Forensic age estimation with ankle MRI: Evaluating distal tibial and calcaneal epiphyseal fusion

Forensic authorities often request age estimation from forensic experts, particularly in cases related to sexual abuse, child pornography, illegal migration, marriage, etc. The most commonly used method in this regard is radiological methods. Because of the potential dangers of radiation exposure outside of clinical indications, new researches are focusing on non-ionizing and non-invasive technologies. This study aimed to demonstrate the applicability of age estimation in living individuals from ankle magnetic resonance images as a non-ionizing method, and to determine whether it is compatible with individuals' real ages and to establish a database. Ankle MRI images of patients aged between 7 and 26 years who applied to the Cukurova University Faculty of Medicine Balcali Hospital between January 2011 and December 2020 were retrospectively evaluated. A six-stage staging method proposed by Lu et al. was applied to the distal tibial and calcaneal epiphyseal ossification points by examining ankle MRI images of a total of 331 patients, 197 males and 134 females. In the study, images obtained from a sagittal section fast spin echo T1-weighted sequence, with a section thickness of 3-4 mm, were evaluated. As a result of the study, Stage 1 in both distal tibial and calcaneal epiphysis was observed only in patients under 18 years of age in both sex. In males, stage 2 in distal tibial epiphyseal ossification was observed under 18 years of age, except for one case, and stage 5 in both distal tibial and calcaneal epiphyseal ossification was observed in almost all cases over 18 years of age in males. According to the results of our study, magnetic resonance imaging was found to be a non-ionizing method that could be used in addition to other radiological methods aimed at determining the 18-year age limit in age estimation. Multicenter, comparative, and prospective studies conducted by experienced researchers are needed to enable the routine use of MRI in age estimation.