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1.
Background: Breast cancer (BC) is the most common malignant tumor in women, and its morbidity and mortality are
increasing each year, due to the lack of specific clinical symptoms in the early stage of BC, and the lack of diagnostic
methods for early breast cancer. Therefore, identifying an effective diagnostic method for early BC has become urgent.
Materials and Methods: Breast lesions with a histological diagnosis that were examined by ultrasonic elastography
(UE) in our department from June 2020 to December 2021 were reviewed. qRT-PCR was performed to measure
the expression levels of miR-144-5p and miR-26b-5p in the plasma of patients with BC. The receiver operating characteristics (ROC) curve and area under the curve (AUC) were used to investigate the potential diagnostic value of miR-
144-5p, miR-26b-5p and the elastographic score in BC. Results: The ultrasonic elastography score(UES) was found to
be significantly upregulated in BC compared with that in benign breast lesions, and the AUC, sensitivity and specificity
were 0.809, 0.717 and 0.806 for distinguishing BC from benign breast lesions, respectively. miR-144-5p and miR-26b-
5p were found to be upregulated in the plasma of BC patients, and miR-144-5p+miR-26b-5p had 0.781 sensitivity and
0.780 specificity for the diagnosis of BC. Furthermore, we found that the diagnostic performance of miR-144-5p and
miR-26b-5p combined with UES for BC had 0.913 sensitivity and 0.890 specificity. Conclusions: The combination of
plasma miR-144-5p, miR-26b-5p and UES has a very high clinical application value for the early detection of BC. 相似文献
2.
Breast Elastography: How to Perform and Integrate Into a “Best-Practice” Patient Treatment Algorithm
Breast elastography has been available for more than 15 years but is not widely incorporated into clinical practice. Many publications report extremely high accuracy for various breast elastographic techniques. However, results in the literature are extremely variable. This variability is most likely due to variations in technique, a relatively steep learning curve, and variability in methods between vendors. This article describes our protocol for performing breast elastography using both strain elastography and shear wave elastography, which produces high sensitivity and specificity. Additionally, we will describe the most commonly known false-positive and false-negative lesions as well as how to detect them. 相似文献
3.
PNPLA3 gene polymorphism and response to lifestyle modification in patients with nonalcoholic fatty liver disease 下载免费PDF全文
4.
Marion Tardieu Najat Salameh Line Souris David Rousseau Laurène Jourdain Hanadi Skeif François Prévot Ludovic de Rochefort Denis Ducreux Bruno Louis Philippe Garteiser Ralph Sinkus Luc Darrasse Marie Poirier-Quinot Xavier Maître 《NMR in biomedicine》2022,35(7):e4701
Magnetic resonance elastography aims to non-invasively and remotely characterize the mechanical properties of living tissues. To quantitatively and regionally map the shear viscoelastic moduli in vivo, the technique must achieve proper mechanical excitation throughout the targeted tissues. Although it is straightforward, ante manibus, in close organs such as the liver or the breast, which practitioners clinically palpate already, it is somewhat fortunately highly challenging to trick the natural protective barriers of remote organs such as the brain. So far, mechanical waves have been induced in the latter by shaking the surrounding cranial bones. Here, the skull was circumvented by guiding pressure waves inside the subject's buccal cavity so mechanical waves could propagate from within through the brainstem up to the brain. Repeatable, reproducible and robust displacement fields were recorded in phantoms and in vivo by magnetic resonance elastography with guided pressure waves such that quantitative mechanical outcomes were extracted in the human brain. 相似文献
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《中国现代医生》2020,58(2):135-138+封三
目的探讨实时剪切波弹性成像在评估拉米夫定治疗乙肝纤维化临床疗效中的作用。方法选取2017年1月~2018年1月我院收治的80例乙肝纤维化患者,根据随机数字法分为对照组和观察组,每组40例。对照组采用常规治疗,观察组在对照组的基础上给予拉米夫定进行治疗,治疗6个月。比较两组治疗前后肝功能、肝纤维化指标,利用实时剪切波弹性成像评估两组治疗前后肝脏弹性模量值及肝穿刺活检情况,并进行比较。结果两组治疗后AST、ALT、TBIL水平均明显低于治疗前,差异有统计学意义(P0.05);观察组治疗后AST、ALT、TBIL水平均明显低于对照组,差异有统计学意义(P0.05);两组治疗后HA、LN、PⅢPN-P、CL-Ⅳ水平及杨氏弹性模量值均显著低于治疗前,差异有统计学意义(P0.05);观察组治疗后HA、LN、PⅢPN-P、CL-Ⅳ水平及杨氏弹性模量值均显著低于对照组,差异有统计学意义(P0.05);与治疗前相比,两组治疗后肝穿刺活检结果均有好转,尤其是汇管区、肝小叶内炎症及肝纤维化改善明显。结论实时剪切波弹性成像作为肝脏硬度定量检测的无创性技术,可用于拉米夫定治疗乙肝纤维化临床疗效评估的重要方法。 相似文献
7.
