Traumatic Brain Injury: A Forensic Approach: A Literature Review

Abstract

Traumatic brain injury (TBI) is the principal cause of invalidity and death in the population under 45 years of age worldwide. This mini-review aims to systematize the forensic approach in neuropathological studies, highlighting the proper elements to be noted during external, radiological, autoptical, and histological examinations with particular attention paid to immunohistochemistry and molecular biology. In the light of the results of this mini-review, an accurate forensic approach can be considered mandatory in the examination of suspected TBI with medico-legal importance, in order to gather all the possible evidence to corroborate the diagnosis of a lesion that may have caused, or contributed to, death. From this point of view, only the use of an evidence-based protocol can reach a suitable diagnosis, especially in those cases in which there are other neuropathological conditions (ischemia, neurodegeneration, neuro-inflammation, dementia) that may have played a role in death. This is even more relevant when corpses, in an advanced state of decomposition, are studied, where the radiological, macroscopic and histological analyses fail to give meaningful answers. In these cases, immune-histochemical and molecular biology diagnostics are of fundamental importance and a forensic neuropathologist has to know them. Particularly, MiRNAs are promising biomarkers for TBI both for brain damage identification and for medico-legal aspects, even if further investigations are required to validate the first experimental studies. In the same way, the genetic substrate should be examined during any forensic examination, considering its importance in the outcome of TBI.

Keywords: Traumatic brain injury; autoptic approach; forensic radiology; histopathology; miRNA; molecular biology; neuropathology..

Fig. (1)

Radiological approach. A. Angio CT-Premortem: extensive hypodensity in the subcortical areas of the left frontal lobe. Extensive hypodensity affects the cortico-subcortical regions of the parietal, occipital and cerebellar lobes, of probable ischemic meaning, bilaterally. The angio-CT study documented a complete occlusion of both vertebral arteries from their origin, where they appear threadlike, up to the C3 vertebral body. From this level, they appeared reperfused, even if the right one seems to be reduced in size and less opacified than the left one. No modifications were detected on the basilar trunk. B. CT-Postmortem: a large hypodense area in the parietal and frontal lobes, bilaterally, of probable infarct origin; parietal calcifications of the carotid axes at the level of bifurcation and of the siphons; parietal calcifications of the right vertebral artery. Dislocation of C5 from C4 with large dehiscence of the disc space and associated thickening of paravertebral tissues. (A higher resolution / colour version of this figure is available in the electronic copy of the article).

Fig. (2)

Posterior approach during autopsy. A. C4-vertebra dislocated from the C5-vertebra with posterior exposure of the spinal cord and hemorrhagic dural sac. B. After the transverse processes had been sectioned, the course of the vertebral arteries into the transverse foramen was visualized. C. The anatomical preparation composed of the brain and the spinal cord up to the upper border of the C5-vertebra. (A higher resolution / colour version of this figure is available in the electronic copy of the article).

Fig. (3)

This flow chart summarizes the multidisciplinary forensic approach in TBI. (A higher resolution / colour version of this figure is available in the electronic copy of the article).