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1.
PurposeTo examine predictors of midterm occlusion in portal and hepatic veins within or adjacent to the ablation zone after irreversible electroporation (IRE) of liver tumors.Materials and MethodsThis retrospective cohort analysis included 39 patients who underwent CT-guided IRE of liver tumors. Vessels within or adjacent to the ablation zone were identified on CT images acquired immediately after the procedure, and the positional relationships with the ablation zone (within/adjacent), locations (proximal/distal), and diameters (< 4 mm or ≥ 4 mm) were evaluated. Using contrast-enhanced follow-up scans, each vessel was classified as patent, stenosed, or occluded. Associations between vessel occlusion and each variable were investigated.ResultsOverall, 33 portal veins and 64 hepatic veins were analyzed. Follow-up scans showed occlusion in 12/33 (36.7%) portal veins and 17/64 (26.6%) hepatic veins. Vessels within the ablation zone were occluded significantly more frequently than vessels adjacent to the ablation zone (portal: 55.6% [10/18] vs 13.3% [2/15], P = .04; hepatic: 45.4% [15/33] vs 6.4% [2/31], P = .011). Vessels with a diameter < 4 mm were also occluded significantly more frequently than vessels with a diameter ≥ 4 mm (portal: 72.7% [8/11] vs 18.1% [4/22], P = .011; hepatic: 54.8% [17/31] vs 0% [0/33], P < .001). The respective positive and negative predictive values for occlusion of vessels categorized as both within and < 4 mm were 88% (7/8) and 82% (20/25) for portal veins and 79% (15/19) and 96% (43/45) for hepatic veins.ConclusionsMidterm vessel occlusion after liver IRE could be predicted with relatively high accuracy by assessing ablation location and vessel diameter.  相似文献   
2.
ObjectivePrevious studies on glioblastomas (GBMs) have not reached a consensus on peritumoral edema (PTE)’s influence on survival. This study evaluated the PTE index’s prognostic role in newly diagnosed GBMs using a well-designed method.MethodsSelected patients were reviewed after a rigorous screening process. Their general information was obtained from electronic medical records. The imaging metrics (MTD, TTM, TTE) representing tumor diameter, laterality, and PTE extent were obtained by manual measurement in Syngo FastView software. The PTE index was a ratio of TTE to MTD. Multiple variables were evaluated using analysis of variance and Cox regression model.ResultsOf 143 patients, 62 were included in this study. MGMT promoter methylation and tumor laterality were both independent prognostic factors (p = 0.020, 0.042; HR = 0.272, 2.630). The lateral tumors’ index was higher than that of the medial tumors (57.7% vs. 42.6%, p = 0.027). Low-index tumors were located in relatively medial positions compared with high-index tumors (TTM, 4.9 vs. 12.8, p = 0.032). This finding indicated that the PTE index tended to increase with tumor laterality. Moreover, the patients with low-index tumors had a significant survival disadvantage in the univariate analysis but not in the multivariate analysis (p = 0.023, 0.220). However, further analysis found that the combination of tumor laterality and PTE statistically stratified the survival outcome. The patients with lateral high-index tumors survived significantly longer (p = 0.022, HR = 1.927).ConclusionsIn contrast with the previous studies, this study recommends combining PTE and tumor laterality for survival stratification in newly diagnosed GBMs.  相似文献   
3.
《Injury》2021,52(4):705-712
Intramedullary nails are the common treatment options for femoral intertrochanteric fractures. However, aseptic loosening is considered to be one of the primary forms of failure that can be caused by the stress shielding between the bone and implants. The matching in mechanical properties of implant and bone is a key issue to prevent this failure. Polyetheretherketone (PEEK) and Function-graded (FG) materials are widely used in clinical because of their excellent mechanical properties. In this study, to investigate the biomechanical behaviors of intramedullary nails made of Ti-6Al-4V alloy, Stainless Steel (SS), PEEK and two FG materials, three-dimensional finite element models of intertrochanteric fracture femur with intramedullary nail were constructed with ABAQUS. The maximum von Mises stress on the femoral fracture surface fixed by PEEK intramedullary nail was the largest, followed by FG intramedullary nail, which help stimulate bone growth and subsequently reduce fracture healing time. Compared with traditional metal intramedullary nails, PEEK and FG implants might increase von Mises stress along the same path in the proximal femur. The results showed that PEEK and FG intramedullary nails obviously changed the stress distributions in the bone and reduced stress shielding. This finding indicated that PEEK and FG intramedullary nails have the potential to become alternatives to the conventional metal intramedullary nails.  相似文献   
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5.
