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1.
ObjectivesThe aim of this study was to test whether optical coherence tomographic (OCT) guidance would provide additional useful information beyond that obtained by angiography and lead to a shift in reperfusion strategy and improved clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI) with early infarct artery patency.BackgroundAngiography is limited in assessing the underlying pathophysiological mechanisms of the culprit lesion.MethodsEROSION III (Optical Coherence Tomography–Guided Reperfusion in ST-Segment Elevation Myocardial Infarction With Early Infarct Artery Patency) is an open-label, prospective, multicenter, randomized, controlled study approved by the ethics committees of participating centers. Patients with STEMI who had angiographic diameter stenosis ≤ 70% and TIMI (Thrombolysis In Myocardial Infarction) flow grade 3 at presentation or after antegrade blood flow restoration were recruited and randomized to either OCT guidance or angiographic guidance. The primary efficacy endpoint was the rate of stent implantation.ResultsAmong 246 randomized patients, 226 (91.9%) constituted the per protocol set (112 with OCT guidance and 114 with angiographic guidance). The median diameter stenosis was 54.0% (IQR: 48.0%-61.0%) in the OCT guidance group and 53.5% (IQR: 43.8%-64.0%) in the angiographic guidance group (P = 0.57) before randomization. Stent implantation was performed in 49 of 112 patients (43.8%) in the OCT group and 67 of 114 patients (58.8%) in the angiographic group (P = 0.024), demonstrating a 15% reduction in stent implantation with OCT guidance. In patients treated with stent implantation, OCT guidance was associated with a favorable result with lower residual angiographic diameter stenosis (8.7% ± 3.7% vs 11.8% ± 4.6% in the angiographic guidance group; P < 0.001). Two patients (1 cardiac death, 1 stable angina) met the primary safety endpoint in the OCT guidance group, as did 3 patients (3 cardiac deaths) in the angiographic guidance group (1.8% vs 2.6%; P = 0.67). Reinfarction was not observed in either group. At 1 year, the rates of predefined cardiocerebrovascular events were comparable between the groups (11.6% after OCT guidance vs 9.6% after angiographic guidance; P = 0.66).ConclusionsIn patients with STEMI with early infarct artery patency, OCT guidance compared with angiographic guidance of reperfusion was associated with less stent implantation during primary percutaneous coronary intervention. These favorable results indicate the value of OCT imaging in optimizing the reperfusion strategy of patients with STEMI. (EROSION III: OCT- vs Angio-Based Reperfusion Strategy for STEMI; NCT03571269)  相似文献   
2.
BackgroundIschemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat.MethodsRat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed.ResultsPre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators.ConclusionOur result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction.  相似文献   
3.
《Pancreatology》2022,22(6):698-705
BackgroundThe functional and morphological recovery following an episode of acute pancreatitis (AP) in children still remains ill understood as research exploring this is limited. We aimed to characterize the morphological and functional changes in pancreas following AP and ARP (acute recurrent pancreatitis) in children.MethodsChildren with AP were followed prospectively and assessed at two time points at least 3 months apart, with the first assessment at least 3 months after the AP episode. Exocrine and endocrine functions were measured using fecal elastase and fasting blood sugar/HbA1c levels respectively. Morphological assessment was done using endoscopic ultrasound (EUS) and magnetic resonance imaging and cholangiopancreatography (MRI/MRCP).ResultsSeventy-three children (boys:59%; mean age:8.4 ± 3.2years) were studied and 21 of them (29%) progressed to ARP. Altered glucose homeostasis was seen in 19 (26%) at first and 16 (22%) at second assessment and it was significantly more in ARP group than the AP group at first (42.8%vs19.2%; p = 0.03) as well as second assessment (38.1%vs15.3%; p = 0.03). Twenty-one children (28.7%) at first and 24 (32.8%) at second assessment developed biochemical exocrine pancreatic insufficiency. EUS detected indeterminate and suggestive changes of chronic pancreatitis in 21% at first (n = 38) and 27.6% at second assessment (n = 58). On MRCP, main pancreatic duct and side branch dilatation were seen in 15 (20.5%) and 2 (2.7%) children respectively.ConclusionsMore than one-quarter of children have evidence of altered glucose homeostasis and biochemical exocrine pancreatic insufficiency following an episode of AP. Similarly, morphological features of chronicity seen in some of the children suggest that a fraction of subjects may develop chronic pancreatitis on longer follow-up.  相似文献   
4.
Semantic instance segmentation is crucial for many medical image analysis applications, including computational pathology and automated radiation therapy. Existing methods for this task can be roughly classified into two categories: (1) proposal-based methods and (2) proposal-free methods. However, in medical images, the irregular shape-variations and crowding instances (e.g., nuclei and cells) make it hard for the proposal-based methods to achieve robust instance localization. On the other hand, ambiguous boundaries caused by the low-contrast nature of medical images (e.g., CT images) challenge the accuracy of the proposal-free methods. To tackle these issues, we propose a proposal-free segmentation network with discriminative deep supervision (DDS), which at the same time allows us to gain the power of the proposal-based method. The DDS module is interleaved with a carefully designed proposal-free segmentation backbone in our network. Consequently, the features learned by the backbone network become more sensitive to instance localization. Also, with the proposed DDS module, robust pixel-wise instance-level cues (especially structural information) are introduced for semantic segmentation. Extensive experiments on three datasets, i.e., a nuclei dataset, a pelvic CT image dataset, and a synthetic dataset, demonstrate the superior performance of the proposed algorithm compared to the previous works.  相似文献   
5.
患者女,58岁,无明显诱因出现右侧腰骶部及右下肢疼痛麻木3年余,伴右下肢上抬无力和大小便感觉异常,近半年来症状加重;既往无腰部外伤史及其他疾病史。查体:右下肢肌力4级,实体觉、图形觉、两点分辨异常,巴宾斯基征及霍夫曼征阴性。实验室检查未见明显异常。腰椎CT:L3~L4椎体层面椎管内不规则稍高密度影,内见斑点状钙化(图1A),邻近骨质无破坏。  相似文献   
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7.
目的 观察双能量CT (DECT)定量参数术前预测实性肺腺癌气道播散(STAS)状态的价值。方法 回顾性分析52例经手术病理确诊实性肺腺癌患者的DECT及病理学资料,评估其STAS状态(阳性或阴性);对比STAS阳性、阴性实性肺腺癌CT表现(最大径、周围不透明影、空气支气管征、胸膜凹陷征)及DECT定量参数的差异。针对差异有统计学意义的DECT定量参数绘制受试者工作特征(ROC)曲线,计算曲线下面积(AUC),评估DECT定量参数单独及联合预测实性肺腺癌STAS的效能,并以二元logistic回归分析筛选实性肺腺癌STAS的独立预测因子。结果 52例中,25例STAS阳性,27例STAS阴性,其间病灶CT表现差异均无统计学意义(P均>0.05),DECT定量参数中的动脉期碘浓度(ICA)、动脉期标准化碘浓度(NICA)及静脉期碘浓度(ICV)差异均有统计学意义(P均<0.05)。ICA、NICA及ICV预测实性肺腺癌STAS的AUC为0.82、0.83及0.73;ICA和NICA均为实性肺腺癌STAS的独立预测因子,其联合AUC为0.89。结论 DECT定量参数可有效预测实性肺腺癌STAS。  相似文献   
8.
目的:应用扫频光学相干断层扫描血管成像(SS-OCTA)对比研究白内障术中不同眼内压患者手术前后黄斑区血流的变化情况,为白内障个性化手术参数设计提供临床参考。

