Papers by Nicolene Lottering
Forensic Science International, 2017
This study introduces a standardized protocol for conducting linear measurements of postcranial s... more This study introduces a standardized protocol for conducting linear measurements of postcranial skeletal elements using three-dimensional (3D) models constructed from post-mortem computed tomography (PMCT) scans. Using femoral DICOM datasets, reference planes were generated and plane-to-plane measurements were conducted on 3D surface rendered models. Bicondylar length, epicondylar breadth, anterior-posterior (AP) diameter, medial-lateral (ML) diameter and cortical area at the midshaft were measured by four observers to test the measurement error variance and observer agreement of the protocol (n = 6). Intra-observer error resulted in a mean relative technical error of measurement (%TEM) of 0.11 and an intraclass correlation coefficient (ICC) of 0.999 (CI = 0.998–1.000); inter-observer error resulted in a mean %TEM of 0.54 and ICC of 0.996 (CI = 0.979–1.000) for bicondylar length. Epicondylar breadth, AP diameter, ML diameter and cortical area also yielded minimal error. Precision testing demonstrated that the approach is highly repeatable and is recommended for implementation in anthropological investigation and research. This study exploits the benefits of virtual anthropology, introducing an innovative, standardized alternative to dry bone osteometric measurements.
Physiologic closure time of the metopic suture in South Australian infants from 3D CT scans
Metopic synostosis is a craniofacial condition characterised by the premature fusion of the metop... more Metopic synostosis is a craniofacial condition characterised by the premature fusion of the metopic suture. This early fusion restricts frontal bone growth [17] and has significant impacts on the developing infant during a critical phase of rapid growth and development [4]. Diagnosis of the condition is usually achieved by clinical assessment, followed by a three-dimensional computed tomography (3D CT) scan, verifying premature metopic suture fusion. Purpose This retrospective study aims to investigate the timing of metopic suture fusion in the developing infant in an Australian subpopulation. Methods The study evaluates metopic suture fusion in 258 cranial 3D CT scans of children aged 0–24 months over a 5-year period (2011–2016), scanned at Women’s and Children’s Hospital. Results The findings suggest that the age range over which physiologic metopic suture fusion occurs is larger than previously reported. Conclusions The approximate range for physiologic fusion was found to be 3–19 months and patients with fusion within this range can be considered normal. Complete suture fusion is expected by 19 months. Additionally, results indicate suture fusion prior to 3 months is abnormal and diagnostically indicative of metopic synostosis.
Author response to: Brough et al. in response to the recently published article: Lottering, N., MacGregor, D.M., Barry, M.D., Reynolds, M.S., Gregory, L.S., 2014. Introducing standardized protocols for anthropological measurement of virtual sub-adult crania using computed tomography 2(1), 34–38 Journal of Forensic Radiology and Imaging, 2014
Gregory, L.S., 2014. Introducing standardized protocols for anthropological measurement of virtua... more Gregory, L.S., 2014. Introducing standardized protocols for anthropological measurement of virtual sub-adult crania using computed tomography 2(1), 34-38
Contemporary, population-specific ossification timings of the cranium are lacking in current lite... more Contemporary, population-specific ossification timings of the cranium are lacking in current literature due to challenges in obtaining large repositories of documented subadult material, forcing Australian practitioners to rely on North American, arguably antiquated reference standards for age estimation. This study assessed the temporal pattern of ossification of the cranium and provides recalibrated probabilistic information for age estimation of modern Australian children. Fusion status of the occipital and frontal bones, atlas, and axis was scored using a modified two- to four-tier system from cranial/cervical DICOM datasets of 585 children aged birth to 10 years. Transition analysis was applied to elucidate maximum-likelihood estimates between consecutive fusion stages, in conjunction with Bayesian statistics to calculate credible intervals for age estimation. Results demonstrate significant sex differences in skeletal maturation (p < 0.05) and earlier timings in comparison with major literary sources, underscoring the requisite of updated standards for age estimation of modern individuals.
