排序方式: 共有49条查询结果,搜索用时 15 毫秒
1.
目的:探讨基于T1WI(T1 weighted imaging)增强影像组学在术前无创鉴别高级别胶质瘤术后复发与假性进展的应用价值。方法:回顾性分析经病理证实为高级别胶质瘤的104例患者临床及磁共振成像资料,根据二次手术病理或神经肿瘤疗效评估标准(response assessment in neuro-oncology,RANO)将其分为复发组71例,假性进展组33例。按7∶3比例随机分为训练组和验证组。在T1WI增强图像上手动勾画肿瘤实质区的体积作为感兴趣区,用FeAture Explorer软件提取1 648个组学特征。 采用主成分分析(principal component analysis,PCA)及最小绝对收缩和选择算子(least absolute shrinkage and selection operator, LASSO)进行特征处理及筛选,采用支持向量机(support vector machine,SVM)构建影像组学模型。通过受试者工作特征曲线下面积(area under curve,AUC)及校准曲线评估模型的效能。结果:训练组鉴别高级别胶质瘤复发与假性进展的AUC为0.929, 准确率为 0.889,灵敏度为 72.7%,特异度为 100.0%。验证组的 AUC 为 0.853,准确率为 0.813,灵敏度为 90.9%,特异度为 71.4%。校准曲线显示模型预测值与实际值一致性较好。结论:基于T1WI增强影像组学模型具有较好的诊断效能,有助于鉴别高级别胶质瘤术后复发与假性进展。 相似文献
5.
目的:探讨基于胸部CT测量的肺小血管参数在评估肺动脉高压(pulmonary hypertension,PH)分型及结缔组织疾病相关肺高压(connective tissue diseases-related pulmonary hypertension,CTD-PH)严重程度分级中的临床价值。方法:回顾性纳入 170例PH患者,包括60例CTD-PH患者、52例特发性PH(idiopathic pumonary hypertension,IPAH)患者和58例慢性阻塞性肺疾病相关 PH(chronic obstructive pulmonary disease-rebated pulmonary hypertension,COPD-PH)患者,同时纳入 120 例健康受试者 (health control,HC)作为对照。基于胸部CT测量横截面面积(cross-sectional area,CSA)<5 mm2 的肺小血管CSA之和及CSA 5~ 10 mm2 的肺小血管CSA之和与肺总CSA的比率(%CSA<5和%CSA5-10),采用单因素方差分析或Kruskal-Wallis检验比较4组之间%CSA<5和%CSA5-10的差异,并进行组间两两比较。采用受试者工作特征(receiver operating characteristic,ROC)曲线分析% CSA区分重度CTD-PH(CTD-S-PH组)和中重度CTD-PH(CTD-LM-PH组)的能力,计算曲线下面积(area under curve,AUC)、灵敏度及特异度。结果:与HC组比较,IPAH组和COPD-PH组的%CSA<5均小于HC组(P均<0.001),COPD-PH组的%CSA5-10低于 HC组(P=0.038),而CTD-PH和IPAH组的%CSA5-10均显著高于HC组(P均< 0.05)。不同类型PH组间比较,CTD-PH的%CSA<5 和%CSA5-10均高于COPD-PH组(P均<0.001),IPAH组的%CSA5-10显著高于CTD-PH组(P=0.022),而IPAH和COPD-PH组的% CSA<5差异无统计学意义(P= 0.833)。CTD-S-PH 组患者的%CSA<5显著低于 CTD-LM-PH 组(P=0.004)。ROC 曲线分析结果显示,%CSA<5预测 CTD-S-PH的最佳截断值为0.804,AUC为0.710(95%CI:0.573~0.847),灵敏度为0.714,特异度为0.320。结论:基于胸部CT定量的肺小血管参数%CSA可以区分不同类型PH。在CTD-PH人群中,%CSA<5可作为评估PH严重程度分级的参考依据。 相似文献
6.
目的:观察神经电生理检查对面神经麻痹患者的诊断意义。方法:瞬目反射和肌电(EMG)的常规检测方法。结果:瞬目反射主要表现为患者R1,R2波出波率明显减少,波幅降低,潜伏期延长。EMG所检的52例病例中,异常40例,阳性率76.9%,表现为患侧额肌或口轮匝肌出现失神经电位。结论:根据患者自身的情况选择瞬目反射或是肌电(EMG),就能为临床提供准确的诊断和治疗的帮助。 相似文献
7.
9.
