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排序方式: 共有699条查询结果,搜索用时 15 毫秒
1.
Orhan Görgülü Feride Fatma Görgülü Ayşe Selcan Koç 《Revista brasileira de otorrinolaringologia (English ed.)》2021,87(3):338-345
IntroductionOnly 5%–15% of thyroid surgical specimens are reported as malignant. Most of the operations are performed due to suspicion of malignancy as a result of fine needle aspiration biopsy but invasiveness, non-diagnostic results and potential repeat biopsies are disadvantages of fine needle aspiration biopsy.ObjectiveThe aim of this study was to investigate the effectiveness of simultaneously using both the strain ratio and elasticity score in the differential diagnosis of thyroid nodules, as well as to assess the compatibility of these two methods.MethodsA total of 144 nodules were included in the study. The final histopathologic diagnosis was used as the reference standard. The area under the curve sensitivity, specificity, and cut-off values of the strain ratio and elasticity score were determined using receiver operating characteristic curve analysis. The compatibility and comparison of strain ratio and elasticity score were also performed.ResultsTwenty eight nodules (19.4%) were malignant. The strain ratio and elasticity score results were found to be significantly successful in predicting thyroid malignancy (p < 0.001 for both). Moreover, the area under the curve for the strain ratio and elasticity score were found to be 0.944 and 0.960, respectively. The diagnostic accuracy of the elasticity score was found to be superior to that of the strain ratio, but this difference was not statistically significant (p = 0.456). When the compatibility of the strain ratio and elasticity score was examined, the two evaluations were revealed to be statistically consistent with each other (Kappa = 0.767; p < 0.001). When the strain ratio and the elasticity score were used together, the specificity of capturing the correct diagnosis increased from 84.5% to 93.1%.ConclusionWhen the strain ratio an elasticity score were used together for the differential diagnosis of thyroid nodules, more accurate results were obtained. Thus, combining both methods may be a promising alternative to fine needle aspiration biopsy in order to prevent unnecessary surgical interventions for suspected thyroid nodules. 相似文献
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Hobson MA Madsen EL Frank GR Jiang J Shi H Hall TJ Varghese T 《Ultrasound in medicine & biology》2008,34(10):1622-1637
Two anthropomorphic uterine phantoms were developed that allow assessment and comparison of strain imaging systems adapted for use with saline-infused sonohysterography (SIS). Tissue-mimicking (TM) materials consist of dispersions of safflower oil in gelatin. TM fibroids are stiffer than the TM myometrium/cervix, and TM polyps are softer. The first uterine phantom has 3-mm-diameter TM fibroids distributed randomly in TM myometrium. The second uterine phantom has a 5-mm and 8-mm spherical TM fibroid, in addition to a 5-mm spherical and a 12.5-mm-long (medicine capsule-shaped) TM endometrial polyp protruding into the endometrial cavity; also, a 10-mm spherical TM fibroid projects from the serosal surface. Strain images using the first phantom show the stiffer 3-mm TM fibroids in the myometrium. Results from the second uterine phantom show that, as expected, parts of inclusions projecting into the uterine cavity will appear very stiff, whether they are stiff or soft. Results from both phantoms show that although there is a five-fold difference in the Young's moduli values, there is not a significant difference in the strain in the transition from the TM myometrium to the TM fat. These phantoms allow for realistic comparison and evolution of SIS strain imaging techniques and can aid clinical personnel to develop skills for SIS strain imaging. 相似文献
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Huan Wee Chan Ronit Pressler Christopher Uff Roxanna Gunny Kelly St Piers Helen Cross Jeffrey Bamber Neil Dorward William Harkness Aabir Chakraborty 《Epilepsia》2014,55(4):e30-e33
