7 results on '"Lynnerup, Niels"'
Search Results
2. A Method for Estimating Age of Medieval Sub-Adults From Infancy to Adulthood Based on Long Bone Length.
- Author
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Primeau, Charlotte, Friis, Laila, Sejrsen, Birgitte, and Lynnerup, Niels
- Subjects
REGRESSION analysis ,RADIOGRAPHY ,RADIOLOGY ,SCIENTIFIC photography ,BRAIN - Abstract
Objectives: To develop a series of regression equations for estimating age from length of long bones for archaeological sub-adults when aging from dental development cannot be performed. Further, to compare derived ages when using these regression equations, and two other methods. Material and Methods: A total of 183 skeletal sub-adults from the Danish medieval period, were aged from radiographic images. Linear regression formulae were then produced for individual bones. Age was then estimated from the femur length using three different methods: equations developed in this study, data based on a modern population (Maresh: Human growth and development (1970) pp 155-200), and, lastly, based on archeological data with known ages (Rissech et al.: Forensic Sci Int 180 (2008) 1-9). As growth of long bones is known to be non-linear it was tested if the regression model could be improved by applying a quadratic model. Results: Comparison between estimated ages revealed that the modern data result in lower estimated ages when compared to the Danish regression equations. The estimated ages using the Danish regression equations and the regression equations developed by Rissech et al. (Forensic Sci Int 180 (2007) 1-9) were very similar, if not identical. This indicates that the growth between the two archaeological populations is not that dissimilar. Discussion: This would suggest that the regression equations developed in this study may potentially be applied to archaeological material outside Denmark as well as later than the medieval period, although this would require further testing. The quadratic equations are suggested to yield more accurate ages then using simply linear regression equations. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
3. The Danish approach to forensic age estimation in the living: how, how many and what’s new? A review of cases performed in 2012.
- Author
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Larsen, Sara Tangmose, Arge, Sara, and Lynnerup, Niels
- Subjects
SKELETAL maturity ,BONE growth ,AGE determination of human beings ,FORENSIC pathology ,DENTAL radiography ,BAYESIAN analysis - Abstract
Background: The resulting statement of forensic age estimations in the living is of great consequence for the examinees in question. Concerns have been raised about the nature of these examinations, e.g. the potentially harmful radiographic exposures, as well as the accuracy of the estimated age. Aim: This manuscript investigates the reported age estimates performed at the Section of Forensic Pathology, Institute of Forensic Medicine, Copenhagen, in 2012. Subjects and methods: The results of the individual assessments, i.e. the physical examination, and the radiographic examinations of bone age and dental age, were investigated as well as the correlation between the age estimates of the two latter examinations. Results: In 139 out of the 174 statements, a conclusive chronological age estimate of at least 18 years was given. Although bone age was assessed within the dental age-range in a total of 152 out of 162 cases, some variations in the combined assessments were seen. Conclusion: The current procedure is not mathematically or statistically satisfactory. Instead, the most likely age including the variation and error of the age estimate should be reported in statements. The introduction of a Bayesian approach and the use of post-mortem-imaging-based databases may be used for this purpose. [ABSTRACT FROM PUBLISHER]
- Published
- 2015
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- View/download PDF
4. The Use of CT Scans in Estimating Age at Death by Examining the Extent of Ectocranial Suture Closure.
- Author
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Boyd, Kristen Leigh, Villa, Chiara, and Lynnerup, Niels
- Subjects
FORENSIC sciences ,FORENSIC anthropology ,AGE determination of animals ,COMPUTED tomography ,CRANIAL sutures - Abstract
We examined the utility of CT scans in the evaluation of degree of ectocranial suture closure. Five cranial points (left and right midcoronal positions, left and right midlambdoidal positions, and the lambda) were evaluated in 231 CT scans using a three-point scoring system (open, partial closed, and closed). The slice increment and thickness varied between three groups of the scans. The results showed a good correlation between degree of suture closure and increasing age in each group. Young individuals (<40 years) and old individuals (>60 years) could be clearly distinguished from the middle-aged individuals. ANOVA test revealed no difference between two groups of scans and between left and right sides ( p > 0.05). Interobserver agreement was good, especially considering the score by sides. The results of this study create the base for developing a robust and simple method to estimate the age at death using CT scans. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
5. Technical Note: Reliability of suchey-brooks and buckberry-chamberlain methods on 3D visualizations from CT and laser scans.
