Jena University Hospital - Friedrich Schiller University Jena, Institute of Forensic Medicine, Am Klinikum 1, 07747, Jena, Germany.
Zuse Institute Berlin, Takustraße 7, 14195, Berlin, Germany.
Int J Legal Med. 2023 Nov;137(6):1815-1837. doi: 10.1007/s00414-023-03040-y. Epub 2023 Jun 19.
Rectal temperature measurement (RTM) from crime scenes is an important parameter for temperature-based time of death estimation (TDE). Various influential variables exist in TDE methods like the uncertainty in thermal and environmental parameters. Although RTM depends in particular on the location of measurement position, this relationship has never been investigated separately. The presented study fills this gap using Finite Element (FE) simulations of body cooling. A manually meshed coarse human FE model and an FE geometry model developed from the CT scan of a male corpse are used for TDE sensitivity analysis. The coarse model is considered with and without a support structure of moist soil. As there is no clear definition of ideal rectal temperature measurement location for TDE, possible variations in RTM location (RTML) are considered based on anatomy and forensic practice. The maximum variation of TDE caused by RTML changes is investigated via FE simulation. Moreover, the influence of ambient temperature, of FE model change and of the models positioning on a wet soil underground are also discussed. As a general outcome, we notice that maximum TDE deviations of up to ca. 2-3 h due to RTML deviations have to be expected. The direction of maximum influence of RTML change on TDE generally was on the line caudal to cranial.
直肠温度测量（RTM）来自犯罪现场是基于温度的死亡时间估计（TDE）的重要参数。TDE 方法存在各种有影响的变量，如热和环境参数的不确定性。虽然 RTM 特别取决于测量位置的位置，但这种关系从未单独进行过调查。本研究使用身体冷却的有限元（FE）模拟填补了这一空白。手动网格的粗人体 FE 模型和从男性尸体 CT 扫描开发的 FE 几何模型用于 TDE 灵敏度分析。考虑了带有和不带有湿土支撑结构的粗模型。由于 TDE 没有明确定义理想的直肠温度测量位置，因此根据解剖学和法医学实践考虑了 RTM 位置（RTML）的可能变化。通过 FE 模拟研究了由 RTML 变化引起的 TDE 最大变化。此外，还讨论了环境温度、FE 模型变化以及模型在湿地下的定位对 TDE 的影响。一般来说，我们注意到，由于 RTML 偏差，TDE 的最大偏差可能高达约 2-3 小时。RTML 变化对 TDE 的最大影响方向通常在颅尾线上。
