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《Journal of vascular and interventional radiology : JVIR》2022,33(3):249-254.e1
An ovine iliac vein thrombosis model was devised to test a wall-contacting rotational thrombectomy device. Thrombosis was successfully induced in 9 sheep with an average clot length of 31 mm ± 12 and >60% vessel occlusion on angiography. The thrombus was subsequently removed, maintaining normal intraoperative pulmonary arterial pressure (5.9 mm Hg ± 3.6) and complete distal reperfusion after thrombectomy. Additionally, the sheep were without signs of vascular trauma or embolic complications on gross necropsy and histopathologic analysis. The findings from this study support the use of an ovine iliac deep vein thrombosis model for testing of a lower extremity thrombectomy device. 相似文献
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《Journal of vascular and interventional radiology : JVIR》2022,33(12):1531-1535
This study investigated the role of dual-energy computed tomography (CT) for lesion characterization in patients with peripheral arterial disease manifesting with chronic total occlusions (CTOs). Forty-one symptomatic patients with CTOs underwent dual-energy CT angiography before endovascular treatment. The lesions were subsequently analyzed in a dedicated workstation, and 2 indexes—dual-energy index (DEI) and effective Z (Zeff)—were calculated, ranging from 0.0027 to 0.321 and from 6.89 to 13.02, respectively. Statistical analysis showed a significant correlation between the DEI and Zeff values (P < .001). The interobserver intraclass correlation coefficient was 0.91 for the mean Zeff values and 0.86 for the mean DEI values. This technique could potentially provide useful information regarding the composition of a CTO. 相似文献
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Clinical observation of vitrectomy combined with endolaser photocoagulation at the edge of posterior scleral staphyloma for macular hole retinal detachment in high myopia 下载免费PDF全文
AIM: To observe the clinical effect of pars plana vitrectomy (PPV) and silicone oil filling surgery combined with intraoperative posterior scleral staphyloma (PS) marginal retinal photocoagulation in the treatment of high myopic macular hole retinal detachment (MHRD) with PS.
METHODS: This was a retrospective clinical study. From May 2017 to March 2020, 62 MHRD patients with PS (62 eyes) were enrolled in the study. Patients were divided into 23G PPV combined with PS marginal retina intraoperative photocoagulation group (combined group) and conventional surgery group (conventional group), with 31 eyes in each. Triamcinolone acetonide and indocyanine green were used to remove the epiretinal membrane and the posterior macular inner limiting membrane (ILM). In the combined group, 2 to 3 rows of retinal photocoagulation were performed on the edge of the PS. The patients were followed up for an average of 8.34±3.21mo. The first retinal reattachment rate, macular hole closure rate, Duration of silicone oil tamponade, best corrected visual acuity (BCVA) and average number of operations were observed and compared between the two groups.
RESULTS: The first retinal reattachment rates of the eyes in the combined group and the conventional group were 96.7% (29/31) and 67.7% (21/31), respectively (χ2=6.613, P=0.010). The macular hole closure rates in the combined group and the conventional group were 74.2% (23/31) and 67.7% (21/31), respectively (χ2=0.128, P=0.721). The Duration of silicone oil tamponade of the patients in the combined group was lower than that of the routine group (t=-41.962, P≤0.001). Postoperative logMAR BCVA values of patients in the combined group and the conventional group were 1.27±0.12 and 1.26±0.11, compared with the logMAR BCVA before surgery, each group was improved (t=19.947, t=-19.517, P≤0.001, P≤0.001). There was no significant difference in the logMAR BCVA between the eyes of the two groups (t=-0.394, P=0.695). The average numbers of operations on the eyes in the conventional group and the combined group were 2.39±0.62 and 2.06±0.25 times, the combined group had fewer operations on average (t=-2.705, P=0.009).