Sigita Gelman rius Sakalauskas Romanas Zykus rius Pranculis Rytis Jurkonis Irma Kuliavienė Arūnas Lukoševičius Limas Kupčinskas Juozas Kupčinskas 《World journal of gastroenterology : WJG》2020,26(38):5836-5848
BACKGROUND Degree of portal hypertension(PH) is the most important prognostic factor for the decompensation of liver cirrhosis and death, therefore adequate care for patients with liver cirrhosis requires timely detection and evaluation of the presence of clinically significant PH(CSPH) and severe PH(SPH). As the most accurate method for the assessment of PH is an invasive direct measurement of hepatic venous pressure gradient(HVPG), the search for non-invasive methods to diagnose these conditions is actively ongoing.AIM To evaluate the feasibility of parameters of endogenously induced displacements and strain of liver to assess degree of PH.METHODS Of 36 patients with liver cirrhosis and measured HVPG were included in the casecontrol study. Endogenous motion of the liver was characterized by derived parameters of region average tissue displacement signal(dantero, dretro, d RMS) and results of endogenous tissue strain imaging using specific radiofrequency signal processing algorithm. Average endogenous strain μ and standard deviation σ of strain were assessed in the regions of interest(ROI)(1 cm × 1 cm and 2 cm × 2 cm in size) and different frequency subbands of endogenous motion(0-10 Hz and 10-20 Hz).RESULTS Four parameters showed statistically significant(P 0.05) correlation with HVPG measurement. The strongest correlation was obtained for the standard deviation of strain(estimated at 0-10 Hz and 2 cm × 2 cm ROI size). Three parameters showed statistically significant differences between patient groups with CSPH, but only dretro showed significant results in SPH analysis. According to ROC analysis area under the curve(AUC) of the σROI[0…10 Hz, 2 cm × 2 cm] parameter reached 0.71(P = 0.036) for the diagnosis of CSPH; with a cut-off value of 1.28 μm/cm providing 73% sensitivity and 70% specificity. AUC for the diagnosis of CSPH for μROI[0…10 Hz, 1 cm × 1 cm] was 0.78(P = 0.0024); with a cut-off value of 3.92 μm/cm providing 73% sensitivity and 80% specificity. Dretro parameter had an AUC of 0.86(P = 0.0001) for the diagnosis of CSPH and 0.84(P = 0.0001) for the diagnosis of SPH. A cut-off value of-132.34 μm yielded 100% sensitivity for both conditions, whereas specificity was 80% and 72% for CSPH and SPH respectively.CONCLUSION The parameters of endogenously induced displacements and strain of the liver correlated with HVPG and might be used for non-invasive diagnosis of PH. 相似文献
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B C Goss K P McGee E C Ehman A Manduca R L Ehman 《Magnetic resonance in medicine》2006,56(5):1060-1066
Magnetic resonance elastography (MRE) is a phase-contrast technique that can spatially map shear stiffness within tissue-like materials. To date, however, MRE of the lung has been too technically challenging-primarily because of signal-to-noise ratio (SNR) limitations and phase instability. We describe an approach in which shear wave propagation is not encoded into the phase of the MR signal of a material, but rather from the signal arising from a polarized noble gas encapsulated within. To determine the feasibility of the approach, three experiments were performed. First, to establish whether shear wave propagation within lung parenchyma can be visualized with phase-contrast MR techniques, MRE was performed on excised porcine lungs inflated with room air. Second, a phantom consisting of open-cell foam filled with thermally polarized (3)He gas was imaged with MRE to determine whether shear wave propagation can be encoded by the gas. Third, preliminary evidence of the feasibility of MRE in vivo was obtained by using a longitudinal driver on the chest of a normal volunteer to generate shear waves in the lung. The results suggest that MRE in combination with hyperpolarized noble gases is potentially useful for noninvasively assessing the regional elastic properties of lung parenchyma, and merits further investigation. 相似文献
10.
The gold-standard method for diagnosing arteriogenic erectile dysfunction (AED) is the penile Doppler ultrasonography. We proposed a novel method for predicting AED using ultrasonic shear wave elastography (SWE) considering that the former was invasive and variable. A total of 98 male patients were enrolled in our study, referred for ED between December 2018 and October 2020. For comparison, we also included 42 volunteers from the Healthy Physical Examination Center of our hospital. The Penile Doppler Ultrasonography (PDU) and SWE were performed for all patients with the intracavernosal injection (ICI). We named three groups as AED group, nonvascular ED group and healthy controls group. No statistically significant differences were found among the three groups in terms of demographic and clinical characteristics. There were no significant differences in IIEF-5 between AED and nonvascular ED. A significant (r = 0.642, p < 0.0001) positive correlation between flaccid and erectile SWE was observed. With a cut-off value of 13.45 KPa, the area under curve, specificity, and sensitivity of the SWE values under the flaccid state in distinguishing AED from healthy subjects were 0.867, 0.786 and 0.896 respectively. The SWE value in the flaccid state can distinguish the AED from healthy subjects. 相似文献