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11.
Hui-Ju Ch’ang 《World journal of hepatology》2015,7(16):2029-2040
The success of sorafenib in prolonging survival of patients with hepatocellular carcinoma (HCC) makes therapeutic inhibition of angiogenesis a component of treatment for HCC. To enhance therapeutic efficacy, overcome drug resistance and reduce toxicity, combination of antiangiogenic agents with chemotherapy, radiotherapy or other targeted agents were evaluated. Nevertheless, the use of antiangiogenic therapy remains suboptimal regarding dosage, schedule and duration of therapy. The issue is further complicated by combination antiangiogenesis to other cytotoxic or biologic agents. There is no way to determine which patients are most likely respond to a given form of antiangiogenic therapy. Activation of alternative pathways associated with disease progression in patients undergoing antiangiogenic therapy has also been recognized. There is increasing importance in identifying, validating and standardizing potential response biomarkers for antiangiogenesis therapy for HCC patients. In this review, biomarkers for antiangiogenesis therapy including systemic, circulating, tissue and imaging ones are summarized. The strength and deficit of circulating and imaging biomarkers were further demonstrated by a series of studies in HCC patients receiving radiotherapy with or without thalidomide. 相似文献
12.
《Diagnostic and interventional imaging》2020,101(12):821-830
PurposeTo compare morphological imaging features and CT texture histogram parameters between grade 3 pancreatic neuroendocrine tumors (G3-NET) and neuroendocrine carcinomas (NEC).Materials and methodsPatients with pathologically proven G3-NET and NEC, according to the 2017 World Health Organization classification who had CT and MRI examinations between 2006-2017 were retrospectively included. CT and MRI examinations were reviewed by two radiologists in consensus and analyzed with respect to tumor size, enhancement patterns, hemorrhagic content, liver metastases and lymphadenopathies. Texture histogram analysis of tumors was performed on arterial and portal phase CT images. images. Morphological imaging features and CT texture histogram parameters of G3-NETs and NECs were compared.ResultsThirty-seven patients (21 men, 16 women; mean age, 56 ± 13 [SD] years [range: 28-82 years]) with 37 tumors (mean diameter, 60 ± 46 [SD] mm) were included (CT available for all, MRI for 16/37, 43%). Twenty-three patients (23/37; 62%) had NEC and 14 patients (14/37; 38%) had G3-NET. NECs were larger than G3-NETs (mean, 70 ± 51 [SD] mm [range: 18 - 196 mm] vs. 42 ± 24 [SD] mm [range: 8 - 94 mm], respectively; P = 0.039), with more tumor necrosis (75% vs. 33%, respectively; P = 0.030) and lower attenuation on precontrast (30 ± 4 [SD] HU [range: 25-39 HU] vs. 37 ± 6 [SD] [range: 25-45 HU], respectively; P = 0.002) and on portal venous phase CT images (75 ± 18 [SD] HU [range: 43 - 108 HU] vs. 92 ± 19 [SD] HU [range: 46 - 117 HU], respectively; P = 0.014). Hemorrhagic content on MRI was only observed in NEC (P = 0.007). The mean ADC value was lower in NEC ([1.1 ± 0.1 (SD)] × 10−3 mm2/s [range: (0.91 - 1.3) × 10−3 mm2/s] vs. [1.4 ± 0.2 (SD)] × 10−3 mm2/s [range: (1.1 - 1.6) × 10−3 mm2/s]; P = 0.005). CT histogram analysis showed that NEC were more heterogeneous on portal venous phase images (Entropy-0: 4.7 ± 0.2 [SD] [range: 4.2-5.1] vs. 4.5 ± 0.4 [SD] [range: 3.7-4.9]; P = 0.023).ConclusionPancreatic NECs are larger, more frequently hypoattenuating and more heterogeneous with hemorrhagic content than G3-NET on CT and MRI. 相似文献
13.
《Diagnostic and interventional imaging》2020,101(9):555-564
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%. 相似文献
14.
经济社会的快速发展,提升了人们的生活水平人们对医疗事业的发展提出了更高的要求,我国也加大了对医疗事业的建设与发展。尤其是所使用的相关设备与仪器。其中,医用B超就是最主要的医疗设备,能够通过设备的检查,对人体的身体情况以数据的形式展现,直接能够了解到人体的健康情况,提升医疗事业的技术水平,同时,也为医疗工作这提供了方便快捷的工作方式。但是,医用B超设备在使用的过程中,会受到一些因素的影响,使其发生故障,会对各项工作造成不同程度的影响。因此,需要对其加强管理,能够及时地发现故障问题,采取科学的措施解决,确保医疗事业的稳定发展。 相似文献
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17.
