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1.
Zhonghua Yi Xue Za Zhi ; 100(40): 3164-3168, 2020 Nov 03.
Artigo em Chinês | MEDLINE | ID: mdl-33142400

RESUMO

Objective: To evaluate the feasibility of transient elastography (FibroTouch) in obese children and to investigate the liver characteristics of obese children based on FibroTouch. Methods: Children (5-18 years of age) from the Guangzhou Women and Children's Medical Center were examined by FibroTouch. The fat attenuation parameter (FAP) was used to assess liver fat deposition, and liver stiffness measurement (LSM) was used to assess liver fibrosis. The children were divided into obesity group (n=67) and non-obesity group (n=139). The FAP, LSM, and their influencing factors were analysed in the obese group. Results: The total effective rate of FibroTouch in non-sedated children aged 5-18 years (n=229) was 97.8%. The FAP value 259.4 (235.9-275.5) dB/m in obese children was significantly higher than that in the control group 178.1 (168.7-195.6) dB/m, (Z=-10.586, P<0.001). The LSM value in obese children 5.9 (4.5-7.5) kPa was significantly higher than that in non-obese children 3.2 (2.3-4.1) kPa, (Z=-8.832, P<0.001). The proportion of liver fibrosis in obese group was 30%, and that of nonalcoholic fatty liver was 65.7%. Logistic regression analysis showed that BMI percentile (≥ 95%) was an independent factor for significant liver fibrosis (OR=1.267, 95%CI: 1.056-1.519, P=0.011) and nonalcoholic fatty liver disease (OR=1.248, 95%CI: 1.007-1.546, P=0.043). Conclusions: FibroTouch can be successfully applied to obese children. Fibrotouch can accurately evaluate the liver fibrosis and fat attenuation parameters in obese children. Obese children have higher FAP and LSM, which increase the risk of non-alcoholic fatty liver and liver fibrosis.


Assuntos
Técnicas de Imagem por Elasticidade , Hepatopatia Gordurosa não Alcoólica , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Fígado/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Obesidade
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1791-1794, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018346

RESUMO

Low dose computed tomography (LDCT) is the current gold-standard for lung cancer diagnosis. However, accuracy of diagnosis is limited by the radiologist's ability to discern cancerous from non-cancerous nodules. To assist with diagnoses, a 4D-CT lung elastography method is proposed to distinguish nodules based on tissue stiffness properties. The technique relies on a patient-specific inverse finite element (FE) model of the lung solved using an optimization algorithm. The FE model incorporates hyperelastic material properties for tumor and healthy regions and was deformed according to respiration physiology. The tumor hyperelastic parameters and trans-pulmonary pressure were estimated using an optimization algorithm that maximizes similarity between the actual and simulated tumor and lung image data. The proposed technique was evaluated using an in-silico study where the lung tumor elastic properties were assumed. Following that evaluation, the technique was applied to clinical 4D-CT data of two lung cancer patients. Results from the evaluation study show that the elastography technique recovered known tumor parameters with only 6% error. Tumor hyperelastic properties from the clinical data are also reported. Results from this proof of concept study demonstrate the ability to perform lung elastography with 4D-CT data alone. Advancements in the technique could lead to improved diagnoses and timely treatment of lung cancer.


Assuntos
Técnicas de Imagem por Elasticidade , Neoplasias Pulmonares , Algoritmos , Tomografia Computadorizada Quadridimensional , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1807-1810, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018350

RESUMO

In this paper, for the first time, a triple-mode scan using electromagnetic waves, in the shape of millimeter waves, and ultrasound waves, to obtain B-mode and quasistatic elastography images of a phantom of human breast tissues is shown. A homogeneous phantom composed of nontoxic, low-cost and easy-to-handle materials (i.e. water, oil, gelatin and dishwashing liquid) was produced, with an inclusion made of water and agar. These are intended to mimic, in terms of dielectric properties, healthy adipose tissues and neoplastic tissues, respectively. A millimeter-wave imaging prototype was used to scan the phantom, by implementing a linear synthetic array of 24 antennas with a central working frequency of 30 GHz. The phantom was then scanned using an ultrasound research system and a linear-array probe at 7 MHz, acquiring both B-mode and quasi-static elastography images. The millimeter-wave system showed an excellent ability to detect the target placed at about 1.4 cm depth. Also in the ultrasound case the inclusion was correctly detected as a hypoechoic, stiff mass. This first experimental findings show that millimeter-wave, ultrasound and elasticity imaging can be used jointly to detect tumor-like targets into phantoms mimicking healthy breast tissues. Thus, they provide promising preliminary results to further study the application of this multimodal approach in all those critical cases in which such complementary imaging techniques could be exploited for an enhanced tumor detection, based on tissues dielectric, acoustic and elastic properties.


