50% of the node surface or SR > 1.5 is fair to good indicators of malignancy. Work is still needed both to fully understand the various appearance of disease and to standardize the application.
PURPOSE: To compare and determine the level of agreement of findings at conventional B-mode ultrasonography (US) and sonoelastography of the Achilles tendon with findings at histologic assessment.
MATERIALS AND METHODS: This study was conducted with the approval of the institutional review boards, and all cadavers were in legal custody of the study institution. Thirteen Achilles tendons in 10 cadavers (four male, six female; age range, 70-90 years) were examined with B-mode US and sonoelastography. B-mode US grading was as follows: Grade 1 indicated a normal-appearing tendon with homogeneous fibrillar echotexture; grade 2, a focal fusiform or diffuse enlarged tendon; and grade 3, a hypoechoic area with or without tendon enlargement. Sonoelastography grading was as follows: Grade 1 indicated blue (hardest) to green (hard); grade 2, yellow (soft); and grade 3, red (softest). Twenty-five biopsy specimens from representative lesions of the middle and distal thirds of the Achilles tendons were evaluated histologically. The concordance of B-mode US grading compared with sonoelastographic grading was assessed by using κ analysis.
RESULTS: With B-mode US and sonoelastography, all 11 tendon thirds of histologically normal tendons were verified as normal (grade 1). Sonoelastography depicted 14 of 14 (100%) tendon thirds with histologic degeneration (grade 2 or 3), whereas B-mode US could depict only 12 of 14 (86%) lesions (grade 2 or 3). Only moderate agreement between B-mode US and sonoelastography was seen (κ = 0.52, P < .001).
CONCLUSION: Sonoelastography might help predict signs of histopathologic degeneration of Achilles tendinosis, potentially more sensitively than B-mode US.
BACKGROUND: Sonoelastography has been used to differentiate malignant from benign lesions in numerous types of tissues including breast, prostate, liver, blood vessels, thyroid, musculoskeletal structures, and salivary glands.
PURPOSE: To evaluate the efficacy and application of real-time qualitative sonoelastography in the differentiation of benign and malignant focal parotid gland lesions.
MATERIAL AND METHODS: A total of 75 patients (36 boys/men, 39 girls/women; age range, 10-83 years) with 81 lesions were evaluated prospectively by sonoelastography performed and interpreted by two expert radiologists. The results of these experts classification and scoring of lesions according to relative stiffness of the mass were compared with each other and with histopathological findings. The interpretation of sonoelastography scores of 1-4 were as follows: 1, soft; 2, mostly soft; 3, mostly stiff; and 4, stiff.
RESULTS: The kappa statistic of 0.508 (P < 0.001) indicated moderate agreement between the two radiologists. The sonoelastography scores correctly diagnosed 30 of 49 benign tumors (sensitivity, 61.2%) and 19 of 32 malignant tumors (specificity, 59.4%). The area under the receiver-operating characteristic curve was 0.603. The diagnostic value of sonoelastography for evaluating pleomorphic adenomas, Warthin tumors, adenoid cystic carcinoma, and high-grade tumors was low, whereas the diagnostic rates for low-grade tumors such as mucoepidermoid carcinoma, acinic cell carcinoma, and metastases of basal cell carcinoma were better with sonoelastography.
CONCLUSION: Although sonoelastography seems to be promising in the differentiating of low-grade malignancies, the primary role of radiology is currently limited to determination of localization, size, and morphology of parotid tumors.
OBJECTIVES: Our aim was to investigate whether the use of a qualitative elasticity scoring method by sonoelastography is beneficial for management of salivary gland masses.
METHODS: Thirty-six patients with salivary gland masses (30 parotid and 6 sub-mandibular) were prospectively included in this study. For each lesion, B-mode sonographic and sonoelastographic images were obtained. Elasticity scores were determined by a 4-point scoring method. Differences among scores for benign and malignant masses were assessed by the Mann-Whitney U test. Qualitative variables were compared by the Pearson χ² test. The findings were compared with histopathologic diagnoses.
RESULTS: The score values of 28 benign masses ranged from 1 to 4, whereas the values of 8 malignant masses ranged from 2 to 4. The mean scores ± SD were 2.25 ± 0.92 for benign lesions and 3.0 ± 0.75 for malignant lesions (P < .05). When we considered scores 1 and 2 as benign and scores 3 and 4 as malignant, 10 false-positive results were determined by the 4-point scoring method, and 64.2% of benign masses were diagnosed.
CONCLUSIONS: Sonoelastography might be regarded as another sonographic parameter for management of salivary gland masses in terms of detecting benign masses.
CONTEXT: Pathology changes the consistency of the tissues.
OBJECTIVE: To prospectively assess the accuracy of per-abdominal US elastography in the form of acoustic radiation force impulse--virtual touch tissue quantification (ARFI-VTQ) and eSie touch elasticity imaging in characterizing and differentiating inflammatory pancreatic diseases.
PATIENTS: One-hundred and 66 patients from among the patients that visited the Asian Institute of Gastroenterology, Hyderabad, India, during the period April 2009 to December 2010, for master health check-up, blood donation and those with pancreatic pathology.
SETTING: Based on the clinical symptomatic criteria and diagnostic imaging findings, the patients were divided into normal, chronic and acute, or acute resolving, pancreatitis group.
MAIN OUTCOME MEASURES: The ultrasound based ARFI-VTQ and eSie touch elasticity imaging techniques were applied.