Due to disparity regarding the age at which skeletal maturation of the spheno-occipital synchondr... more Due to disparity regarding the age at which skeletal maturation of the spheno-occipital synchondrosis occurs in forensic and biological literature, this study provides recalibrated multi-slice computed tomography (MSCT) age standards for the Australian (Queensland) population, using a Bayesian statistical approach. The sample comprises retrospective cranial/cervical MSCT scans obtained from 448 males and 416 females aged birth to 20 years from the Skeletal Biology and Forensic Anthropology Research Osteological Database. Fusion status of the synchondrosis was scored using a modified six-stage scoring tier on an MSCT platform, with negligible observer error (κ = 0.911 ± 0.04, ICC = 0.994). Bayesian transition analysis indicates that females are most likely to transition to complete fusion at 13.1 years and males at 15.6 years. Posterior densities were derived for each morphological stage, with complete fusion of the synchondrosis attained in all Queensland males over 16.3 years of age and females aged 13.8 years and older. The results demonstrate significant sexual dimorphism in synchondrosis fusion and are suggestive of intra-population variation between major geographic regions in Australia. This study contributes to the growing repository of contemporary anthropological standards calibrated for the Queensland milieu to improve the efficacy of the coronial process for medico-legal death investigation. As a stand-alone age indicator, the basicranial synchondrosis may be consulted as an exclusion criterion when determining the age of majority that constitutes 17 years in Queensland forensic practice.
Objectives: This study introduces and assesses the precision of a standardized protocol for anthr... more Objectives: This study introduces and assesses the precision of a standardized protocol for anthropometric measurement of the juvenile cranium using three-dimensional surface rendered models, for implementation in forensic investigation or paleodemographic research.
Materials and Methods: A subset of multi-slice computed tomography (MSCT) DICOM datasets (n=10) of modern Australian subadults (birth – 10 years) was accessed from the “Skeletal Biology and Forensic Anthropology Virtual Osteological Database” (n>1200), obtained from retrospective clinical scans taken at Brisbane children hospitals (2009 – 2013). The capabilities of Geomagic Design XTM form the basis of this study; introducing standardized protocols using triangle surface mesh models to (i) ascertain linear dimensions using reference plane networks and (ii) calculate the area of complex regions of interest on the cranium.
Results: The protocols described in this paper demonstrate high levels of repeatability between five observers of varying anatomical expertise and software experience. Intra- and inter-observer error was indiscernible with total technical error of measurement (TEM) values ≤ 0.56mm, constituting < 0.33% relative error (rTEM) for linear measurements; and a TEM value of ≤ 12.89mm2, equating to < 1.18% (rTEM) of the total area of the anterior fontanelle and contiguous sutures.
Conclusions: Exploiting the advances of MSCT in routine clinical assessment, this paper assesses the application of this virtual approach to acquire highly reproducible morphometric data in a non-invasive manner for human identification and population studies in growth and development. The protocols and precision testing presented are imperative for the advancement of “virtual anthropology” into routine Australian medico-legal death investigation.
Forensic Science International , Jan 10, 2014
Despite the prominent use of the pubic symphysis for age estimation in forensic anthropology, lit... more Despite the prominent use of the pubic symphysis for age estimation in forensic anthropology, little has been documented regarding the quantitative morphological and micro-architectural changes of this surface. Specifically, utilising post-mortem computed tomography data from a large, contemporary Australian adult population, this study aimed to evaluate sexual dimorphism in the morphology and bone composition of the symphyseal surface; and temporal characterisation of the pubic symphysis in individuals of advancing age.
The sample consisted of multi-slice computed tomography (MSCT) scans of the pubic symphysis (slice thickness: 0.5 mm, overlap: 0.1 mm) of 200 individuals of Caucasian ancestry aged 15–70 years, obtained in 2011. Surface rendering reconstruction of the symphyseal surface was conducted in OsiriX1 (v.4.1) and quantitative analyses in Rapidform XOS and OsteomeasureTM. Morphometric variables including inter-pubic distance, surface area, circumference, maximum height and width of the symphyseal surface and micro-architectural assessment of cortical and trabecular bone compositions were quantified using novel automated engineering software capabilities.
The major results of this study are correlated with the macroscopic ossification and degeneration pattern of the symphyseal surface, demonstrating significant age-related changes in the morphometric and bone tissue variables between 15 and 70 years. Regardless of sex, the overall dimensions of the symphyseal surface increased with age, coupled with a decrease in bone mass in the trabecular and cortical bone compartments. Significant differences between the ventral, dorsal and medial cortical surfaces were observed, which may be correlated to bone formation activity dependent on muscle activity and ligamentous attachments. Our study demonstrates significant sexual dimorphism at this site, with males exhibiting greater surface dimensions than females. These baseline results provide a detailed insight into the changes in the structure of the pubic symphysis with ageing and sexually dimorphic features associated with the cortical and trabecular bone profiles.
