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arXiv 1903.03386cs.LGq-bio.QMstat.ML
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基于事件模型的高维影像生物标记物对痴呆空间进展的评估

Event-Based Modeling with High-Dimensional Imaging Biomarkers for Estimating Spatial Progression of Dementia

Erasmus MC(伊拉斯姆斯医学中心);Delft University of Technology(代尔夫特理工大学);University of Copenhagen(哥本哈根大学)

Vikram Venkatraghavan, Florian Dubost, Esther E. Bron, Wiro J. Niessen, Marleen de Bruijne, Stefan Klein

摘要:

基于事件的模型(EBM)是一类疾病进展模型,可用于从横截面数据估计神经病理学变化的时间顺序。目前的EBM仅处理标量生物标志物,如区域体积,作为输入。然而,区域聚集是基本高分辨率图像的粗略总结,可能限制EBM的准确性。因此,我们提出了一种新的方法,利用高维体素成像生物标志物:n维判别EBM(nDEBM)。nDEBM是基于这样一种见解,即混合建模,这是传统EBM的关键要素,可以由更具可扩展性的半监督支持向量机(SVM)方法取代。该SVM用于估计每个区域的异常程度,然后用于获得受试者特异性疾病进展模式。这些模式反过来又用于估计的平均排序通过拟合广义马洛模型。为了验证使用nDEBM获得的生物标志物排序,我们还提出了一个模拟成像生物标志物的时间演化(SImBioTE)的框架,模拟大脑区域的神经变性。SImBioTE在不同的大脑区域独立训练变分自动编码器(VAE),以模拟疾病进展的不同阶段的图像。我们还使用阿尔茨海默病神经影像学倡议(ADNI)的数据在临床上验证了nDEBM。在这两个实验中,使用高维特征的nDEBM比使用区域体积生物标志物的最先进的EBM方法具有更好的性能。这表明nDEBM是一种有前途的疾病进展建模方法。

英文摘要:

Event-based models (EBM) are a class of disease progression models that can be used to estimate temporal ordering of neuropathological changes from cross-sectional data. Current EBMs only handle scalar biomarkers, such as regional volumes, as inputs. However, regional aggregates are a crude summary of the underlying high-resolution images, potentially limiting the accuracy of EBM. Therefore, we propose a novel method that exploits high-dimensional voxel-wise imaging biomarkers: n-dimensional discriminative EBM (nDEBM). nDEBM is based on an insight that mixture modeling, which is a key element of conventional EBMs, can be replaced by a more scalable semi-supervised support vector machine (SVM) approach. This SVM is used to estimate the degree of abnormality of each region which is then used to obtain subject-specific disease progression patterns. These patterns are in turn used for estimating the mean ordering by fitting a generalized Mallows model. In order to validate the biomarker ordering obtained using nDEBM, we also present a framework for Simulation of Imaging Biomarkers' Temporal Evolution (SImBioTE) that mimics neurodegeneration in brain regions. SImBioTE trains variational auto-encoders (VAE) in different brain regions independently to simulate images at varying stages of disease progression. We also validate nDEBM clinically using data from the Alzheimer's Disease Neuroimaging Initiative (ADNI). In both experiments, nDEBM using high-dimensional features gave better performance than state-of-the-art EBM methods using regional volume biomarkers. This suggests that nDEBM is a promising approach for disease progression modeling.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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