Assuntos
Neoplasias da Mama , Técnicas de Imagem por Elasticidade , Neoplasias da Mama/diagnóstico por imagem , Elasticidade , Humanos , Imagens de Fantasmas , Ultrassonografia
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2007-2010, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018397

RESUMO

In this paper, we propose a novel framework for time delay estimation in ultrasound elastography. In the presence of high acquisition noise, the state-of-the-art motion tracking techniques suffer from inaccurate estimation of displacement field. To resolve this issue, instead of one, we collect several ultrasound Radio-Frequency (RF) frames from both pre- and post-deformed scan planes to better investigate the data statistics. We formulate a non-linear cost function incorporating all observation frames from both levels of deformations. Beside data similarity, we impose axial and lateral continuity to exploit the prior information of spatial coherence. Most importantly, we consider the continuity among the displacement estimates obtained from different observation RF frames. This novel continuity constraint mainly contributes to the robustness of the proposed technique to high noise power. We efficiently optimize the aforementioned cost function to derive a sparse system of linear equations where we solve for millions of variables to estimate the displacement of all samples of all of the incorporated RF frames simultaneously. We call the proposed algorithm GLobal Ultrasound Elastography using multiple observations (mGLUE). Our primary validation of mGLUE against soft and hard inclusion simulation phantoms proves that mGLUE is capable of obtaining high quality strain map while dealing with noisy ultrasound data. In case of the soft inclusion phantom, Signal-to-Noise Ratio (SNR) and Contrast-to-Noise Ratio (CNR) have improved by 75.37% and 57.08%, respectively. In addition, SNR and CNR improvements of 32.19% and 38.57% have been observed for the hard inclusion case.


Assuntos
Técnicas de Imagem por Elasticidade , Algoritmos , Imagens de Fantasmas , Razão Sinal-Ruído , Ultrassonografia
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2023-2026, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018401

RESUMO

Microwave ablation has become a common treatment method for liver cancers. Unfortunately, microwave ablation success is correlated with clinician's ability for proper electrode placement and assess ablative margins, requiring accurate imaging of liver tumors and ablated zones. Conventionally, ultrasound and computed tomography are utilized for this purpose, yet both have their respective drawbacks. As an alternate approach, electrode displacement elastography offers promise but is still plagued by decorrelation artifacts reducing lesion depiction and visualization. A recent filtering method, namely dictionary representation, has improved contrast-to-noise ratios without reducing delineation contrast. As a supplement to this recent work, this paper evaluates adaptations on this initial dictionary-learning algorithm and applies them to an EDE phantom and 15 in-vivo patient datasets. Two new adaptations of dictionary representations were evaluated, namely a combined dictionary and magnitude-based dictionary representation. When comparing numerical results, the combined dictionary representation algorithm outperforms the previous developed dictionary representation in signal-to-noise (1.54 dB) and contrast-to-noise (0.67 dB) ratios, while a magnitude dictionary representation produces higher noise levels, but improves visualized strain tensor resolution.