Focal symptomatic epilepsy is the most common form of epilepsy that can often be cured with surgery. A small proportion of patients with focal symptomatic epilepsy do not have identifiable lesions on magnetic resonance imaging (MRI). The most common pathology in this group is type II focal cortical dysplasia (FCD), which is a subtype of malformative brain lesion associated with medication‐resistant epilepsy. We present a patient with MRI‐negative focal symptomatic epilepsy who underwent invasive electrode recordings. At the time of surgery, a novel ultrasound‐based technique called ShearWave Elastography (SWE) was performed. A 0.5 cc lesion was demonstrated on SWE but was absent on B‐mode ultrasound and 3‐T MRI. Electroencephalography (EEG), positron emission tomography (PET), and magnetoencephalography (MEG) scans demonstrated an abnormality in the right frontal region. On the basis of this finding, a depth electrode was implanted into the lesion. Surgical resection and histology confirmed the lesion to be type IIb FCD. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here . 相似文献
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《Diagnostic and interventional imaging》2014,95(9):813-824
PurposeTo determine the diagnosis performance of shear wave elastography in the differentiation of benign and malignant breast lesions and the factors influencing the elasticity values. To suggest an appropriate management of breast lesions using the ultrasound-elastography combination.Patients and methodsMonocentric retrospective study of 167 breast lesions classified by conventional ultrasound as BI-RADS category 3 or higher that underwent an elastography study and histological analysis.ResultsThe analysis of qualitative parameters, according to the classification established in this study, allows us to obtain a sensitivity of 91.1% and a specificity of 92.3%. These values are very close to or better than the quantitative parameters Emax and Emean. Different Emax thresholds values were established based on the long axis of the lesion and its palpable character, which appeared to be significant factors influencing elasticity. The management of breast lesions by combining ultrasound and elastography, as proposed here, allows us to keep the sensitivity of an ultrasound (96%), while doubling its specificity (86.2% versus 43.1%).ConclusionWith the complementary nature of their performance, the combination of conventional ultrasound and shear wave elastography can improve the management of breast lesions. The qualitative classification proposed appears to be relevant assistance in lesion characterization. 相似文献
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Intravascular ultrasound (IVUS) elastography is an imaging technique that obtains the local mechanical properties of the artery wall and atherosclerotic plaques through strain measurements using IVUS. Knowledge of these mechanical properties may provide crucial information that can help in estimating plaque composition and its vulnerability. Here, we present a new method to estimate the transverse strain tensor of the arterial wall based on nonrigid image registration using IVUS images. This method registers a pair of images acquired at a vessel site under different levels of luminal pressure. The 2-D displacement field in the vessel cross-section is estimated from image registration; then the displacement field is used to calculate the 2-D local strain tensor. From the strain tensor, the strain in any direction in the cross-section can be obtained; here, the radial and circumferential strain distributions are presented. This strain estimation method has been validated with synthetic motion IVUS images and evaluated using the IVUS images of a polyvinyl alcohol cryogel phantom. The accuracy of the estimated strain and the ability of the method to overcome IVUS system noise are demonstrated. 相似文献
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实时超声弹性成像评估物体硬度的实验研究 总被引:14,自引:4,他引:14
目的探讨实时超声弹性成像评估不同物体硬度的有效性及影响因素。方法选择5种不同硬度的物体,分别放置于3种介质中,以超声弹性成像评估其硬度。改变物体大小及放置深度,以观察对弹性分级的影响。弹性图像根据物体不同硬度分为5级。结果随着物体硬度的增加,弹性分级数亦增加。物体大小在一定范围内(≥5mm)对弹性分级无明显影响,而当物体过小时,可造成弹性分级的误判。随着物体放置深度的增加,弹性分级数也相应增加。结论实时超声弹性成像能较有效地分辨不同硬度的物体。 相似文献
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目的观察常规超声、超声弹性成像以及18F-FDG PET/CT对乳腺良恶性病变的诊断价值。方法回顾性2019年1月至2020年2月在我院治疗的67例乳腺病变患者的临床资料。分析其影像学资料,比较常规超声、超声弹性成像以及18F-FDG PET/CT检查结果与病理学检查结果的一致性;以病理学检查为标准,比较三种检查对乳腺良恶性病变的诊断效能及诊断价值。结果18F-FDG PET/CT检查结果与病理学检查结果的一致性(Kappa=0.906)大于常规超声(Kappa=0.566)和超声弹性成像(Kappa=0.662);18F-FDG PET/CT鉴别乳腺良恶性病变的灵敏度及特异度高于常规超声,准确率高于常规超声、超声弹性成像(P<0.05);经ROC曲线分析得,18F-FDG PET/CT鉴别乳腺良恶性病变的AUC为0.966,大于常规超声(0.787)及超声弹性成像(0.838,P<0.05)。结论18F-FDG PET/CT鉴别乳腺良恶性病变的准确率高于常规超声、超声弹性成像,且其具有较高的诊断价值。 相似文献
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子宫肌瘤和子宫腺肌瘤均为女性常见的良性疾病,对二者正确的鉴别诊断对治疗方案的建立以及手术方式的选择具有重要意义。本文就各种超声检查技术在子宫肌瘤和子宫腺肌瘤的鉴别诊断中的研究进展进行综述。 相似文献