Am J Phys Anthropol, Jan 3, 2013
Despite the prominent use of the Suchey–Brooks (S–B) method of age estimation in forensic anthrop... more Despite the prominent use of the Suchey–Brooks (S–B) method of age estimation in forensic anthropological practice, it is subject to intrinsic limitations, with reports of differential interpopulation error rates between geographical locations. This study assessed the accuracy of the S–B method to a contemporary adult population in Queensland, Australia and provides robust age parameters calibrated for our population. Three-dimensional surface reconstructions were generated from computed tomography scans of the pubic symphysis of male and female Caucasian individuals aged 15–70 years (n =195) in Amira and Rapidform. Error was analyzed on the basis of bias, inaccuracy and percentage correct classification for left and right symphyseal surfaces. Application of transition analysis and Chi-square statistics demonstrated 63.9 and 69.7% correct age classification associated with the left symphyseal surface of Australian males and females, respectively, using the S–B method. Using Bayesian statistics, probability density distributions for each S–B phase were calculated, providing refined age parameters for our population. Mean inaccuracies of 6.77 (62.76) and 8.28 (64.41) years were reported for the left surfaces of males and females, respectively; with positive biases for younger individuals (<55 years) and negative biases in older individuals. Significant sexual dimorphism in the application of the S–B method was observed; and asymmetry in phase classification of the pubic symphysis was a frequent phenomenon. These results recommend that the S–B method should be applied with caution in medico-legal death investigations of Queensland skeletal remains and warrant further investigation of reliable age estimation techniques.
Gregory, L.S., 2014. Introducing standardized protocols for anthropological measurement of virtua... more Gregory, L.S., 2014. Introducing standardized protocols for anthropological measurement of virtual sub-adult crania using computed tomography 2(1), 34-38
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Papers by Nicolene Lottering
Materials and Methods: A subset of multi-slice computed tomography (MSCT) DICOM datasets (n=10) of modern Australian subadults (birth – 10 years) was accessed from the “Skeletal Biology and Forensic Anthropology Virtual Osteological Database” (n>1200), obtained from retrospective clinical scans taken at Brisbane children hospitals (2009 – 2013). The capabilities of Geomagic Design XTM form the basis of this study; introducing standardized protocols using triangle surface mesh models to (i) ascertain linear dimensions using reference plane networks and (ii) calculate the area of complex regions of interest on the cranium.
Results: The protocols described in this paper demonstrate high levels of repeatability between five observers of varying anatomical expertise and software experience. Intra- and inter-observer error was indiscernible with total technical error of measurement (TEM) values ≤ 0.56mm, constituting < 0.33% relative error (rTEM) for linear measurements; and a TEM value of ≤ 12.89mm2, equating to < 1.18% (rTEM) of the total area of the anterior fontanelle and contiguous sutures.
Conclusions: Exploiting the advances of MSCT in routine clinical assessment, this paper assesses the application of this virtual approach to acquire highly reproducible morphometric data in a non-invasive manner for human identification and population studies in growth and development. The protocols and precision testing presented are imperative for the advancement of “virtual anthropology” into routine Australian medico-legal death investigation.
The sample consisted of multi-slice computed tomography (MSCT) scans of the pubic symphysis (slice thickness: 0.5 mm, overlap: 0.1 mm) of 200 individuals of Caucasian ancestry aged 15–70 years, obtained in 2011. Surface rendering reconstruction of the symphyseal surface was conducted in OsiriX1 (v.4.1) and quantitative analyses in Rapidform XOS and OsteomeasureTM. Morphometric variables including inter-pubic distance, surface area, circumference, maximum height and width of the symphyseal surface and micro-architectural assessment of cortical and trabecular bone compositions were quantified using novel automated engineering software capabilities.
The major results of this study are correlated with the macroscopic ossification and degeneration pattern of the symphyseal surface, demonstrating significant age-related changes in the morphometric and bone tissue variables between 15 and 70 years. Regardless of sex, the overall dimensions of the symphyseal surface increased with age, coupled with a decrease in bone mass in the trabecular and cortical bone compartments. Significant differences between the ventral, dorsal and medial cortical surfaces were observed, which may be correlated to bone formation activity dependent on muscle activity and ligamentous attachments. Our study demonstrates significant sexual dimorphism at this site, with males exhibiting greater surface dimensions than females. These baseline results provide a detailed insight into the changes in the structure of the pubic symphysis with ageing and sexually dimorphic features associated with the cortical and trabecular bone profiles.