Martínez Vera Naira P, Höller Johannes, Widek Thomas, Neumayer Bernhard, Ehammer Thomas, Urschler Martin
Ludwig Boltzmann Institute for Clinical Forensic Imaging, Universitätsplatz 4, 8010 Graz, Austria; BioTechMed-Graz, Graz, Austria.
Ludwig Boltzmann Institute for Clinical Forensic Imaging, Universitätsplatz 4, 8010 Graz, Austria.
Forensic Sci Int. 2017 Aug;277:21-29. doi: 10.1016/j.forsciint.2017.05.005. Epub 2017 May 12.
Forensic age estimation research based on skeletal structures focuses on patterns of growth and development using different bones. In this work, our aim was to study growth-related evolution of the manubrium in living adolescents and young adults using magnetic resonance imaging (MRI), which is an image acquisition modality that does not involve ionizing radiation. In a first step, individual manubrium and subject features were correlated with age, which confirmed a statistically significant change of manubrium volume (M:p<0.01, R¯=0.50) and surface area (M:p<0.01, R¯=0.53) for the studied age range. Additionally, shapes of the manubria were for the first time investigated using principal component analysis. The decomposition of the data in principal components allowed to analyse the contribution of each component to total shape variation. With 13 principal components, ∼96% of shape variation could be described (M:p<0.01, R¯=0.60). Multiple linear regression analysis modelled the relationship between the statistically best correlated variables and age. Models including manubrium shape, volume or surface area divided by the height of the subject (Y∼MM/S:p<0.01, R¯=0.71; Y∼MM/S:p<0.01, R¯=0.72) presented a standard error of estimate of two years. In order to estimate the accuracy of these two manubrium-based age estimation models, cross validation experiments predicting age on held-out test sets were performed. Median absolute difference of predicted and known chronological age was 1.18 years for the best performing model (Y∼MM/S:p<0.01, R=0.67). In conclusion, despite limitations in determining legal majority age, manubrium morphometry analysis presented statistically significant results for skeletal age estimation, which indicates that this bone structure may be considered as a new candidate in multi-factorial MRI-based age estimation.
基于骨骼结构的法医年龄估计研究聚焦于利用不同骨骼的生长和发育模式。在本研究中，我们的目的是使用磁共振成像（MRI）研究青少年和青年成人胸骨与生长相关的演变，MRI是一种不涉及电离辐射的图像采集方式。第一步，将个体胸骨和受试者特征与年龄进行关联，这证实了在所研究的年龄范围内，胸骨体积（M：p<0.01，R¯=0.50）和表面积（M：p<0.01，R¯=0.53）存在统计学上的显著变化。此外，首次使用主成分分析研究了胸骨的形状。数据在主成分中的分解使得能够分析每个成分对总形状变化的贡献。通过13个主成分，可以描述约96%的形状变化（M：p<0.01，R¯=0.60）。多元线性回归分析对统计学上相关性最佳的变量与年龄之间的关系进行了建模。包含胸骨形状、体积或表面积除以受试者身高的模型（Y∼MM/S：p<0.01，R¯=0.71；Y∼MM/S：p<0.01，R¯=0.72）的估计标准误差为两年。为了估计这两个基于胸骨的年龄估计模型的准确性进行了交叉验证实验，在留出的测试集上预测年龄。表现最佳的模型（Y∼MM/S：p<0.01，R=0.67）预测年龄与已知实际年龄的中位数绝对差为1.18岁。总之，尽管在确定法定成年年龄方面存在局限性，但胸骨形态测量分析在骨骼年龄估计方面呈现出统计学上的显著结果，这表明该骨骼结构可被视为基于MRI的多因素年龄估计中的一个新候选因素。