Assuntos
Técnicas de Imagem por Elasticidade , Neoplasias Hepáticas , Eletrodos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Imagens de Fantasmas
6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2027-2030, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018402

RESUMO

Ultrasound elastography is used to estimate the mechanical properties of the tissue by monitoring its response to an internal or external force. Different levels of deformation are obtained from different tissue types depending on their mechanical properties, where stiffer tissues deform less. Given two radio frequency (RF) frames collected before and after some deformation, we estimate displacement and strain images by comparing the RF frames. The quality of the strain image is dependent on the type of motion that occurs during deformation. In-plane axial motion results in high-quality strain images, whereas out-of-plane motion results in low-quality strain images. In this paper, we introduce a new method using a convolutional neural network (CNN) to determine the suitability of a pair of RF frames for elastography in only 5.4 ms. Our method could also be used to automatically choose the best pair of RF frames, yielding a high-quality strain image. The CNN was trained on 3,818 pairs of RF frames, while testing was done on 986 new unseen pairs, achieving an accuracy of more than 91%. The RF frames were collected from both phantom and in vivo data.


Assuntos
Técnicas de Imagem por Elasticidade , Algoritmos , Movimento (Física) , Redes Neurais de Computação , Imagens de Fantasmas
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2031-2034, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018403

RESUMO

Normalized cross-correlation (NCC) function used in ultrasound strain imaging can get corrupted due to signal decorrelation inducing large displacement errors. Bayesian regularization has been applied in an iterative manner to regularize the NCC function and to reduce estimation variance and peak-hopping errors. However, incorrect choice of the number of iterations can lead to over-regularization errors. In this paper, we propose the use of log compression of regularized NCC function to improve subsample estimation. Performance of parabolic interpolation before and after log compression of the regularized NCC function were compared in numerical simulations of uniform and inclusion phantoms. Significant improvement was achieved with the proposed scheme for lateral estimation results. For example, lateral signal-to-noise ratio (SNR) was 10 dB higher after log compression at 3% strain in a uniform phantom. Lateral contrast-to-noise ratio (CNR) was 1.81 dB higher with proposed method at 3% strain in inclusion phantom. No significant difference was observed in axial estimation due to presence of phase information and high sampling frequency. Our results suggest that this simple approach makes Bayesian regularization robust to over-regularization artifacts.


Assuntos
Compressão de Dados , Técnicas de Imagem por Elasticidade , Algoritmos , Teorema de Bayes , Ultrassonografia
8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2051-2054, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018408

RESUMO

Cancer is known to induce significant structural changes to tissue. In most cancers, including breast cancer, such changes yield tissue stiffening. As such, imaging tissue stiffness can be used effectively for cancer diagnosis. One such imaging technique, ultrasound elastography, has emerged with the aim of providing a low-cost imaging modality for effective breast cancer diagnosis. In quasi-static breast ultrasound elastography, the breast is stimulated by ultrasound probe, leading to tissue deformation. The tissue displacement data can be estimated using a pair of acquired ultrasound radiofrequency (RF) data pertaining to pre- and post-deformation states. The data can then be used within a mathematical framework to construct an image of the tissue stiffness distribution. Ultrasound RF data is known to include significant noise which lead to corruption of estimated displacement fields, especially the lateral displacements. In this study, we propose a tissue mechanics-based method aiming at improving the quality of estimated displacement data. We applied the method to RF data acquired from a tissue-mimicking phantom. The results indicated that the method is effective in improving the quality of the displacement data.


Assuntos
Técnicas de Imagem por Elasticidade , Algoritmos , Feminino , Humanos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Ultrassonografia Mamária
9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2055-2058, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018409

RESUMO

Many types of cancers are associated with changes in tissue mechanical properties. This has led to the development of elastography as a clinically viable method where tissue mechanical properties are mapped and visualized for cancer detection and staging. In quasi-static ultrasound elastography, a mechanical stimulation is applied to the tissue using ultrasound probe. Using ultrasound radiofrequency (RF) data acquired before and after the stimulation, the tissue displacement field can be estimated. Elasticity image reconstruction algorithms use this displacement data to generate images of the tissue elasticity properties. The accuracy of the generated elasticity images depends highly on the accuracy of the tissue displacement estimation. Tissue incompressibility can be used as a constraint to improve the estimation of axial and, more importantly, the lateral displacements in 2D ultrasound elastography. Especially in clinical applications, this requires accurate estimation of the out-of-plane strain. Here, we propose a method for providing an accurate estimate of the out-of-plane strain which is incorporated in the incompressibility equation to improve the axial and lateral displacements estimation before elastography image reconstruction. The method was validated using in silico and tissue mimicking phantom studies, leading to significant improvement in the estimated displacement.