DESIGN: Prospective single-center study.
RESULTS: The mean ARFI-VTQ values were 1.28 m/s, 1.25 m/s and 3.28 m/s for the normal, chronic and acute pancreas, respectively. The eSie touch gray scale and color elastograms were light gray and purple-greenish, respectively for both normal and chronic pancreas, while for acute pancreas the elastograms were dark black on the gray scale and orange to red on color scale.
CONCLUSION: Both the ARFI-VTQ and eSie touch elasticity imaging techniques may be successfully adopted in order to diagnose acute pancreatitis, to assess extent of inflammation (whether focal or diffuse), to assess peripancreatic edema, to identify presence of necrotic areas and early pseudocyst formation, to early diagnose acute recurrent attacks and to monitor patient's response to treatment.
OBJECTIVE: The aim of this study is to explore the diagnostic value of sonoelastography for the differentiation between benign and malignant superficial lymph nodes of the neck. In this respect the utility of an original scoring system was explored.
MATERIAL AND METHOD: Over a period of 30 months the patients examined routinely for the assessment of superficial lymph nodes of the neck were recorded in a data base containing grey-scale, Doppler and sonoelastographic information and images. The sonoelastographic images of 30 benign and 39 malignant lymph nodes were assessed. The images were scored according to a new, eight pattern scoring system proposed by our group. Interobserver agreement and area under the ROC curve (AUROC) for the differentiation between benign vs. malignant and benign vs. metastatic nodes were analyzed.
RESULTS: The analysis of the interobserver agreement for the investigated score provided a weighted Kappa = 0.687, 95%CI [0.572 to 0.802] and standard error = 0.059. In the differentiation benign - malignant, the AUROC was 0.846, with sensitivity of 66.67% and specificity of 96.67% for score > 3. In the differentiation between benign and metastasis, the same criterion provided an AUROC of 0.855, with sensitivity of 71.43 and specificity of 96.67%.
CONCLUSIONS: Our study suggests that applying the proposed score provides good interobserver agreement. The score also provided very good specificity and reasonable sensitivity in the differentiation between malignant and benign lymph nodes in the neck.
OBJETIVO: El objetivo de este estudio fue evaluar la utilidad de la elastografía por ultrasonido y las imágenes MicroPure en el diagnóstico diferencial de los nódulos tiroideos benignos y malignos.
Sujetos y métodos: Un total de 74 pacientes consecutivos (65 mujeres y nueve hombres, rango de edad, 21-80 años; media [± DE] de edad, 51 ± 12,7 años) con nódulos tiroideos, que fueron remitidos para biopsia por aspiración con aguja fina por las clínicas de endocrinología o cirugía general, se examinaron de forma prospectiva mediante ecografía en modo B, la elastografía por ultrasonido, y proyección de imagen MicroPure. Se calculó la relación valor de deformación (índice de deformación) de los nódulos tiroideos. Los pacientes con finas agujas resultados de la biopsia por aspiración malignas o intermedios se sometieron a cirugía de tiroides.
No se encontraron utilizando imágenes MicroPure, 17 de 65 nódulos tiroideos benignos (26,6%) y tres de los nueve nódulos tiroideos malignos (33,3%) para contener microcalcificaciones: RESULTADOS. La sensibilidad, especificidad, valor predictivo negativo, valor predictivo positivo y el índice de exactitud de las imágenes MicroPure fueron 42,9%, 80,6%, 93,1%, 18,8% y 77%, respectivamente. Mediante el uso de análisis de funcionamiento del receptor característica, el mejor punto de corte (2.31) se calculó (área bajo la curva, 0,87; p <0,001). La tasa de sensibilidad, especificidad, valor predictivo negativo, valor predictivo positivo y la exactitud de los valores de índice de deformación fueron 85,7%, 82,1%, 98,2%, 33,3%, y 82,4%, respectivamente, cuando se usó el mejor punto de corte de 2,31 (p = 0,001). El valor de p (x = maligna) fue de 0,96 para un valor de índice de tensión superior a 2,31.
CONCLUSIÓN: Este estudio preliminar indicó que la elastografía por ultrasonido y las imágenes MicroPure se pueden utilizar para la diferenciación de los nódulos tiroideos benignos y malignos.
BACKGROUND: To investigate the value of ultrasound elastography (UE) in the differentiation between benign and malignant enlarged cervical lymph nodes (LNs).
METHODS: B-mode ultrasound, power Doppler imaging and UE were examined to determine LN characteristics. Two kinds of methods, 4 scores of elastographic classification and a strain ratio (SR) were used to evaluate the ultrasound elastograms.
RESULTS: The cutoff point of SR had high utility in differential diagnosis of benign and malignant of cervical lymph nodes, with good sensitivity, specificity and accuracy.
CONCLUSION: UE is an important aid in differential diagnosis of benign and malignant cervical LNs.
This article reviews the clinical applications of current ultrasound elastography methods in non-hepatic conditions including thyroid nodules, prostate cancer, chronic kidney disease, solid renal lesions, pancreatic lesions, and deep vein thrombosis. Pathophysiology alters tissue mechanical properties via ultrastructural changes including fibrosis, increased cellularity, bleeding, and necrosis, creating a target biomarker, which can be imaged qualitatively or quantitatively with US elastography. US elastography methods can add information to conventional US methods and improve the diagnostic performance of conventional US in a range of disease processes.
