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31.
PurposeTo quantify joint degeneration and the clinical outcome after curettage and cementation in subchondral giant cell tumors of the bone (GCTB) at the knee.MethodsWe conducted a retrospective analysis of 14 consecutive patients (seven female, seven male) with a mean age of 34 years (range 19–51) who underwent curettage and subchondral cementation for a biopsy-confirmed GCTB at the distal femur or the proximal tibia between August 2001 and August 2017, with a mean follow-up period of 54.6 months (range 16.1–156 months). The Whole-Organ Magnetic Resonance Imaging Score (WORMS), Kellgren-Lawrence (KL) classification, and Musculo-Skeletal Tumor Society (MSTS) score were assessed.ResultsRadiological degeneration progressed from preoperative to the latest follow-up, with a median WORMS from 2.0 to 4.0 (p = 0.006); meanwhile, the median KL score remained at 0 (p = 0.102). Progressive degeneration (WORMS) tended to be associated with the proximity of the tumor to the articular cartilage (mean 1.57 mm; range 0–12 mm) (p = 0.085). The most common degenerative findings were cartilage lesions (n = 11), synovitis (n = 5), and osteophytes (n = 4). Mean MSTS score increased from 23.1 (preoperatively) to 28.3 at the latest follow-up (p < 0.01).Seven patients (50%) were treated for a local recurrence, with six revision surgeries performed. Removal of the cement spacer and filling of the cavity with a cancellous autograft was performed in seven patients. Conversion to a total knee arthroplasty was performed in one patient for local tumor control.ConclusionsCementation following the curettage of GCTB around the knee is associated with slight degeneration at medium-term follow-up and leads to a significant reduction in pain. Removal of the cement and reconstruction with an autograft may be beneficial in the long term.  相似文献   
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BackgroundThe epidemiology and clinical characteristics of spinal epidural lipomatosis (SEL) have been well-reported in the literature. However, few studies investigated the concomitant spinal pathologies that were present in patients with SEL. Therefore, we aimed to summarize the clinical and radiological characteristics of patients with SEL diagnosed on spinal imaging.MethodsPatients who were diagnosed with SEL on magnetic resonance imaging from January 2018 to October 2020 at our institution were included in the study. Clinical data was collected using a standardized data collection form. SEL was graded using a modified version of the Borré grading system. Factors associated with moderate or severe SEL were determined using multiple logistic regression.ResultsA total of 90 patients were included in the analysis. The mean (±SD) age was 59.3 (±17.1) years, and 62 patients (68.9%) were male. 61 patients (67.8%) had moderate or severe SEL. Most patients were overweight or obese (57 patients, 63.3%). The most common presenting symptoms was back pain (57 patients, 63.3%). SEL was diagnosed incidentally in 42 patients (46.7%). The lumbar spine was the most common site of SEL (35 patients, 38.9%). The most common concomitant spinal pathologies were disc bulge (83 patients, 92.2%) and flavum hypertrophy (60 patients, 66.7%). Moderate or severe SEL was associated with WHO Obesity Class, back pain or radicular leg pain at first presentation, and SEL that was worst at the lumbar or lumbosacral spinal level.ConclusionsModerate or severe SEL were independently associated with WHO Obesity Class, back pain, radicular leg pain, and SEL that was worst at the lumbar or lumbosacral spinal level. Future studies should prospectively evaluate whether weight loss therapy is warranted in patients with SEL.  相似文献   
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Intratumor heterogeneity is a main cause of the dismal prognosis of glioblastoma (GBM). Yet, there remains a lack of a uniform assessment of the degree of heterogeneity. With a multiscale approach, we addressed the hypothesis that intratumor heterogeneity exists on different levels comprising traditional regional analyses, but also innovative methods including computer-assisted analysis of tumor morphology combined with epigenomic data. With this aim, 157 biopsies of 37 patients with therapy-naive IDH-wildtype GBM were analyzed regarding the intratumor variance of protein expression of glial marker GFAP, microglia marker Iba1 and proliferation marker Mib1. Hematoxylin and eosin