Assuntos
Técnicas de Imagem por Elasticidade , Algoritmos , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Ultrassonografia
10.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2067-2070, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018412

RESUMO

Ultrasound data often suffers from an excessive amount of noise especially from deep tissue or in synthetic aperture imaging where the acoustic wave is weak. Such noisy data renders Time Delay Estimation (TDE) inaccurate in the context of ultrasound elastography. Herein, a novel two-step elastography technique is presented to ensure accurate TDE while dealing with noisy ultrasound data. In the first step, instead of one, we acquire several Radio-Frequency (RF) frames from both pre- and post-deformed positions of the tissue. We stack the frames collected from pre- and post-deformed planes in separate data matrices. Since each set is collected from the same level of tissue compression, we assume that the Casorati data matrices exhibit underlying low-rank structures, which are sought by taking the low-rank and sparse decomposition framework into account. This Robust Principal Component Analysis (RPCA) approach removes the random noise from the datasets as sparse error components. In the second step, we select one frame from each denoised ensemble and employ GLobal Ultrasound Elastography (GLUE) to perform the strain elastography. We call the proposed technique RPCA-GLUE. Our preliminary validation of RPCA-GLUE against simulation phantoms containing hard and soft inclusions proves its robustness to large noise. Substantial improvement in Signal-to-Noise Ratio (SNR) and Contrast-to-Noise Ratio (CNR) has also been observed. Simulation results show that in the presence of large noise, the proposed method substantially improves CNR from 5.0 to 22.6 in a soft inclusion and from 2.2 to 21.7 in a hard inclusion phantom.


Assuntos
Técnicas de Imagem por Elasticidade , Algoritmos , Imagens de Fantasmas , Ondas de Rádio , Razão Sinal-Ruído
11.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2071-2074, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018413

RESUMO

Ultrasound elastography is a non-invasive technique for detecting pathological alterations in tissue. It is known that pathological alteration of tissue often has a direct impact on its elastic modulus, which can be revealed using elastography. For estimating elastic modulus, we need to estimate both axial and lateral displacement accurately. Current state of the art elastography techniques provide a substantially less accurate lateral displacement field as compared to the axial displacement field. One of the most important factors in poor lateral estimation is a low sampling frequency in the lateral direction. In this paper, we use synthetic aperture beamforming to benefit from its capability of high sampling frequency in the lateral direction. We compare highly sampled data and focused line per line beam formed data by feeding them to our recently published elastography method, OVERWIND [1]. According to simulation and phantom experiments, not only the lateral displacement estimation is substantially improved, but also the axial displacement estimation is improved.


Assuntos
Técnicas de Imagem por Elasticidade , Módulo de Elasticidade , Imagens de Fantasmas
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2075-2078, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018414

RESUMO

Convolutional Neural Networks (CNN) have been extensively used for many computer vision applications including optical flow estimation. Although CNNs have been very successful in optical flow problem, they have been rarely used for displacement estimation in Ultrasound Elastography (USE) due to vast differences between ultrasound data and computer vision images. In USE, a main goal is to obtain the strain image which is the derivative of the axial displacement in axial direction; therefore, a very accurate displacement estimation is required. Radio Frequency (RF) data is needed to obtain accurate displacement estimation. RF data contains high frequency contents which cannot be downsampled without significant loss of information, in contrast to computer vision images. We propose a novel technique to utilize LiteFlowNet for USE. For the first time, we incorporate analytic signal to improve the quality of the displacement estimation. We show that this network with the designed inputs is more suitable for USE compared to more complex networks such as FlowNet2. The network is adopted to our application and it is compared with FlowNet2 and a state-of-the-art elastography method (GLUE). The results show that this network performs well and comparable to GLUE. Furthermore, not only this network is faster and has lower memory footprint compared to FlowNet2, but also it obtains higher quality strain images which makes it suitable for portable and real-time elastography devices.