全身MRI与核素骨扫描对骨转移瘤诊断价值的对照研究 总被引:1,自引:0,他引:1
目的 评价全身MRI对骨转移瘤的诊断价值.方法 对30例经病理证实的恶性肿瘤患者在2周内分别进行伞身MRI及核素骨显像(BS),采取临床资料同常规MRI、CT等多种影像资料结合分析,辅以必要的随访复查为"金标准",分别以30例患者和270个部位为单位进行分析.使用McNemar检验比较两者对骨转移瘤诊断的敏感度、特异度.结果 30例患者中,"金标准"诊断27例患者存在骨转移,全身MRI检出25例,2例假阴性,无假阳性患者;BS检出27例阳性患者,其中2例为假阳性.以病例为单位,两者的敏感度均为92.6%(25/27),特异度分别为100%(3/3)及33.3%(1/3).ROC曲线下面积分别为0.9630及0.6296,差异无统计学意义(P>0.05).以病灶部位为单位统计显示全身MRI的敏感度、特异度分别为90.8%(108/119)、98.0%(148/151),高于骨扫描的70.6%(84/119)、90.7%(137/151)(P值均<0.01).全身MRI的ROC曲线下面积为0.9438,大于BS的0.8066(P<0.01).全身MRI同时发现3例患者存在脑转移,4例患者存在肺转移,4例患者存在肝转移.结论 全身MRI对骨转移瘤的综合诊断能力较Bs好,具有一定的临床应用价值.Abstract: Objective The aim of the study was to evaluate the reliability of whole-body MRI(WBMRI)in detecting osseous metastases.Methods Thirty patients verified with malignant tumor by histology were enrolled.All the patients underwent WB-MRI and bone scintigraphy(BS)with a two week interval.Clinical information,conventional MRI and CT images,and follow-up data were collected as gold standard for the diagnosis of bone metastases.The data of 30 patients and 270 segments as study unit respectively were analyzed.The sensitivity and specificity between WB-MRI and BS were compared with McNemar test.Resuits Bone metastases were confirmed in 27 of 30 patients by gold standard.Twenty-five patients with bone metastases were detected by WB-MRI and no false-positive cases.Twenty-seven patients with bone metastases were Nund by BS but having two false-positive oases.With patients as study unit,the diagnostic sensitivity of WB-MRI and BS were both 92.6%(25/27)and the specificity were 100%(3/3)and 33.3%(1/3),respectively.The area under ROC curve of WB-MRI and BS were 0.9630 and 0.6296,respectively(P>0.05).With segments as study unit,119 bone metastases segments were confirmed.The diagnostic sensitivity of WB-MRI and BS were 90.8%(108/119)and 70.6%(84/119)(P<0.01),while the specificity were 98.0%(148/151)and 90.7%(137/151),respectively(P<0.01).The area under ROC curve of WB-MRI and BS were 0.9438 and 0.8066.The former was obviously higher than the latter(P<0.01).Meauwhile.by WB-MRI,3 cases coexisting with brain metastases,4 cases with lung metastases,and 4 cases with hepatic metastases were found.Conclusion WB-MRI was a good tool for screening osseous metastases. 相似文献
10.
目的:探讨症状性颅内动脉粥样硬化性疾病(intracranial atherosclerotic disease,ICAD)患者前循环低灌注与缺血性卒中复发的相关性。方法:回顾性分析130例由大脑中动脉狭窄引发的症状性ICAD患者,根据急性缺血性卒中事件发生次数将其分为初发组(n=92)和复发组(n=38),基于残余功能达峰时间(time to maximum of the residual function,Tmax)阈值Tmax>4 s及Tmax>6 s定量低灌注体积。采用独立样本t检验、非参数检验、卡方检验或Fisher精确概率法对比分析两组患者大脑中动脉狭窄率、分水岭梗死发生率、Tmax> 6 s及Tmax> 4 s的低灌注体积,多因素Logistic回归探讨缺血性卒中复发相关的独立危险因素,并进行ROC曲线分析。结果:与初发组相比,复发组血管狭窄率更高(P=0.003)、分水岭梗死发生比例更高(P=0.037)、Tmax>6 s及Tmax>4 s 的低灌注体积更高(P值均<0.001),其中Tmax>4 s的低灌注体积是与缺血性卒中复发相关的独立危险因素(OR=1.120,低灌注体积每增加10 mL,95% CI:1.051~1.194,P<0.001),ROC曲线下面积为0.756(95% CI:0.672~0.839),灵敏度76.3%,特异度63.0%。结论:基于时间阈值Tmax>4 s量化的低灌注体积,是前循环症状性ICAD患者卒中复发的独立危险因素,可能成为预警缺血性卒中复发的有效影像学标志物。 相似文献