Bauer Melanie, Deigendesch Nikolaus, Wittig Holger, Scheurer Eva, Lenz Claudia
Institute of Forensic Medicine, Department of Biomedical Engineering, University of Basel, Basel, Switzerland; Institute of Forensic Medicine, Health Department Basel-Stadt, Basel, Switzerland.
Institute of Medical Genetics and Pathology, University Hospital Basel, University of Basel, Basel, Switzerland.
Forensic Sci Int. 2021 Apr 29;323:110808. doi: 10.1016/j.forsciint.2021.110808.
The post mortem evaluation of a brain edema is routinely performed by pathologists based on the macroscopic signs during autopsy. This method represents the current gold standard, but is subjective and observer dependent. Therefore, three post mortem evaluation methods of brain samples were analyzed in this work: histology, wet-dry weight and normalized cerebral weight, which was described in 2020 by Bauer et al. Tissue samples from six different regions of 34 brains were collected and examined both by rating of histological slides and by measuring the water content by using a drying oven. The rating of the histological slides, stained with hematoxylin and eosin, was performed by two pathologists independently. For the water content, the wet weight and the dry weight of each sample were set in relation. The normalized cerebral weight was calculated by dividing the brain weight by the brain volume, which were both determined during autopsy and in computed tomography images, respectively. A fair to moderate interrater agreement was obtained for the histologic evaluation and a significant correlation was present between one rater and the wet-dry weight and the normalized cerebral weight method. When classifying according to the gold standard, a significant difference was detected between the edematous and nonedematous cases by using the wet-dry weight method in the cerebral cortex and by using the normalized cerebral weight method. However, the significant correlations and group differences were limited to the aforementioned results. In conclusion, both the histological and the wet-dry weight method show limited benefits for the classification of brain edema and the histology analysis is highly observer dependent. The normalized cerebral weight method, however, reveals a significant effect between the edematous and nonedematous cases when classifying according to the gold standard. Therefore, we suggest to apply this method for the assessment of brain edema since it is objective and rater independent. Nevertheless, the exact evaluation of brain edema remains a challenging task, especially due to the continuous transition between no edema and edema.
病理学家通常在尸检时根据宏观体征对脑水肿进行死后评估。这种方法是目前的金标准，但具有主观性且依赖观察者。因此，本研究分析了三种脑样本的死后评估方法：组织学、湿重-干重法和标准化脑重法，后者由鲍尔等人于2020年描述。收集了34个大脑六个不同区域的组织样本，并通过组织学切片评分和使用干燥箱测量含水量进行检查。两名病理学家独立对苏木精和伊红染色的组织学切片进行评分。对于含水量，将每个样本的湿重和干重进行关联。标准化脑重通过将脑重除以脑体积来计算，脑重和脑体积分别在尸检和计算机断层扫描图像中确定。组织学评估获得了中等程度的评分者间一致性，一名评分者与湿重-干重法和标准化脑重法之间存在显著相关性。根据金标准进行分类时，在大脑皮质中使用湿重-干重法以及使用标准化脑重法时，水肿病例和非水肿病例之间检测到显著差异。然而，显著相关性和组间差异仅限于上述结果。总之，组织学和湿重-干重法在脑水肿分类方面益处有限，且组织学分析高度依赖观察者。然而，根据金标准进行分类时，标准化脑重法在水肿病例和非水肿病例之间显示出显著差异。因此，我们建议应用这种方法评估脑水肿，因为它客观且不依赖评分者。尽管如此，脑水肿的准确评估仍然是一项具有挑战性的任务，特别是由于无水肿和水肿之间的连续过渡。