- Author
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Villa, Chiara, Buckberry, Jo, Cattaneo, Cristina, and Lynnerup, Niels
- Subjects
TOMOGRAPHY ,PUBIC bone ,SURFACE texture ,VISUALIZATION ,MATHEMATICAL models ,PUBIC symphysis - Abstract
ABSTRACT Previous studies have reported that the ageing method of Suchey-Brooks (pubic bone) and some of the features applied by Lovejoy et al. and Buckberry-Chamberlain (auricular surface) can be confidently performed on 3D visualizations from CT-scans. In this study, seven observers applied the Suchey-Brooks and the Buckberry-Chamberlain methods on 3D visualizations based on CT-scans and, for the first time, on 3D visualizations from laser scans. We examined how the bone features can be evaluated on 3D visualizations and whether the different modalities (direct observations of bones, 3D visualization from CT-scan and from laser scans) are alike to different observers. We found the best inter-observer agreement for the bones versus 3D visualizations, with the highest values for the auricular surface. Between the 3D modalities, less variability was obtained for the 3D laser visualizations. Fair inter-observer agreement was obtained in the evaluation of the pubic bone in all modalities. In 3D visualizations of the auricular surfaces, transverse organization and apical changes could be evaluated, although with high inter-observer variability; micro-, macroporosity and surface texture were very difficult to score. In conclusion, these methods were developed for dry bones, where they perform best. The Suchey-Brooks method can be applied on 3D visualizations from CT or laser, but with less accuracy than on dry bone. The Buckberry-Chamberlain method should be modified before application on 3D visualizations. Future investigation should focus on a different approach and different features: 3D laser scans could be analyzed with mathematical approaches and sub-surface features should be explored on CT-scans. Am J Phys Anthropol 151:158-163, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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6. Forensic age estimation from the clavicle using 1.0 T MRI-Preliminary results.
- Author
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Tangmose, Sara, Jensen, Karl Erik, Villa, Chiara, and Lynnerup, Niels
- Subjects
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MAGNETIC resonance imaging , *OSSIFICATION , *CLAVICLE , *FORENSIC radiography , *AUTOPSY - Abstract
Objectives: As forensic age estimations in the living are performed without medical indication, there is a need for the development of non-ionizing methods. This study investigates the use of 1.0 T MRI to visualize the ossification status of the medial end of the clavicle. Material and methods: T2 weighted 3D images were collected from a 1.0 T MR system. We prospectively scanned 102 subjects, 47 autopsy cases and 55 living volunteers (12-33 years). Images were scored in blind trials by three observers using a 4-stage system. Observers differed by level of training and radiological expertise. Results: Motion artefacts reduced image resolution in living subjects. However, mean age at stage 4 was significantly different from mean age at stage 2 and 3. The minimum age at stage 4 was 19.8 years. Interobserver agreement was moderate for autopsy cases and slight for living subjects. By contrasting subjects of ''incomplete fusion'' (≤ stage 3 on both sides) against ''fused'' (at least one stage 4), agreement rate rose to moderate (K = 0.414) for living subjects. Despite the low agreement rate, no subject younger than 18 years was assessed as having ''fused'' clavicles. Conclusion: At lower image resolution, a 2-stage system increases agreements rates among observers. To further increase accuracy, clavicle staging needs to be performed by trained observers. If available, a 1.0 T MR system may be used for age estimation in the living. However, further studies are needed to ensure that the ability to discriminate adults from minors, i.e. 18 years, is maintained. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
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7. Forensic age estimation based on the trabecular bone changes of the pelvic bone using post-mortem CT.
- Author
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Villa, Chiara, Hansen, Maria Normand, Buckberry, Jo, Cattaneo, Cristina, and Lynnerup, Niels
- Subjects
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CANCELLOUS bone , *PUBIC bone , *ILIUM , *FORENSIC anthropology , *COMPUTED tomography , *X-ray imaging , *FEMUR - Abstract
We analyzed the trabecular bone changes in the pubic bone (PB) and in the auricular surface (AS) of the ilium using 319 CT scans of cadavers to estimate the age. Although the sharpness of the trabecular structure decreases in CT images when soft tissues are present, we identified four phases for the changes in PB and five in AS; a juvenile trait in PB and a senile trait in AS helped narrow the age range. High correlation with age was identified for both sexes in PB (F 0.89; M 0.75) and in AS (F 0.85; M 0.71) used independently or combined (F 0.91; M 0.78). The old adults (>60 years) could be evaluated with better accuracy and discriminated in several phases. We found low inter-observer error and low inaccuracy (about 6 years, mean for all age ranges). The method is robust with respect to slice thickness, display window and kernel within the tested ranges. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
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