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PurposeTo evaluate the effectiveness and safety of fluoroscopy-guided percutaneous high ligation (FPHL) combined with fluoroscopy-guided foam sclerotherapy (FGFS) to treat varicose veins of the great saphenous veins (GSVs).Materials and MethodsThis was a retrospective study of 113 patients (mean age, 62.1 ± 10.8 years; 60 men) with varicose veins of the GSVs (133 limbs) that were treated with FPHL combined with FGFS between April 1 and October 31, 2019. Demographic and clinical data were collected from these patients before the FPHL procedure, after which FGFS was performed. The preterminal GSV was ligated percutaneously by a percutaneously-positioned polypropylene ligature under fluoroscopic guidance. The outcome of ligation was confirmed by venography. Then, foam sclerotherapy was performed under fluoroscopy. At 1-year follow-up, GSV occlusion was evaluated by ultrasound. The venous clinical severity scores (VCSSs) were compared between the preoperative and 1-year follow-up periods.ResultsThe technical success rate was 100% (133 limbs). Complete 12-month follow-up was available for 112 limbs (84.2%) and 103 of these limbs (92.0%) remained occluded during this period. The VCSS improved from 4.71 ± 2.15 to 0.74 ± 0.60 (V = 6328, P < .001). During follow-up, there were 16 limbs with thrombophlebitis and 38 limbs with saphenous junction pain; these events were alleviated within 2 weeks of the procedure. There was no deep venous thrombosis or other severe adverse events.ConclusionsFPHL combined with FGFS to treat varicose veins in the GSVs achieved an occlusion rate of 92% and improved the clinical symptoms within 1 year; this minimally-invasive procedure was safe and effective.  相似文献   
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PurposeTo create a nonsurgical animal model of osteoarthritis (OA) to evaluate the effects of embolotherapy during geniculate artery embolization (GAE).Materials and MethodsFluoroscopy-guided injections of 700 mg of sodium monoiodoacetate were performed into the left stifle in 6 rams. Kinematic data were collected before and after induction. At 10 weeks after induction, Subjects 1 and 4–6 underwent magnetic resonance (MR) imaging with dynamic contrast enhancement (DCE) and Subjects 1, 3, and 4–6 underwent angiography with angiographic scoring to identify regions with greatest disease severity for superselective embolization (75–250-μm microspheres). Target vessel size was measured. At 24 weeks after angiography, DCE-MR imaging, angiography, and euthanasia were performed, and bilateral stifles were harvested. Medial/lateral tibial and femoral condylar, patellar, and synovial samples were cut, preserved, decalcified, and scored using the Osteoarthritis Research Society International criteria. The stifle and synovium Whole-Organ Magnetic Resonance Imaging Score and Multicenter Osteoarthritis Study score were determined. The volume transfer constant (Ktrans) and extracellular volume fraction (ve) were calculated from DCE-MR imaging along the lateral synovial regions of interest.ResultsThe mean gross and microscopic pathological scores were elevated at 38 and 61, respectively. Mean synovitis score was elevated at 9.2. Mean pre-embolization and postembolization angiographic scores were 5 and 3.8, respectively. Mean superior, transverse, and inferior geniculate artery diameters were 3.1 mm ± 1.21, 2.0 mm ± 0.50, and 1.6 mm ± 0.41 mm, respectively. Mean pre-embolization and postembolization cartilage and synovitis scores were elevated at 35.13 and 73.3 and 5.5 and 9.2, respectively. The Ktrans/ve values of Subjects 4, 5, and 6 were elevated at 0.049/0.38, 0.074/0.53, and 0.065/0.51, respectively. Altered gait of the hind limb was observed in all subjects after induction, with reduced joint mobility. No skin necrosis or osteonecrosis was observed.ConclusionsA nonsurgical ovine animal knee OA model was created, which allowed the collection of angiographic, histopathological, MR imaging, and kinematic data to study the effects of GAE.  相似文献   
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目的利用多体素氢质子磁共振波谱成像(hydrogen proton magnetic resonance spectroscopy,1H-MRS)探讨慢性高原病(chronic mountain sickness,CMS)长期缺氧状态下脑部代谢物的特点,并比较各代谢物与血液指标之间的相关性。材料与方法前瞻性纳入青海大学附属医院经临床确诊为CMS的17例男性患者作为实验组,年龄(53.29±9.03)岁,居住海拔(3989.12±937.45)m,血红蛋白(hemoglobin,HGB)(224.35±11.81)g/mL,并招募与实验组年龄及居住海拔相匹配的18名健康男性志愿者作为对照组,年龄(48.61±8.76)岁,居住海拔(3674.94±634.27)m,HGB(156.67±9.46)g/mL。采用Siemens Prisma 3.0 T MR扫描仪20通道头颅线圈对所有受试者行常规头颅MRI及多体素;H-MRS检查,通过Syngo.via后处理软件获得;H-MRS图,ROI选取双侧额叶及海马区,并获得相应脑区N-乙酰天门冬氨酸/肌酸(NAA/Cr)、胆碱/肌酸CHo/Cr、乙酰天门冬氨酸/胆碱(NAA/CHo)、乳酸/肌酸(Lac/Cr)的比值。结合独立样本t检验及非参数曼-惠特尼U检验以比较两组间代谢物相对浓度差异,然后将CMS组双侧额叶及海马区各代谢物比值与血液生化指标作相关性分析。结果(1)两组受试者年龄、长期居住海拔差异均无统计学意义(P>0.05),而与对照组相比,CMS组HGB、红细胞计数(red blood cell count,RBC)、血细胞比容(hematocrit,HCT)增高,血小板(blood platelet,简称PLT)减低,差异均有统计学意义(P<0.01);(2)与对照组相比,CMS组双侧额叶及海马区NAA/Cr及NAA/CHo均减低(P<0.05),Lac/Cr增高(P<0.05),差异均具有统计学意义;(3)与对照组相比,CMS组双侧额叶及双侧海马区CHo/Cr均增高(P>0.05),差异无统计学意义;(4)CMS组右侧额叶及左侧海马CHo/Cr与RBC明显正相关,左侧额叶CHo/Cr与HCT低度正相关,右侧额叶及左侧海马Lac/Cr与HCT低度正相关。结论CMS长期缺氧状态下脑组织局部代谢物改变,神经元受损,无氧代谢增加,且这些代谢物的改变与血液指标呈一定的相关性,可为临床后续进一步预防或干预CMS患者脑损害提供影像学证据及监测指标。  相似文献   