Assuntos
Técnicas de Imagem por Elasticidade , Algoritmos , Redes Neurais de Computação , Imagens de Fantasmas , Ultrassonografia
13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2079-2083, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018415

RESUMO

The placenta is a vital organ for growth and development of the fetus. Shear Wave Absolute Vibro-Elastography (SWAVE) is a new elastography technique proposed to detect placenta disorders. Elastography involves applying a force on the tissue and measuring the resulting tissue deformation. All types of compression cause the tissue to expand in three directions given the biological tissues are nearly incompressible. Hence, 3D displacement estimation should lead to the most accurate elasticity reconstruction compared to the traditional 1D methods. Previous studies estimated 3D displacements over ultrasound volumes mostly for quasi-static compression to generate strain images. However, accurate displacement tracking of dynamic motion continues to be a challenge. In this work, a novel volumetric regularized algorithm, 3D GLobal Ultrasound Elastography (GLUE3D), is presented to estimate the 3D displacement over a volume of ultrasound data, following by a 3D Young's modulus reconstruction. The proposed method outperforms the previous 2D method over a volume and is compared with a 3D technique using phantom data for which the elasticity are provided by the values from magnetic resonance elastography on the same phantom and also the manufacturer reference numbers. We then present Young's modulus reconstruction results obtained from clinical data of placenta which shows more uniform elasticity maps compared to the traditional 1D displacement measurements over a volume of ultrasound data. Furthermore, the dependency of the elasticity values to the frequency is investigated in this study.


Assuntos
Técnicas de Imagem por Elasticidade , Módulo de Elasticidade , Elasticidade , Feminino , Humanos , Imagens de Fantasmas , Placenta/diagnóstico por imagem , Gravidez
14.
Zhonghua Yi Xue Za Zhi ; 100(39): 3075-3080, 2020 Oct 27.
Artigo em Chinês | MEDLINE | ID: mdl-33105958

RESUMO

Objective: To investigate the value of two-dimensional shear wave elastography (2D SWE) combined with clinical biochemical data in predicting posthepatoectomy liver failure (PHLF) in patients with hepatocellular carcinoma (HCC). Methods: A total of 274 HCC patients who underwent hepatectomy in Zhongshan Hospital Fudan University from January 2015 to January 2016 were retrospectively collected, including 235 males and 39 females, age 19-80 (56±11) years. All patients were confirmed to be HCC by postoperative pathology. The preoperative 2D SWE examination, laboratory examination results and intraoperative indicators were analyzed. According to the occurrence of PHLF after surgery, single factor analysis and multiple logistic regression analysis were performed on the above indicators to obtain a binary logistic regression model, and evaluate the diagnostic effect of the model on PHLF. In addition, 103 HCC patients from October 2019 to January 2020 were retrospectively collected as an external validation set, including 89 males and 14 females, age 23-80 (55±11) years old. Results: The liver stiffness measurement (LSM) obtained from 2D SWE, INR and Laminin (LN) were independent predictors of PHLF. The formula of prediction model PM=-15.451+0.095×LSM+11.7×INR+0.012×LN was obtained by combining above three factors. The area under the curve (AUC) of PHLF was 0.82, which was higher than that of end-stage liver disease model (MELD) score and Child-Pugh grading diagnosis of PHLF. The AUC of PHLF predicted by PM in the external validation group was 0.81. Conclusion: 2D SWE is helpful for clinicians to evaluate liver reserve function preoperatively and to predict the occurrence of PHLF in patients with HCC.


Assuntos
Carcinoma Hepatocelular , Técnicas de Imagem por Elasticidade , Falência Hepática , Neoplasias Hepáticas , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/diagnóstico por imagem , Criança , Feminino , Humanos , Falência Hepática/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
15.
Niger J Clin Pract ; 23(10): 1339-1344, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33047689