《The Journal of emergency medicine》2020,58(6):e237-e241
BackgroundThe anatomic course of the phrenic nerve runs in the fascia covering the anterior scalene muscle. Interscalene blocks are commonly performed by an anesthesiologist for shoulder surgery, such as a rotator cuff repair, total shoulder replacement, humeral fracture, or other arm surgery. Phrenic nerve palsy or paralysis is a known complication from interscalene block and is covered in multiple case reports and series in both Anesthesia and Neurosurgical literature, but only one case report in the Emergency Medicine literature.Case ReportThis case involves a 57-year-old man who had an uncomplicated arthroscopic rotator cuff repair with placement of interscalene block under care of anesthesia. He was discharged with a pain pump in place and then subsequently presented to the Emergency Department (ED) later that same day for evaluation of dyspnea. Using point-of-care ultrasound, his right diaphragm did not appear to be moving. Chest x-ray study revealed an elevated right hemidiaphragm. He was diagnosed with iatrogenic right phrenic nerve paralysis from interscalene block.Why Should an Emergency Physician Be Aware of This?Emergent diagnosis of phrenic nerve paralysis in the ED is complicated by a distressed patient and need for quick intervention. Most formal tests for this diagnosis are not immediately available to emergency physicians. Ultrasound is a rapid and reproducible, noninvasive resource with high sensitivity and specificity, making it an ideal imaging modality for the emergent evaluation of possible phrenic nerve palsy or paralysis. 相似文献
18.
Jamaal L. Benjamin MD PhD Rebecca Dennis DO Stacy White Jr MD David Munson MD Sudha A. Anupindi MD Maciej Piskunowicz MD Kassa Darge MD PhD Ami Gokli MD Misun Hwang MD 《Journal of ultrasound in medicine》2020,39(5):1031-1036
Bowel diseases of prematurity, including necrotizing enterocolitis, are dreaded ailments of neonates. Early diagnosis is difficult, with clinical and radiographic findings often inconclusive. We present a novel use of contrast-enhanced ultrasound in detection of pediatric bowel disease. Early identification of compromised blood flow or an at-risk bowel can be quantitatively detected and monitored. This ability has implications for guidance of emerging therapies, allowing targeting of inflammation. These findings represent an advancement in detection of bowel disease in neonates. 相似文献
19.
《The Journal of emergency medicine》2020,58(2):e47-e50
BackgroundBupropion overdose is a commonly encountered presentation in the emergency department (ED). While the majority of cases resolve with supportive care, serious adverse effects, including seizures, cardiogenic shock, and death, can occur. Intravenous lipid emulsion (ILE) therapy has been utilized for a multitude of poisonings with varying levels of success. Although a number of cases suggest the value of ILE therapy in cases of bupropion overdose, more recent data propose that its role may be overstated.Case ReportA young woman presented to the ED with altered mental status complicated by seizure after bupropion overdose. She subsequently developed cardiogenic shock requiring vasopressor support. Bedside echocardiogram revealed a decreased left ventricular ejection fraction (LVEF). She received ILE therapy with significant improvement in both hemodynamic status and LVEF by bedside ultrasound.Why Should an Emergency Physician Be Aware of This?Although the majority of patients presenting with bupropion overdose improve with supportive care, life-threatening sequelae are possible. ILE therapy has shown promise in a variety of different overdose situations, although the evidence in cases of bupropion poisoning has been varied, and it has traditionally been utilized as a last-line rescue modality. Based on hemodynamic parameters and bedside ultrasound, this case suggests that early initiation of ILE therapy should be considered in these cases, as the potential benefits likely outweigh the theoretical risks. 相似文献
20.
Maxime Lafond Shin Yoshizawa Shin‐ichiro Umemura 《Journal of ultrasound in medicine》2019,38(3):567-580
Sonodynamic therapy (SDT) consists of the synergetic interaction between ultrasound and a chemical agent. In SDT, the cytotoxicity is triggered by ultrasonic stimuli, notably through cavitation. The unique features of SDT are relevant in the clinical context more than ever: the need for efficacy, accuracy, and safety while being noninvasive and preserving the patient's quality of life. However, despite the promising results of this technique, only a few clinical reports describe the use of SDT. The objective of this article is to provide an extensive overview of the clinical and preclinical research conducted in vivo on SDT, to identify the limitations, and to detail the developed strategies to overcome them. 相似文献