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Micro computed tomography (micro-CT) has already been proposed as a useful technique for the qualitative analysis of false starts (FS) produced on human bones, although the reliability and the error rate of this technique have not been tested yet, neither for qualitative nor for quantitative assessments. The aim of the present study was to test the morphological agreement, accuracy, precision and inter-rater reliability of micro-CT analysis of FS on bones. The morphological agreement was assessed through the degree of concordance among the 3 independent blind raters in the identification of the shape of 24 FS manually produced on bones by 3 different saws (8 FS for each saw). The accuracy was calculated through the percentage of error in the automatic and manual measurement of the diameter of a reference object. The precision was calculated as CV% of multiple measurements performed by 3 independent blind raters on the reference object and one bone sample acquired 20 times. The inter-rater reliability was assessed as intraclass correlation coefficient (ICC) among measurements performed by 3 independent blind raters, assessing 24 FS produced using 3 different saws. The results demonstrated that both qualitative and quantitative analysis were reproducible and robust. Micro-CT analysis showed a 100% morphological agreement, a high level of accuracy (percentage error < 0,5%), precision (CV% < 5%) and inter-rater reliability (ICC > 0.995), when FS were analyzed by forensic pathologists and/or radiologists with adequate expertise. Obviously, further validation studies are needed, including a higher number of samples produced by a wider variety of saws and multiple operators. [ABSTRACT FROM AUTHOR]

The analysis of macro- and microscopic characteristics of saw marks on bones can provide useful information about the class of the tool utilized to produce the injury. The aim of the present study was to test micro-computed tomography (micro-CT) for the analysis of false starts experimentally produced on 32 human bone sections using 4 different hand-saws in order to verify the potential utility of micro-CT for distinguishing false starts produced by different saws and to correlate the morphology of the tool with that of the bone mark. Each sample was analysed through stereomicroscopy and micro-CT. Stereomicroscopic analysis allowed the identification of the false starts and the detection of the number of tool marks left by each saw. Micro-CT scans, through the integration of 3D renders and multiplanar reconstructions (MPR), allowed the identification of the shape of each false start correlating it to the injuring tool. Our results suggest that micro-CT could be a useful technique for assessing false starts produced by different classes of saws, providing accurate morphological profiles of the bone marks with all the advantages of high resolution 3D imaging (e.g., high accuracy, non-destructive analysis, preservation and documentation of evidence). However, further studies are necessary to integrate qualitative data with quantitative metrical analysis in order to further characterize the false start and the related injuring tool. [ABSTRACT FROM AUTHOR]

Cases of subtle fatal neck compression are often complicated by the lack of specificity of the post-mortem signs of asphyxia and by the lack of clear signs of neck compression. Herein we present a forensic case of a 45-year-old schizophrenic patient found on the floor of the bedroom of a psychiatric ward in cardiopulmonary arrest and who died after two days in a vegetative state. The deposition of the roommate of the deceased, who claimed responsibility for the killing of the victim by neck compression, was considered unreliable by the prosecutor. Autopsy, toxicological analyses, and multi-slice computed tomography (MSCT), micro computed tomography (micro-CT) and histology of the larynx complex were performed. Particularly, micro-CT analysis of the thyroid cartilage revealed the bilateral presence of ossified triticeous cartilages and the complete fragmentation of the right superior horn of the thyroid, but it additionally demonstrated a fracture on the contralateral superior horns, which was not clearly diagnosable at MSCT. On the basis of the evidence of intracartilaginous laryngeal hemorrhages and bilateral microfracture at the base of the superior horns of the larynx, the death was classified as a case of asphyxia due to manual strangulation. Micro-CT was confirmed as a useful tool in cases of subtle fatal neck compression, for the detection of minute laryngeal cartilage fractures, especially in complex cases with equivocal findings on MSCT. [ABSTRACT FROM AUTHOR]