RESUMO

Backround: Ultrasonography is difficult to distinguish between endometrial pathologies and often requires curettage. ARFI (Acoustic Radiation Force-Based Elasticity Imaging) is a new ultrasonography elastography method. Using ARFI, it is possible to obtain information about the likelihood of the tissue benign or malignant. Aim: The aim of this study is to evaluate the contribution of ARFI to differentiate endometrial pathologies in hysterectomy specimens. Subjects and Methods: Our study was prospectively, January-May 2017, performed in randomly 45 cases of 41-91 years of age (mean 58.3 years) who have decided to have hysterectomy. Hysterectomy was performed for uterine prolapse and endometrial hyperplasia in elderly patients and menorrhagia in young patients. Pathology results were compared with ARFI values and endometrial thickness. ANNOVA test was used for the comparison of ARFI values. Results: Pathology revealed 14 cases of endometrial atrophy, 11 cases of proliferative phase, 10 cases of polyp, 6 cases of endometrial hyperplasia, and 4 cases of endometrium cancer. There is a statistically significant difference between mean ARFI values of endometrium, subendometrium, and myometrium of the groups (P < 0.05). There was a statistically significant difference between the mean endometrial thickness of the groups (P < 0.05). Conclusion: Endometrium ARFI contributes to the differential diagnosis of endometrial pathologies. Subendometrial and myometrial ARFI values decrease in polyps and increase in hyperplasia. Our study shows that the addition of subendometrium ARFI to gray-scale sonography before deciding on invasive procedures in endometrial pathologies may improve diagnostic accuracy. We concluded that further in vivo studies will establish the usefulness of this technique for preoperative diagnostic measures.


Assuntos
Hiperplasia Endometrial/cirurgia , Endométrio/diagnóstico por imagem , Histerectomia , Menorragia/cirurgia , Prolapso Uterino/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas de Imagem por Elasticidade/métodos , Hiperplasia Endometrial/patologia , Neoplasias do Endométrio , Feminino , Humanos , Menorragia/patologia , Pessoa de Meia-Idade , Pólipos/patologia , Ultrassonografia/métodos , Prolapso Uterino/patologia
16.
Medicine (Baltimore) ; 99(44): e23023, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33126387

RESUMO

The aim of this study is to investigate the accuracy of tumor size assessment by shear wave elastography (SWE) in invasive breast cancer and also evaluated histopathologic factors influencing the accuracy.A total of 102 lesions of 102 women with breast cancers of which the size was 3 cm or smaller were included and retrospectively analyzed. Tumor size on B-mode ultrasound (US) and SWE were recorded and compared with the pathologic tumor size. If tumor size measurements compared to pathological size were within ±3 mm, they were considered as accurate. The relationship between the accuracy and histopathologic characteristics were evaluated.The mean pathologic tumor size was 16.60 ±â€Š6.12 mm. Tumor sizes on SWE were significantly different from pathologic sizes (18.00 ±â€Š6.71 mm, P < 0.001). The accuracy of SWE (69.6%) was lower than that by B-mode US (74.5%). There was more size overestimation than underestimation (23.5% vs 6.9%) using SWE. Conversely, there was more size underestimation than overestimation (18.6% vs 6.9%) using B-mode US. The accuracy of SWE was associated with ER positivity (P = .004), PR positivity (P = .02), molecular subtype (P = .02), and histologic grade (P = .03). In the multivariate analysis, ER positivity (P = .002) and molecular subtype (P = .027) significantly influenced the accuracy of tumor size measurement by SWE.In conclusion, the accuracy of the tumor size measured with SWE was lower than that measured with B-mode US and SWE tends to overestimate the size. ER positivity and molecular subtype are significantly associated with the accuracy of SWE in tumor size assessment.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas de Imagem por Elasticidade , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos
17.
Medicine (Baltimore) ; 99(42): e22805, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33080756

RESUMO

The prevalence and impact of hepatic steatosis among patients with autoimmune hepatitis (AIH) is not well described.We conducted a cross-sectional study to determine the prevalence of hepatic steatosis in AIH patients and examined its relationship with hepatic fibrosis using vibration controlled transient elastography. Liver stiffness measurement (LSM), controlled attenuation parameter (CAP), gender, current age, and body mass index (BMI) were collected from 277 AIH patients. Hepatic steatosis was defined as CAP >263 db/m.The study participants were mostly female (82%) with an average age of 49 years and BMI 29.7 kg/m. Mean LSM was 12.5 (standard deviation 13.5) kPa and CAP was 244 (standard deviation 63) db/m. The prevalence of coexisting steatosis was 33.2%, and steatosis did not correlate with LSM (r = 0.05, P = .46). In this study, only gender (females with 31% lower LSM on average compared to males, P = .001) and BMI (each unit increase of BMI resulted in a 1.48% increase on average LSM, P = .01) correlated with LSM. Male gender had significant association with increased LSM, after controlling for age, BMI, and CAP (P = .001).This exploratory study using noninvasive vibration controlled transient elastography revealed hepatic steatosis is highly prevalent in patients with AIH but not associated with liver fibrosis.


