Fetal facial bone growth: Post-mortem CT analysis

OBJECTIVE

To describe and model the normal growth of fetal facial bones and angles.

MATERIAL AND METHODS

A total of 118 fetal CT scans obtained at 19 to 41 weeks gestation after in utero fetal death or late miscarriage were analyzed. CT scan was followed by autopsy and pathological examination and only fetuses free from brain disease or abnormal craniofacial development were included. The measurements were taken using software for frontal, sagittal and 3D reconstruction from native axial sections. The optimal plane for bone analysis was chosen and the measurements made by multiplanar reconstruction.

RESULTS

There was a statistically significant increase (P<0.001) in all measurements regardless of gestational age (GA) except those of the mandibulo-fronto-maxillary angle (P=0.412), the naso-mandibulo-maxillary angle (P=0.828) and mandibular width (P=0.86). There was no significant difference according to fetal sex. Based on these results, the corresponding growth curves were created. The anteroposterior mandibular diameter (APD) was very strongly correlated with GA (R=0.926, P<0.001). The following equation: GA=(8.187×APD)+4.257 can be used to estimate GA with a confidence interval (CI) of±2.42. The same applies to maxillary width (MW) (R=0.922; P<0.001). The equation GA=(11.059×MW)+7.571 can be used to estimate GA with a CI of 2.17.

CONCLUSION

The growth of the mandible, maxilla, zygomatic bone and orbits was measured and the corresponding growth curves were established. Several measurements were strongly correlated with gestational age.

Morphometric Analysis of the Orbital Aperture in North Indian Population: A Retrospective Digital Forensic Study

Introduction:

The morphometric variations seen in the orbital aperture play a significant role in forensic anthropology, for determining the personal and gender identification, especially in case of mass disasters.

Aim:

The aim of the present study was to evaluate the orbital aperture dimensions along with interorbital distance as observed on posteroanterior (PA) cephalograms for personal and gender identification.

Materials and Methods:

The present retrospective study was conducted to evaluate the morphometric dimensions of orbital aperture seen on PA cephalogram taken using PLANMECA digital machine and ROMEXIS software. The height and width of the orbits along with the interorbital distance were measured using measuring tools in the accompanying software. Data were analyzed using SPSS software version 21.0.

Results:

All the linear measurements such as orbital height, orbital width, and interorbital distance were significantly greater in males than females in the North Indian population with P = 0.001. The present study found 84.8% accuracy after subjecting the obtained value to discriminant function analysis.

Conclusion:

The morphometric analysis of the orbital aperture using postero-anterior cephalogram can be used as an adjuvant for personal and gender identification in forensic anthropology.

Orbital aperture morphometry in Indian population: A digital radiographic study

Background:

Morphological variations of the orbital aperture measurements may be used in forensic medicine as a parameter for determining sexual and ethnic identity of an individual.

Aim and Objective:

The aim and objective of this study was to evaluate the orbital aperture dimensions in Indian individuals and verify their relationship with gender.

Materials and Methods:

A retrospective study was conducted using digital posteroanterior view radiographs of 50 males and 51 females, which were taken using NEWTOM GIANO-CEFLA SC machine (81 kVp, 10 mA, and 6.6 s). The orbital aperture measurements were carried out using NEWTOM software NNT version 5.5. The maximum width and height of the orbits and the inter-orbital distance were measured. The obtained data were subjected to t-test and discriminant function analysis.

Results:

In the t-test, significant differences in orbital width and inter-orbital distance were obtained between the genders. On subjecting the data to discriminant function analysis, result was obtained with 86.1% accuracy rate in gender determination.

Conclusion:

If the discriminant score is >1.0365, the skull is likely to be of a male, and if it is <1.0365, it is likely to be of a female. Therefore, orbital aperture measurements can be used for gender determination in human identification.