输卵管卵巢脓肿的CT诊断价值   总被引:11,自引:0,他引:11  
目的 总结分析女性输卵管卵巢脓肿的CT特征,以寻求和探讨鉴别诊断依据及CT诊断的价值。方法 回顾性分析10例输卵管卵巢脓肿患者CT腹盆腔增强扫描资料。结果 10例患者CT均显示附件区厚壁囊性或囊实混合性肿块,肿块外缘模糊毛糙,增强多见脓肿壁呈厚壁分层强化及内部强化分隔。其他伴随的CT表现:子宫骶骨韧带增厚9例,直肠周围、骶前脂肪密度增高模糊9例,显示输卵管扩张积脓或积液的管状结构影6例,宫腔积液4例。CT观察到脓肿与盆腔结构粘连包括:肿块与子宫粘连者9例,与直肠、乙状结肠粘连者4例,与盆腔小肠肠管及盆壁结构广泛粘连3例;显示腹膜增厚伴腹水及右侧输卵管卵巢脓肿伴阑尾炎各2例。结论 CT除了能观察附件区囊实性肿块,还能显示相邻盆腔器官的受累粘连及盆底软组织或筋膜层的炎性浸润,能对附件脓肿做定性和定位诊断,对诊断不清的可疑妇科感染有鉴别价值。  相似文献   
6.
目的为了探索一套适合我国社区卫生服务机构持续健康发展的护理管理模式,以提高社区护理管理效应。通过专家评定法以及全体护理人员讨论的方法,给予每项护理工作以适当的权重,以此建立社区护理工作绩效量化评价体系,并组织实施。实施后,在社区护理工作方面形成了良好的管理导向,建立了有效的激励机制,提高了护理工作质量、效率和效益。因此,可以认为在社区护理实施工作绩效量化评价体系,是值得推广的一项举措。  相似文献   
7.
高血压的社区管理与医院内科门诊管理效果比较   总被引:6,自引:1,他引:5  
目的 评价健康教育在社区高血压患者管理中的效果。方法 随机抽取北京复兴医院月坛社区卫生服务中心管理的高血压患者603例作为研究对象,以同期该院三里河内科门诊就诊的高血压患者617例作为对照,进行血压测量和问卷调查。结果 社区高血压患者高血压知识知晓率明显好于内科门诊高血压患者(P<0.01);其生活方式(遵医行为、体育锻炼、食盐量等)较好;血压控制情况也好于门诊患者(P<0.01)。结论 规范、定期的健康教育可以提高高血压患者对高血压知识的知晓情况,改善高血压患者的不良行为习惯;利用社区卫生服务站固定的合作关系及新型医患模式有利于健康教育、健康知识普及和取得治疗成效。  相似文献   
8.
目的探索以虚拟现实技术为基础的枢椎椎弓根螺钉置人方法。方法选取8具成人颅一颈椎标本,采用改良四柱式定位框架固定于枕颈,使颅-颈-肩形成统一刚体,保持空间位置恒定,CT薄层扫描获取枢椎三维定位信息,采用Aero—Tech立体定向手术规划系统三维建模,设计安全、可视化、个体化的虚拟置钉路径,反复虚拟演示验证钉道安全后,导向弓把持下置人导向钢针,复查CT评价置钉的准确性。结果16个枢椎椎弓根置钉过程中,方向出现偏差(横突孔突破)1个,失败率为6.25%。结论目标椎弓根的容积三维重建、置钉路径可视化设计和虚拟演示,使操作过程简单、直观而精确,不需要线形和角性参数的测量;加上导向抓持装置提供的稳定性,使该技术具有很好的临床应用前景。  相似文献   
9.
有限内固定结合外固定支架治疗胫骨远端骨折   总被引:5,自引:2,他引:3  
目的探讨有限内固定结合Hybrid外固定支架治疗胫骨远端骨折的疗效。方法从2003年1月~2005年7月,使用Hybird外固定支架治疗胫骨远端骨折21例,按AO分类:A1型4例;A2型5例;A3型4例;C1型2例;C2型3例;C3型3例,其中开放性骨折8例,手术采用有限切开,骨片钉固定,Hybrid外固定支架不跨踝关节固定。结果术后21例均获随访,平均随访时间12.3个月,骨折平均愈合时间7.6个月。功能评定采用Bone的踝关节活动度进行评价,优良率达76%。结论Hybrid外固定支架设计合理并能维持骨干的轴线,骨片钉能很好的固定骨折块,同时避免了软组织的并发症,可使踝关节早期活动,防止踝关节僵硬,因而是治疗胫骨远端骨折有效的方法之一。  相似文献   
10.
原发性乳腺恶性淋巴瘤的诊断及外科治疗探讨   总被引:2,自引:0,他引:2  
目的探讨原发性乳腺恶性淋巴瘤的诊断与治疗. 方法回顾性分析我院1992~2004年5例原发性乳腺恶性淋巴瘤的临床资料.5例均为术后组织学病理诊断.4例行乳腺癌改良根治术,1例行乳房单纯切除术.5例均行化疗及放疗. 结果乳腺癌改良根治术手术时间60~120 min,平均80 min;乳房单纯切除术加乳腔镜腋窝淋巴结清扫术手术时间75 min.术中出血量150~250 ml,平均200 ml.术后病理组织诊断均为弥漫性非霍奇金氏淋巴瘤,为B细胞来源.且均有腋窝淋巴结转移.全组病例随访6个月~12年,平均4.5年.2例II期,均死于肿瘤多器官转移;3例I期,肿瘤无复发. 结论原发性乳腺恶性淋巴瘤无明显特异性表现,术前诊断困难.钼靶X线照相,对诊断有帮助. 治疗可选择手术、放疗、化疗或单纯给予化疗和放疗.  相似文献   
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