方法:前瞻性随机对照研究。收集2021-01/04于四川省人民医院住院行白内障手术的患者61例77眼,使用随机数字表分为A组(37眼)和B组(40眼),术中分别予以75、90cm灌注瓶瓶高,相当于55.5、66.6mmHg术中平均眼内压。所有患者除常规眼科检查外,术前、术后1、7、30d均行黄斑区SS-OCTA检查,观察黄斑区视网膜厚度及放射状毛细血管网(RPCP)层、浅层血管网(SVP)层、中层血管网(IVP)层、深层血管网(DVP)层灌注面积和血管密度。

结果:手术前后各时间点两组患者最佳矫正视力(BCVA)、眼压、黄斑中心凹无血管区(FAZ)面积、黄斑区视网膜厚度及各层灌注面积和血管密度均无组间差异性(均P>0.05),但均有时间差异性(均P<0.05),两组患者术后各时间点BCVA均较术前明显改善,眼压和FAZ面积均较术前下降(均P<0.05),黄斑区视网膜厚度及各层灌注面积和血流密度均较术前增加。

结论:白内障术后黄斑区视网膜厚度及各层血流密度和灌注面积均增加,FAZ面积下降,有助于促进术后视力的恢复,且术中选择55.5、66.6mmHg不同眼内压情况下,患者术后眼底血流改变情况无明显差异,故术中可以灵活选择眼内压,为患者提供个性化手术设计方案。  相似文献   

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10.
Diabetic macular ischaemia (DMI) is traditionally defined and graded based on the angiographic evidence of an enlarged and irregular foveal avascular zone. However, these anatomical changes are not surrogate markers for visual impairment. We postulate that there are vascular phenotypes of DMI based on the relative perfusion deficits of various retinal capillary plexuses and choriocapillaris. This review highlights several mechanistic pathways, including the role of hypoxia and the complex relation between neurons, glia, and microvasculature. The current animal models are reviewed, with shortcomings noted. Therefore, utilising the advancing technology of optical coherence tomography angiography (OCTA) to identify the reversible DMI phenotypes may be the key to successful therapeutic interventions for DMI. However, there is a need to standardise the nomenclature of OCTA perfusion status. Visual acuity is not an ideal endpoint for DMI clinical trials. New trial endpoints that represent disease progression need to be developed before irreversible vision loss in patients with DMI. Natural history studies are required to determine the course of each vascular and neuronal parameter to define the DMI phenotypes. These DMI phenotypes may also partly explain the development and recurrence of diabetic macular oedema. It is also currently unclear where and how DMI fits into the diabetic retinopathy severity scales, further highlighting the need to better define the progression of diabetic retinopathy and DMI based on both multimodal imaging and visual function. Finally, we discuss a complete set of proposed therapeutic pathways for DMI, including cell-based therapies that may provide restorative potential.  相似文献   
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