Virtual anthropology - a brief review of the literature and history of computed tomography

Computed tomography (CT) has influenced numerous fields since its inception in the 1970s. The field of palaeoanthropology significantly benefited from this efficient and non-invasive medium in terms of the conservation, reconstruction and analysis of fossil human remains. Over the past decade, there has been a steady increase in the number of forensic anthropological studies incorporating virtual osteological analyses. Because of the increasing importance of these modern cross-sectional imaging techniques and the requirement for standardized parameters in forensic science, we deemed it important to outline the history and development of CT applications in these related academic areas. The present paper outlines the history of “virtual anthropology” and osteological multi-detector CT in the context of palaeoanthropology and forensic anthropology.

Correlation between age and the parameters of medial epiphysis and metaphysis of the clavicle using CT volume rendering images

OBJECTIVES

The aim of this study was to evaluate the correlation between age and the parameters of medial epiphysis of clavicle based on CT volume rendering (VR) images.

MATERIALS AND METHODS

The CT images of the medial clavicle from 795 teenagers (387 male and 408 female) between 15 and 25 years were collected in East and South China. VR images were recombined from 0.60 mm thickness slice CT images. The ratio of epiphyseal diameter/metaphyseal diameter and the ratio of epiphyseal area/metaphyseal area of two sides of medial clavicle were measured and calculated by three different examiners, the quantitative data consistency was checked by intraclass correlation coefficients (ICC). The diameter ratio of left and right side are depicted as X1 and X3, and the area ratio of left and right side as X2 and X4. Descriptive statistic analysis of the data was performed and several mathematical models were established using least square. CT images from additional 60 teenagers (30 male and 30 female) were used to verify the accuracy of the established mathematical models.

RESULTS

ICC indicated that the measurement of epiphyseal diameter, metaphyseal diameter, the ratio of epiphyseal diameter/metaphyseal diameter, epiphyseal area, metaphyseal area and the ratio of epiphyseal area/metaphyseal area of medial clavicle in the left and right side of the three examiners was approaching 1. The 95% reference range for the mean of every examination of both genders gradually increased with age. Females' data indicated by medial epiphysis of the clavicle development were earlier than male's, especially from 15 to 21 years. The difference of medial epiphysis of the clavicle development in gender becomes smaller after 21 years. The highest accuracy of the mathematical models made clear that male's accuracy was 73.5% (±1.0 year) and 85.3% (±1.5 year), and female's was 68.6% (±1.0 year) and 82.2% (±1.5 year) respectively.

CONCLUSION

The methods of data collection and analysis were reliable and feasible. Combined the high accuracy of these established mathematical models, it is applicable to use the ratio of epiphyseal diameter/metaphyseal diameter and the ratio of epiphyseal area/metaphyseal area of left and right side of medial clavicle to estimate the teenager's age. Bearing this in mind, further studies are needed to evaluate slice thickness as the most critical parameter.

Ossification degrees of cranial sutures determined with flat-panel computed tomography: narrowing the age estimate with extrema

Since Broca's time (1824-1880), ossification of the neurocranial sutures has been used as a characteristic of age. Current approaches include the visual macroscopic examination of ecto and endocranial sutures. The evaluation of the cross-section of sutures usually necessitates the destruction of the neurocranium. In a nondestructive alternative approach that was tested within the context of the "Digital Forensic Osteology" project that ran in cooperation with the Virtopsy-Project, it emerged that the resolution of conventional multi-slice computed tomography data sets was not high enough to image sutures. Thus for the experiments presented here, the eXplore Locus Ultra flat-panel computed tomography scanner from GE Healthcare was used. Calottes were scanned during autopsy and then immediately returned to the corpse. So far, the skullcaps of 221 individuals have been scanned. The cross-sections of 14 suture segments could be assessed for seven previously defined stages of ossification. In a converse step, the 14 highest and lowest age estimate values corresponding to the individual stages of suture closure found were estimated for each calotte. The obtained ranges narrowing down the age estimate were evaluated with statistics. A mean value of 43.31 years for the range of narrowed age estimates shows that this method can be a useful aid in estimating age. The results of intra- and inter-observer tests showed good overall agreement between the findings of three observers. This method is suitable for a nondestructive age estimation and can be used for the entire calotte.