stained slides were evaluated for tumor vascularization. For the estimation of pixel intensity and nuclear profiling, automated analysis was used. Additionally, DNA methylation profiling was conducted separately for the single biopsies. Scoring systems were established to integrate several parameters into one score for the four examined modalities of heterogeneity (regional, cellular, pixel-level and epigenomic). As a result, we could show that heterogeneity was detected in all four modalities. Furthermore, for the regional, cellular and epigenomic level, we confirmed the results of earlier studies stating that a higher degree of heterogeneity is associated with poorer overall survival. To integrate all modalities into one score, we designed a predictor of longer survival, which showed a highly significant separation regarding the OS. In conclusion, multiscale intratumor heterogeneity exists in glioblastoma and its degree has an impact on overall survival. In future studies, the implementation of a broadly feasible heterogeneity index should be considered.  相似文献   
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钟凯华 《安徽医药》2022,26(11):2265-2269
目的分析长臂单轴椎弓根螺钉经 Wiltse入路在单纯性胸腰椎压缩性骨折中的应用效果及对肌肉损伤的影响。方法选取自 2018年 1月至 2020年 8月周口市中心医院收治的单纯性胸腰椎压缩性骨折病人 87例,根据复位固定术式不同,分为观察组 38例、对照组 49例,其中观察组采取长臂单轴椎弓根螺钉经 Wiltse入路,对照组采取 AF系统经传统后正中入路。记录两组病人围术期指标、手术前后血清肌肉损伤指标[肌酸激酶( CK)、肌红蛋白( Mb)]变化;采用疼痛视觉模拟评分( VAS)评价病人不同时间节点疼痛水平;经胸腰椎正侧位片检查获取伤椎原始高度( H0)、术前及术后 1周伤椎椎体前缘高度( H1H2),计算术前、术后 1周伤椎相对高度( H1/H0、H2/H0)及伤椎复位率,并测量矢状位 Cobb角变化;随访 3个月,采用 Oswestry功能障、碍指数( ODI)评价功能障碍情况,并统计手术相关并发症。结果观察组手术时长、术中失血量、术后引流量及首次下床活动时间均明显短于或低于对照组( P<0.05)。术后 3d,两组血清 CK、Mb水平均较术前升高( P<0.05),且观察组血清 CK、Mb水平  相似文献   
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BackgroundMachine learning has been applied to improve diagnosis and prognostication of acute traumatic spinal cord injury. We investigate potential for clinical integration of machine learning in this patient population to navigate variability in injury and recovery.Materials and methodsWe performed a systematic review using PRISMA guidelines through PubMed database to identify studies that use machine learning algorithms for clinical application toward improvements in diagnosis, management, and predictive modeling.ResultsOf the 132 records identified, a total of 13 articles met inclusion criteria and were included in final analysis. Of the 13 articles, 5 focused on diagnostic accuracy and 8 were related to prognostication or management of traumatic spinal cord injury. Across studies, 1983 patients with spinal cord injury were evaluated with most classifying as ASIA C or D. Retrospective designs were used in 10 of 13 studies and 3 were prospective. Studies focused on MRI evaluation and segmentation for diagnostic accuracy and prognostication, investigation of mean arterial pressure in acute care and intraoperative settings, prediction of ambulatory and functional ability, chronic complication prevention, and psychological quality of life assessments. Decision tree, random forests (RF), support vector machines (SVM), hierarchical cluster tree analysis (HCTA), artificial neural networks (ANN), convolutional neural networks (CNN) machine learning subtypes were used.ConclusionsMachine learning represents a platform technology with clinical application in traumatic spinal cord injury diagnosis, prognostication, management, rehabilitation, and risk prevention of chronic complications and mental illness. SVM models showed improved accuracy when compared to other ML subtypes surveyed. Inherent variability across patients with SCI offers unique opportunity for ML and personalized medicine to drive desired outcomes and assess risks in this patient population.  相似文献   
37.
目的探究可拆卸经鼻垂体腺瘤切除操作模型的真实性,并初步探讨了模型的教学性。方法利用患者CT建模、精细优化及3D打印技术构建可拆卸垂体腺瘤切除模型。评估者为19名来自北京协和医院的本院及进修医师,其中年资<10分入"低年资组";年资≥10分入"高年资组"。每位医师分别对3D打印垂体腺瘤切除模型进行操作,并于操作前后分别填写调查问卷、评估量表。结果高年资组的探查经验均高于低年资组。真实度项目的得分均在4附近,各评分项间无明显差异;"切除垂体腺瘤"步骤的真实性评分相对较低;高年资组评分普遍低于低年资组。操作前低年资组信心评分显著低于高年资组,操作后两组评分趋于一致;低年资组的垂体腺瘤切除信心评分变化显著高于高年资组(P<0.05)。结论该模型具有较高的真实性,可用于教学试验进一步评估教学效果。  相似文献   
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卵巢硬化性间质瘤是一种临床罕见的卵巢良性肿瘤,其发病率低,病因不明确,以年轻女性多见,多为单侧肿块,常因月经不规则出血或体检发现腹部包块而就诊。影像学检查可见“湖岛征”、“快进慢出”和“向心性强化”等改变。病理组织学见单侧类圆形囊实性肿块,“假小叶”为特征性病变。免疫组织化学可见抑制素、波形蛋白和肌动蛋白等阳性表达。确诊主要通过病理组织学诊断,影像学检查具有重要参考价值。术前诊断困难,容易与卵巢纤维瘤、卵泡膜细胞瘤、卵巢库肯勃瘤和颗粒细胞瘤等相混淆。手术治疗为主要治疗手段,多采用患侧肿瘤切除术或附件切除术,术后预后较好,卵巢功能可恢复正常。对于肿瘤细胞出现核分裂象和坏死较多时,需警惕复发风险,建议长期跟踪随访。  相似文献   
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