Assuntos
Técnicas de Imagem por Elasticidade , Fígado Gorduroso/diagnóstico , Hepatite Autoimune/complicações , Índice de Massa Corporal , Estudos Transversais , Fígado Gorduroso/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais
18.
Z Gastroenterol ; 58(9): 847-854, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32947630

RESUMO

BACKGROUND: The aim of our study is to analyze viscosity characteristics of focal liver lesions (FLLs) and the diagnostic performance of shear wave dispersion (SWD) in differentiating benign and malignant FLLs. METHODS: Between January 2018 and April 2018, 58 consecutive patients (median age 57, age range 21-74 years, 37 males) with 58 FLLs located on the right lobe of liver were prospectively studied. The Aplio i900 series diagnostic ultrasound system (Canon Medical systems) equipped with a curvilinear PV1-475BX transducer (1-8 MHz) was used. SWD slope and viscosity measurements were expressed as mean ± standard deviation for both liver tumors and background liver parenchyma. Histopathological results after surgery were regarded as the gold standard for diagnosis. RESULTS: Final diagnosis included 40 cases of malignant and 18 cases of benign FLLs. The mean viscosity value were 14.78 ±â€Š1.86 m/s/kHz for hepatocellular carcinoma (n = 30), 14.81 ±â€Š2.35 m/s/kHz for liver metastasis lesions (n = 10), 13.23 ±â€Š1.31 m/s/kHz for hemangioma (n = 13), and 13.67 ± 2.72 m/s/kHz for focal nodular hyperplasia (n = 5). Malignant FLLs showed higher mean viscosity values (14.79 ±â€Š3.15 m/s/KHz) than benign FLLs (13.36 ±â€Š2.76 m/s/KHz) (p < 0.05). The best performing cut-off value of lesion viscosity was 13.15 m/s/kHz (sensitivity 83.3 %; specificity 56.5 %; area under the curve (AUC) 0.71) for malignancy) (p < 0.05). CONCLUSIONS: The analysis of SWD slope and liver viscosity parameters provide additional viscoelastic information about FLLs before operation.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Fígado/diagnóstico por imagem , Adulto , Idoso , Meios de Contraste , Diagnóstico Diferencial , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Ultrassonografia , Viscosidade , Adulto Jovem
19.
Zhonghua Yan Ke Za Zhi ; 56(9): 676-680, 2020 Sep 11.
Artigo em Chinês | MEDLINE | ID: mdl-32907300

