4 research outputs found
Repeatability of facial soft tissue thickness measurements for forensic facial reconstruction using X-ray images
The repeatability of facial soft tissue thickness measurements at 10 standard
anatomical landmarks was evaluated using lateral X-ray images obtained from 50
adult subjects. The intra-and inter-observer error rates were calculated after four
practitioners took measurements using Denta Pacs 8.1 software. The results indicated
high inter- and intra-observer repeatability, suggesting X-ray images can be
used to measure facial soft tissue thicknesses for the purpose of craniofacial
reconstruction and superimposition
Facing the past– In vivo facial soft tissue depths of a modern adult population from Germany
Forensic facial reconstruction may be the final option available to
draw the public attention in cases where the identity of an individual cannot
be established by standard identification methods. Two fundamental
components of all forensic facial reconstruction techniques are cranial
morphology and soft tissue depths databases. The purpose of this study was
to extend such databases by providing a complete set of accurate facial soft
tissue thickness measurements, acquired from a contemporary adult
population from Germany, for use in forensic facial reconstruction. The aims
were to measure the distance between well-defined landmarks on the skull
and reference points on the face in a standardised manner, to analyse how
sex, age and body mass index (BMI) influence facial soft tissue depths, to
identify patterns of facial asymmetry, and to conduct a comparative analysis
with other populations.
The material for this study consisted of 320 (160 male, 160 female)
anonymised multi-slice computerised tomography (MSCT) scans of
individuals drawn from a German population. Individuals between the ages
of 18 and 84 years were analysed. Their statures varied between 1.50 m and
1.96 m; their weights ranged between 40 kg and 145 kg. The BMI fluctuated
between 16.6 kg/m2 and 45.8 kg/m2. Patients with severe trauma or
pathologies that may compromise facial soft tissue depth were excluded
from the study as were patients known to have been treated with specific
medication (e.g. cortisone).
In Amira®, 3D models of the surfaces of the skull and the facial skin
were semi-automatically segmented using previously calculated thresholds
and surface extraction algorithms. The parameters were adjusted to permit
semi-transparent visualisation and examination of the structures of both the
3D skull and facial skin surface models simultaneously. Facial soft tissue
depth was measured at 10 midline and 28 bilateral anatomical landmarks,
according to the main orientations of the skull. Statistical analyses and tests
were performed with SPSS® Version 22 and TDStats Version v2015.1.
The analysis of facial soft tissue thickness versus BMI, sex and age, for
each landmark separately, indicated that, at a number of the landmarks,
facial soft tissue depth is significantly (p < 0.05) influenced by all three
biometric variables. Facial soft tissue thickness increased with increasing
BMI, but the correlations with age were insignificant. The differences
between males and females were statistically significant (p < 0.05) for almost
all anatomical landmarks with the exception of a few in the region of the
nasal root and orbitals. Asymmetry was noted at over half of the bilateral
landmarks.
The differences between the results from this sample and those
obtained from comparable databases contradict the hypothesis that
population-specificity significantly influences facial soft tissue thickness.
Nevertheless, this and future studies of craniofacial soft tissues will improve
our knowledge of the complexity of the human face. The information
gathered will be invaluable when considering forensic facial reconstruction
methods for neighbouring populations