Obert Martin, Seyfried Maren, Schumacher Falk, Krombach Gabriele A, Verhoff Marcel A
Department of Neuroradiology, University Hospital Gießen, Justus-Liebig University Gießen, Klinikstraße 33, D-35392 Gießen, Germany.
Department of Neuroradiology, University Hospital Gießen, Justus-Liebig University Gießen, Klinikstraße 33, D-35392 Gießen, Germany.
Forensic Sci Int. 2014 Sep;242:24-31. doi: 10.1016/j.forsciint.2014.06.018. Epub 2014 Jun 26.
Aging human remains is a critical issue in anthropology and forensic medicine, and the search for accurate, new age-estimation methods is ongoing. In our study, we, therefore, explored a new approach to investigate a possible correlation between age-at-death (aad) and geometric irregularities in the bone structure of human skull caps. We applied the concept of fractal geometry and fractal dimension D analysis to describe heterogeneity within the bone structure.
A high-resolution flat-panel computed tomography scanner (eXplore Locus Ultra) was used to obtain 229,500 images from 221 male and 120 female (total 341) European human skulls. Automated image analysis software was developed to evaluate the fractal dimension D, using the mass radius method. The frontal and the occipital portions of the skull caps of adult females and males were investigated separately. The age dependence of the fractal dimension D was studied by correlation analysis, and the prediction accuracy of age-at-death (aad) estimates for individual observations was calculated.
D values for human skull caps scatter strongly as a function of age. We found sex-dependent correlation coefficients (CC) between D and age for adults (females CC=-0.67; males CC=-0.05). Prediction errors for aad estimates for individual observations were in the range of ±18 years at a 75% confidence interval.
The detailed quantitative description of age-dependent irregularities in the bone microarchitecture of skull vaults through fractal dimension analysis does not, as we had hoped, enable a new aging method. Severe scattering of the data leads to an estimation error that is too great for this method to be of practical relevance in aad estimates. Thus, we disclosed an interesting sex difference.
衰老人类遗骸是人类学和法医学中的一个关键问题，目前正在寻找准确的新型年龄估计方法。因此，在我们的研究中，我们探索了一种新方法，以研究死亡年龄（aad）与人类颅盖骨结构中的几何不规则性之间可能存在的相关性。我们应用分形几何概念和分形维数D分析来描述骨结构内的异质性。
使用高分辨率平板计算机断层扫描仪（eXplore Locus Ultra）从221例男性和120例女性（共341例）欧洲人类头骨中获取229,500张图像。开发了自动图像分析软件，使用质量半径法评估分形维数D。分别对成年女性和男性颅盖骨的额部和枕部进行了研究。通过相关性分析研究了分形维数D的年龄依赖性，并计算了个体观察的死亡年龄（aad）估计值的预测准确性。
人类颅盖骨的D值随年龄变化而强烈分散。我们发现成年人中D与年龄之间存在性别依赖性相关系数（CC）（女性CC = -0.67；男性CC = -0.05）。在75%置信区间内，个体观察的aad估计值的预测误差在±18岁范围内。
通过分形维数分析对颅顶骨微结构中与年龄相关的不规则性进行详细的定量描述，并没有如我们所希望的那样产生一种新的衰老方法。数据的严重分散导致估计误差过大，使得该方法在aad估计中没有实际意义。因此，我们揭示了一个有趣的性别差异。