RESUMO

Objective: To explore the role of the scoring and strain ratio methods of ultrasonic elastography in the differential diagnosis of choroidal melanoma and choroidal hemangioma. Methods: A cross-sectional study. Twenty-five patients (25 eyes) with choroidal melanoma treated in the Department of Ophthalmology, Beijing Tongren Hospital, Capital Medical University from July to October 2016 were included in this study. There were 13 males and 12 females, with an average age of (48±12) years old. Twenty-five patients (25 eyes) with choroidal hemangioma treated in the same period were selected for differential diagnosis, including 12 males and 13 females, with an average age of (37±13) years. The lesions were examined by ultrasound elastography and scored, and the strain ratio of the tumor to the orbital tissue was measured. Two independent sample t test was used to compare the difference in the elasticity score and strain ratio between choroidal melanoma and choroidal hemangioma. The sensitivity, specificity and area under the receiver operating characteristic (ROC) curve were calculated to analyze the value of the two methods in the differential diagnosis of choroidal melanoma and choroidal hemangioma. Results: The elastography score of choroidal melanoma was (3.48±0.77) points, including 2 points in 3 cases, 3 points in 8 cases, 4 points in 13 cases, and 5 points in 1 case. The elastography score of hemangioma was (2.28±0.46) points, including 2 points in 18 cases and 3 points in 7 cases. The difference in the elasticity score between patients with the two kinds of tumors was statistically significant (t=6.694, P<0.01). The strain ratio was 42.97±15.83 and 12.21±9.24 in the patients with choroidal melanoma and choroidal hemangioma, respectively, and the difference was statistically significant (t=8.392, P<0.01). Using 3 points as the diagnostic critical point of the elastography score, the sensitivity was 88.0%, the specificity was 72.0%, and the area under the ROC curve was 0.80 (95% cofidence interval: 0.663 to 0.900, P<0.01). Using 21.67 as the diagnostic critical point of the strain ratio, the sensitivity was 92.0%, the specificity was 92.0%, and the area under the ROC curve was 0.92 (95% cofidence interval: 0.808 to 0.978, P<0.01). Conclusions: Ultrasound elastography plays a role in the differential diagnosis of choroidal melanoma and choroidal hemangioma. The differential diagnostic value of the strain ratio method is higher than the scoring method. (Chin J Ophthalmol, 2020, 56: 676-680).


Assuntos
Técnicas de Imagem por Elasticidade , Hemangioma , Melanoma/diagnóstico por imagem , Adulto , Estudos Transversais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade , Ultrassom , Adulto Jovem
20.
Clinics (Sao Paulo) ; 75: e1670, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32935822

RESUMO

OBJECTIVES: Acoustic radiation force impulse (ARFI) elastography, the aspartate aminotransferase-to-alanine aminotransferase ratio (AAR), aspartate aminotransferase-to-platelet ratio index (APRI), and the fibrosis-4 (FIB-4) index are widely used to assess liver fibrosis. However, efficacies of these methods in the evaluation of hepatic functional reserve remain unclear. In this study, we investigated the relationship between ARFI elastography combined with either AAR, APRI, or FIB-4 index and Child-Pugh (CP) class for the evaluation of hepatic functional reserve in patients with chronic hepatitis B (CHB)-related cirrhosis. METHODS: The shear wave velocities of 104 patients with clinically confirmed CHB-related cirrhosis were determined using the ARFI; and clinical serum markers (e.g. ALT, AST, PLT) were used to calculate the AAR, APRI, and FIB-4 index. Cirrhosis patients were scored according to their CP class. The ARFI, AAR, APRI, and FIB-4 index were compared with the CP class. The efficacy of each indicator in diagnosis was analyzed using the receiver operating characteristic (ROC) curve and the ARFI combined with either the AAR, APRI, or FIB-4 index, which is used to predict decompensated cirrhosis. RESULTS: No significant differences were observed in gender and age among CP classes A, B, and C patients (p>0.05). The ARFI values and the AAR, APRI, and FIB-4 index of patients with CP classes A, B, and C were significantly different (p<0.05). With an increasing CP class, the ARFI, AAR, APRI, and FIB-4 values increased. The correlation between the ARFI and the CP class was stronger than that between the AAR, APRI, and FIB-4 index and the CP class. The area under the ROC curve for the diagnosis of decompensated cirrhosis using the ARFI was 0.841, which was higher than that for the AAR, APRI, and FIB-4 index. According to the area under the curve results, no significant differences were found when the ARFI was combined with either the AAR, APRI, or FIB-4 index and when the ARFI alone was used. CONCLUSIONS: The ARFI value has a strong correlation with the CP class. Therefore, ARFI elastography complements CP class in the assessment of the hepatic functional reserve in patients with CHB-related cirrhosis.


Assuntos
Acústica , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Técnicas de Imagem por Elasticidade , Cirrose Hepática/patologia , Biomarcadores/sangue , Biópsia , Criança , Técnicas de Imagem por Elasticidade/métodos , Feminino , Humanos , Fígado/patologia , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico por imagem , Masculino , Valor Preditivo dos Testes , Curva ROC , Sensibilidade e Especificidade , Índice de Gravidade de Doença
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