CONCLUSION: Intraoperative PPV treatment of MHRD with PS combined with PS marginal endolaser photocoagulation can effectively increase the rate of retinal reattachment after the first operation, reduce the number of repeated operations, and reduce the postoperative duration of silicone oil tamponade. 相似文献
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《Journal of vascular and interventional radiology : JVIR》2022,33(12):1476-1484.e2
PurposeTo evaluate temporal trends, practice variation, and associated outcomes with the use of intravascular ultrasound (US) during deep venous stent placement among Medicare beneficiaries.Materials and MethodsAll lower extremity deep venous stent placement procedures performed between January 1, 2017, and December 31, 2019 among Medicare beneficiaries were included. Temporal trends in intravascular US use were stratified by procedural setting and physician specialty. The primary outcome was a composite of 12-month all-cause mortality, all-cause hospitalization, or repeat target vessel intervention. The secondary outcome was a composite of 12-month stent thrombosis, embolization, or restenosis.ResultsAmong the 20,984 deep venous interventions performed during the study period, 15,184 (72.4%) utilized intravascular US. Moderate growth in intravascular US use was observed during the study period in all clinical settings. There was a variation in the use of intravascular US among all operators (median, 77.3% of cases; interquartile range, 20.0%–99.2%). In weighted analyses, intravascular US use during deep venous stent placement was associated with a lower risk of both the primary (adjusted hazard ratio, 0.72; 95% confidence interval [CI], 0.69–0.76; P < .001) and secondary (adjusted hazard ratio, 0.32; 95% CI, 0.27–0.39; P < .001) composite end points.ConclusionsIntravascular US is frequently used during deep venous stent placement among Medicare beneficiaries, with further increase in use from 2017 to 2019. The utilization of intravascular US as part of a procedural strategy was associated with a lower cumulative incidence of adverse outcomes after the procedure, including venous stent thrombosis and embolization. 相似文献
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目的研究阿克替苷对视网膜神经节细胞(RGC-5)的保护作用及其机制。方法将RGC-5细胞分为对照组、H_(2)O_(2)组、阿克替苷+H_(2)O_(2)组(1μmol·L^(-1)、10μmol·L^(-1)、30μmol·L^(-1)阿克替苷分别预处理细胞2 h),MTT法检测各组细胞活力;后续实验阿克替苷+H_(2)O_(2)组选择阿克替苷30μmol·L^(-1)作为治疗浓度,荧光探针H2DCF-DA检测活性氧(ROS)产生和罗丹明123检测线粒体膜电位,Western blot检测各组细胞中Bcl-2、Bcl-2/Bax、半胱氨酸蛋白酶-3(Caspase-3)蛋白表达。机制研究中首先用不同浓度阿克替苷单独处理RGC-5细胞24 h,Western blot检测血红素加氧酶-1(HO-1)蛋白表达水平,进一步锌原卟啉(ZnPP)预处理RGC-5细胞1 h,而后30μmol·L^(-1)阿克替苷单独预处理后与200μmol·L^(-1)H_(2)O_(2)共孵育24 h,通过MTT法测定细胞活力。结果与对照组相比,H_(2)O_(2)组中细胞活力明显降低(P<0.01)。与H_(2)O_(2)组相比,阿克替苷+H_(2)O_(2)组中10μmol·L^(-1)、30μmol·L^(-1)阿克替苷预处理可显著提高细胞活力(P<0.05、P<0.01)。与对照组相比,H_(2)O_(2)组RGC-5细胞ROS生成明显增加,线料体膜电位显著降低,同时Bcl-2/Bax比值降低和Caspase-3蛋白相对表达量增加(均为P<0.05)。与H_(2)O_(2)组相比,阿克替苷+H_(2)O_(2)组RGC-5细胞ROS生成减少,线粒体膜电位增加,Bcl-2/Bax比值提高,Caspase-3蛋白相对表达量减少(均为P<0.05)。与阿克替苷未处理组相比,阿克替苷剂量依赖性诱导HO-1蛋白的表达,与阿克替苷+H_(2)O_(2)组相比,加入ZnPP后细胞活力降低(P<0.01),说明HO-1抑制剂ZnPP降低了阿克替苷对H_(2)O_(2)损伤的抑制作用。结论阿克替苷能够通过上调HO-1表达抑制H_(2)O_(2)诱导的RGC-5氧化应激损伤。 相似文献