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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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Arterial spin labeling (ASL) imaging is a powerful magnetic resonance imaging technique that allows to quantitatively measure blood perfusion non-invasively, which has great potential for assessing tissue viability in various clinical settings. However, the clinical applications of ASL are currently limited by its low signal-to-noise ratio (SNR), limited spatial resolution, and long imaging time. In this work, we propose an unsupervised deep learning-based image denoising and reconstruction framework to improve the SNR and accelerate the imaging speed of high resolution ASL imaging. The unique feature of the proposed framework is that it does not require any prior training pairs but only the subject's own anatomical prior, such as T1-weighted images, as network input. The neural network was trained from scratch in the denoising or reconstruction process, with noisy images or sparely sampled k-space data as training labels. Performance of the proposed method was evaluated using in vivo experiment data obtained from 3 healthy subjects on a 3T MR scanner, using ASL images acquired with 44-min acquisition time as the ground truth. Both qualitative and quantitative analyses demonstrate the superior performance of the proposed txtc framework over the reference methods. In summary, our proposed unsupervised deep learning-based denoising and reconstruction framework can improve the image quality and accelerate the imaging speed of ASL imaging.  相似文献   
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Vascular injuries that occur during traffic accidents are a commonly neglected aspect that can add more detail to the framework of a case. In this study, we analysed a case series of 150 traffic accidents, 39 of which were marked by microscopically identifiable vascular lesions. The purpose was to identify the presence of carotid injuries in individuals who died due to traffic accidents and had nonpenetrating trauma of the neck. We focused on the discrepancies regarding the macroscopical aspect and the histology and demonstrated how histological analysis of the carotids in cases of trauma can reveal injuries that are attributable to the trauma itself. We conducted a histological analysis of the lesions to describe their distribution and type and investigate potential correlations. The study offers insight on how to examine road accidents that involve traumatic injury of the carotid arteries. Indeed the main task of the forensic pathologist in the case of death is to establish the existence of a causal relationship between the micro- or macroscopic alterations observed in the autopsy and the traumatic event that led to the death of the subject. Thus, further morphological elements were provided to the forensic practitioners that may reveal injuries attributable to the trauma itself and should be evaluated in cases of trauma in traffic accidents.  相似文献   
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BackgroundA comprehensive re-evaluation on the role of trans-arterial chemoembolization (TACE) in patients with intrahepatic cholangiocarcinoma.MethodsA thorough database searching was performed in PubMed, EMBASE, and the Cochrane Library. Eligible studies were restricted to comparative studies between TACE and non-TACE cohorts. RevMan5.3 software and Stata 13.0 software were used for statistical analyses. The primary endpoint of our study was long-term survival.ResultsA total of 11 studies with 2036 patients were finally identified. Pooled results revealed that patients receiving TACE had a significantly better overall survival (OS) versus those without TACE (P < 0.05). Subgroup analyses were performed according to different types of TACE. Prophylactic post-surgical TACE (PPTACE) was associated with a significantly better OS versus those without PPTACE (P < 0.05). Palliative TACE (PTACE) also achieved a significantly better OS compared with those with supportive treatment (ST) only (P < 0.00001). However, TACE had no impact on disease-free survival (P = 0.87) and was less effective than surgical resection (P = 0.003).ConclusionPPTACE has a remarkable impact on OS versus those with surgical resections only and should be regularly performed. Regarding patients with unresectable disease, apart from conventional ST, adjuvant PTACE is also recommended. Upcoming prospective randomized controlled trials are warranted for further validation.  相似文献   
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PurposeTo prospectively determine the rate of radial artery occlusion (RAO) in patients undergoing transradial access for intra-arterial interventions.Materials and MethodsSeventy-seven patients undergoing transradial access from August 2019 to March 2021 for 120 intra-arterial procedures (yttrium-90 mapping [n = 39] and radioembolization [n = 38], uterine artery embolization [n = 19], transarterial chemoembolization [n = 10], active bleed embolization [n = 8], angiomyolipoma embolization [n = 4], and other [n = 2]) were enrolled. The average patient age was 59 years ± 13.1 (range, 30–90 years), and 43 (55.8%) of the 77 patients were men. The patients underwent radial artery (RA) palpation, ultrasound evaluation, the Barbeau test, and the reverse Barbeau test prior to and following the intervention. Verapamil, nitroglycerin, and heparin were administered in a total of 114 (95%) of the 120 procedures prior to starting the procedure. The incidence of RAO and radial artery spasm (RAS) was calculated, and univariate logistic regression was performed to analyze the predictors of RAS.ResultsThe preprocedural RA diameter (3.0 mm ± 0.67) was not significantly different from the postprocedural RA diameter (3.0 mm ± 0.65, P = .904). The RAO rate was determined to be 0.8% (1/120), and this artery recanalized within 1 week. Due to the small number of occlusions, statistical analysis of predictors of RAO was not performed. The rate of RAS was 22.7% (27/119). None of the variables tested—including age, sex, RA diameter, initial versus repeat access, operator experience, and artery puncture technique—showed significant prediction for RAS. Patients were seen for follow-up after 111 (92.5%) of the 120 procedures.ConclusionsTransradial access resulted in a <1% rate of RAO.  相似文献   
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