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ObjectiveTo evaluate the performance of a deep learning (DL)-based radiomics strategy on contrast-enhanced computed tomography (CT) to predict microvascular invasion (MVI) status and clinical outcomes, recurrence-free survival (RFS) and overall survival (OS) in patients with early stage hepatocellular carcinoma (HCC) receiving surgical resection.MethodsAll 283 eligible patients were included retrospectively between January 2008 and December 2015, and assigned into the training cohort (n = 198) and the testing cohort (n = 85). We extracted radiomics features via handcrafted radiomics analysis manually and DL analysis of pretrained convolutional neural networks via transfer learning automatically. Support vector machine was adopted as the classifier. A clinical-radiological model for MVI status integrated significant clinical features and the radiological signature generated from the radiological model with the optimal area under the receiver operating characteristics curve (AUC) in the testing cohort. Otherwise, DL-based prognostic models were constructed in prediction of recurrence and mortality via Cox proportional hazard analysis.ResultsThe clinical-radiological model for MVI represented an AUC of 0.909, accuracy of 96.47%, sensitivity of 90.91%, specificity of 97.30%, positive predictive value of 83.33%, and negative predictive value of 98.63% in the testing cohort. The clinical-radiological models for identification of RFS and OS outperformed prediction performance of the clinical model or the DL signature alone. The DL-based integrated model for prognostication showed great predictive value with significant classification and discrimination abilities after validation.ConclusionsThe integrated DL-based radiomics models achieved accurate preoperative prediction of MVI status, and might facilitate predicting tumor recurrence and mortality in order to optimize clinical decisions for patients with early stage HCC.  相似文献   
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《Neuro-Chirurgie》2023,69(3):101428
BackgroundRodent models are commonly used experimentally to assess treatment effectiveness in spinal fusion. Certain factors are associated with better fusion rates. The objectives of the present study were to report the protocols most frequently used, to evaluate factors known to positively influence fusion rate, and to identify new factors.MethodA systematic literature search of PubMed and Web of Science found 139 experimental studies of posterolateral lumbar spinal fusion in rodent models. Data for level and location of fusion, animal strain, sex, weight and age, graft, decortication, fusion assessment and fusion and mortality rates were collected and analyzed.ResultsThe standard murine model for spinal fusion was male Sprague Dawley rats of 295 g weight and 13 weeks’ age, using decortication, with L4-L5 as fusion level. The last two criteria were associated with significantly better fusion rates. On manual palpation, the overall mean fusion rate in rats was 58% and the autograft mean fusion rate was 61%. Most studies evaluated fusion as a binary on manual palpation, and only a few used CT and histology. Average mortality was 3.03% in rats and 1.56% in mice.ConclusionsThese results suggest using a rat model, younger than 10 weeks and weighing more than 300 grams on the day of surgery, to optimize fusion rates, with decortication before grafting and fusing the L4-L5 level.  相似文献   
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目的:探讨复杂骨盆骨折手术治疗中3D打印骨折模型的应用方法及效果。方法:选取医院收治的60例复杂骨盆骨折患者,按照随机数表法将其分为对照组和观察组,每组30例。对照组行传统CT指导下手术治疗,观察组行3D打印仿真骨盆模型体外模拟术后,应用腹直肌旁切口钢板内固定术治疗。比较两组手术时间、住院时间和骨折愈合时间,以及术中出血量、并发症发生率和骨盆功能恢复优良率。结果:观察组手术时间、住院时间及骨折愈合时间短于对照组,术中出血量少于对照组,差异有统计学意义(t=2.721,t=2.458,t=2.791,t=4.450;P<0.05);观察组和对照组并发症发生率分别为3.33%和10.00%,差异无统计学意义(x2=0.267,P>0.05);观察组和对照组骨盆功能恢复优良率分别为96.67%和73.33%,观察组明显高于对照组,差异有统计学意义(x2=4.705,P<0.05)。结论:复杂骨盆骨折手术中应用3D打印骨折模型可缩短手术时间、住院时间,减少出血量,促进骨折愈合,可改善骨盆功能且并发症少。  相似文献   
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PurposeThe purpose of this study was to analyze the management and outcomes of primary button battery ingestions and their sequelae at a single high-volume center, and to propose a risk score to predict the likelihood of a severe outcome.MethodsThe medical record was queried for all patients under 21 years old evaluated at our institution for button battery ingestion from 2008 to 2021. A severe outcome was defined as having at least one of the following: deep/circumferential mucosal erosion, perforation, mediastinitis, vascular or airway injury/fistula, or development of esophageal stricture. From a selection of clinically relevant factors, logistic regression determined predictors of a severe outcome, which were incorporated into a risk model.Results143 patients evaluated for button battery ingestion were analyzed. 24 (17%) had a severe outcome. The independent predictors of a severe outcome in multivariate analysis were location of battery in the esophagus on imaging (96%), battery size >/ = 2 cm (95%), and presence of any symptoms on presentation (96%), with P < 0.001 in all cases. Predicted probability of a severe outcome ranged from 88% when all three risk factors were observed, to 0.3% when none were present.ConclusionWe report the presentation, management, and complication profiles of a large cohort of BB ingestions treated at a single institution. A risk score to predict severe outcomes may be used by providers initially evaluating patients with button battery ingestion in order to allocate resources and expedite transfer to a center with pediatric endoscopic and surgical capabilities.Level of evidenceLevel IV.Type of studyClinical Research Paper.  相似文献   
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目的 评价CT引导下经皮二次穿刺活检用于明确诊断肺部病变的可行性及安全性。方法 回顾性分析40例接受2次肺穿刺活检患者的临床、影像学及随访资料,根据最终诊断结果,比较2次活检的诊断准确率,分析并发症及初次活检误诊的危险因素。结果 40例中,17例初次活检诊断结果与最终诊断一致(确诊组)、23例诊断不一致(误诊组),诊断准确率为42.50%(17/40),并发症发生率为27.50%(11/40);39例二次活检诊断结果与最终诊断一致,诊断准确率为97.50%(39/40),并发症发生率为25.00%(10/40)。二次活检诊断准确率明显提高,并发症发生率与初次活检差异无统计学意义(P>0.05)。组间病灶性质和气胸发生率差异均有统计学意义(P均<0.05)。结论 CT引导下经皮二次穿刺活检用于明确诊断肺部病变安全、可行。  相似文献   
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