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PurposeTo assess the safety and tolerability of a vandetanib-eluting radiopaque embolic (BTG-002814) for transarterial chemoembolization (TACE) in patients with resectable liver malignancies.Materials and MethodsThe VEROnA clinical trial was a first-in-human, phase 0, single-arm, window-of-opportunity study. Eligible patients were aged ≥18 years and had resectable hepatocellular carcinoma (HCC) (Child-Pugh A) or metastatic colorectal cancer (mCRC). Patients received 1 mL of BTG-002814 transarterially (containing 100 mg of vandetanib) 7–21 days prior to surgery. The primary objectives were to establish the safety and tolerability of BTG-002814 and determine the concentrations of vandetanib and the N-desmethyl vandetanib metabolite in the plasma and resected liver after treatment. Biomarker studies included circulating proangiogenic factors, perfusion computed tomography, and dynamic contrast-enhanced magnetic resonance imaging.ResultsEight patients were enrolled: 2 with HCC and 6 with mCRC. There was 1 grade 3 adverse event (AE) before surgery and 18 after surgery; 6 AEs were deemed to be related to BTG-002814. Surgical resection was not delayed. Vandetanib was present in the plasma of all patients 12 days after treatment, with a mean maximum concentration of 24.3 ng/mL (standard deviation ± 13.94 ng/mL), and in resected liver tissue up to 32 days after treatment (441–404,000 ng/g). The median percentage of tumor necrosis was 92.5% (range, 5%–100%). There were no significant changes in perfusion imaging parameters after TACE.ConclusionsBTG-002814 has an acceptable safety profile in patients before surgery. The presence of vandetanib in the tumor specimens up to 32 days after treatment suggests sustained anticancer activity, while the low vandetanib levels in the plasma suggest minimal release into the systemic circulation. Further evaluation of this TACE combination is warranted in dose-finding and efficacy studies.  相似文献   
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ObjectiveThe purpose of this study was to determine whether chiropractic clinicians modulate spinal manipulation (SM) thrust characteristics based on visual perception of simulated human silhouette attributes.MethodsWe performed a cross-sectional within-participant design with 8 experienced chiropractors. During each trial, participants observed a human-shaped life-sized silhouette of a mock patient and delivered an SM thrust on a low-fidelity thoracic spine model based on their visual perception. Silhouettes varied on the following 3 factors: apparent sex (male or female silhouette), height (short, average, tall), and body mass index (BMI) (underweight, healthy, obese). Each combination was presented 6 times for a total of 108 trials in random order. Outcome measures included peak thrust force, thrust duration, peak preload force, peak acceleration, time to peak acceleration, and rate of force application. A 3-way repeated measures analysis of variance model was used to for each variable, followed by Tukey's honestly significant difference on significant interactions.ResultsPeak thrust force was reduced when apparent sex of the presented silhouette was female (F1,7 = 5.70, P = .048). Thrust duration was largely invariant, except that a BMI by height interaction revealed a longer duration occurred for healthy tall participants than healthy short participants (F4,28 = 4.34, P = .007). Compared to an image depicting obese BMI, an image appearing underweight lead to reduced peak acceleration (F2,5 = 6.756, P = .009). Clinician time to peak acceleration was reduced in short compared to tall silhouettes (t7 = 2.20, P = .032).ConclusionVisual perception of simulated human silhouette attributes, including apparent sex, height, and BMI, influenced SM dose characteristics through both kinetic and kinematic measures. The results suggest that visual information from mock patients affects the decision-making of chiropractic clinicians delivering SM thrusts.  相似文献   
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