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1.
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
2.
PNPLA3 gene polymorphism and response to lifestyle modification in patients with nonalcoholic fatty liver disease
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3.
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
6.
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
7.
Shinichiro Uchiyama Takao Hoshino Leila Sissani Monteiro Tavares Linsay Kenji Kamiyama Taizen Nakase Kazuo Kitagawa Kazuo Minematsu Kenichi Todo Yasushi Okada Jyoji Nakagawara Ken Nagata Hiroshi Yamagami Takenori Yamaguchi Pierre Amarenco 《Journal of stroke and cerebrovascular diseases》2019,28(8):2232-2241
BackgroundTIAregistry.org is an international cohort of patients with transient ischemic attack (TIA) or minor stroke within 7 days before enrollment in the registry. Main analyses of 1-year follow-up data have been reported.5 We conducted subanalysis on the baseline and 1-year follow-up data of Japanese patients.MethodsThe patients were classified into 2 groups based on Japanese ethnicity, Japanese (345) and non-Japanese (3238), and their baseline data and 1-year event rates were compared. We also determined risk factors and predictors of 1-year stroke.ResultsCurrent smoking, regular alcohol drinking, intracranial arterial stenosis, and small vessel occlusion; and hypertension, dyslipidemia, coronary artery disease, and extracranial arterial stenosis were more and less common among Japanese patients, respectively. Stroke risk was higher and TIA risk was lower at 1-year follow-up among Japanese patients. The baseline risk factors for recurrent stroke were diabetes, alcohol drinking, and large artery atherosclerosis. Independent predictors of 1-year stroke risk were prior congestive heart failure and alcohol consumption.ConclusionsThe two populations of patients featured differences in risk factors, stroke subtypes, and outcome events. Predictors of recurrent stroke among Japanese patients included congestive heart failure and regular alcohol drinking. Strategies to attenuate residual risk of stroke aside from adherence to current guidelines should take our Japanese-patient specific findings into account. 相似文献
8.
Allan Young 《L'évolution Psychiatrique》2002,67(4):630
Conceived of during the Vietnam war, the hypothesis that the perpetrators of atrocities could subsequently develop psychiatric disorders identical to those of their victims led to the emergence of a specific category: the self-traumatized perpetrator. While the United States was discovering that its soldiers had been involved in appallingly barbaric acts, psychiatry through the DSM-III post-traumatic stress disorder provided a more conciliatory response to the behavior of those veterans by shifting the political issue into the sphere of clinical debate. The author examines the origin, development and the subsequent exhaustion of this category from a strictly anthropological point of view. In this study, the category of self-traumatized perpetrator has been constructed on the basis of psychological knowledge and of various influencing external factors. In this sense, it can be viewed as transient category as far as psychiatric nosology is concerned, and is closely dependent on the outcome of the political and social issues that favored its emergence, and destined to disappear with them. In adopting the term coined by Ian Hacking, the author shows that the disorder observed in the case of the self-traumatized perpetrator is above all a “transient mental illness” 相似文献
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Kazumichi Yamada Satoshi Goto Taro Oyama Makoto Yoshikawa Shinji Nagahiro Yukitaka Ushio 《Acta neuropathologica》1995,89(2):172-177
The present study concerns the vulnerability of striatal interneurons immunopositive for the Ca2+-binding protein calretinin to ischemic neuronal injury. An immunohistochemical study was carried out on the striata of rats which had undergone transient middle cerebral artery occlusion. Two weeks after the ischemia, there was a marked reduction in the number of calretinin-positive neurons in the ipsilateral ischemic lesion, although the striatal interneurons positive for parvalbumin, which are a neuronal population distinct from the calretinin-immunoreactive cells in the striatum, were spared in the insulted areas. The present data indicate that the striatal calretinin-positive neurons are less resistant to transient ischemia, suggesting that there may exist vulnerability differences among the striatal interneurons in ischemia-induced neuronal injury. 相似文献