الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 127 |  |  |
| | | from | 127 | | |
Abstract
Skeletal bones have been widely used in sex estimation for the forensic and medicolegal purposes. Sex determination from the skeletal bones helps in the exclusion of 50% of individuals during the identification process.
There has been a growing trend toward the virtual autopsy ”virtopsy” in investigating the cause of death. Radiological imaging such as CT is a non-invasive method by which human identification can be done.
The presence and size of costal cartilages are positively correlated with advanced age in older persons. There is a significant level of sexual dimorphism in the human clavicle which makes these bones eligible for sex estimation, particularly, when the pelvic bones and skull are unavailable. The pelvis is the gold standard sex-identifier bone, followed by the skull, and other postcranial bones such as the clavicles.
The present study was conducted to assess the accuracy of the multi-detector computed tomography (MDCT) as a tool for age and sex determination from clavicles and costal cartilages.
It was done on 168 Egyptians (98 males and 70 females) from different age groups. The participants were randomly selected from cases referred to Radiodiagnosis department at Alexandria University Hospitals for radiological investigations by multi-detector computed tomography (MDCT) of the chest as part of their clinical workup after a consent from all the participants.
All measurements were measured in mm unit with an accuracy of 0.1 mm.
The following measurements and assessment were done:
1- Measurements for sex estimation from clavicles:
Measurements were taken from both sides.
• Maximum clavicular length (MCL).
• Anteroposterior midshaft clavicular diameter (APCD).
• Sternal Head Length (SHL).
• Sternal Epiphyseal width (SEW).
2- Sex estimation from costal cartilages:
Pattern of costal cartilage calcification according to McCormick’s classification and Rejtarova classification.
McCormick et al (1985) classified the calcification patterns into 8 categories (type A to H) while Rejtarova et al (2004) method divided their calcification patterns as the following: Type I was classified as male pattern while Type II was considered as a female pattern. Sex cannot be assessed in both Types III and IV.
3- Age estimation from clavicles:
• The assessment of morphological changes of the ossification status of the “medial clavicular epiphyseal cartilage” (MCE) using Schmeling’s five phases scoring system (stages (a) to (e)).
• The radio-density of the axial surface of the “sternal epiphyseal-metaphyseal region” (SEM).
4- Age estimation from costal cartilages:
• Radio-density of upper, middle, and lower thirds of the 1st costal cartilage was measured on CT axial sections by the ROI tool which quantified in Hounsfield units (HU).
• Age was determined from the “osseous and calcified projections” (OCPs) of the costal cartilages which were classified into 8 ossification stages (stages 1 to 8).
The present study revealed the following results:
1- Measurements for sex estimation from clavicles:
• All measurements showed an agreement in the intra-observe measurements by paired t-test and Pearson coefficient with no statistical differences.
• In MCL and SHL measurements, the right clavicles were significantly shorter than the left side regardless of sex.
• The APCD and SEW are , on average, statistically significantly larger on the right side.
• The male mean values were significantly (p < 0.001) larger than female values in right and left SHL, MCL, SEW, and APCD measurements.
• SHL measurements show significant differences between males and females in the age groups (20- < 30 yrs.) and (40- < 50 yrs.) in both sides.
• SEW measurements showed a statistically significant difference between males and females on both sides of the (40-< 50 yrs.) age while the (20- < 30 yrs.) and the (60- < 70 yrs.) age groups showed a statistical difference in the right clavicle only.
• MCL measurements revealed statistical differences between both sexes in both sides of the age groups (20- < 60) yrs., however, there was no statistical difference between males and females who were older than 60 years.
• APCD measurements showed a significant sexual dimorphism of both sides of the clavicle in the age groups (20- < 70) yrs.
• The most accurate variable was APCD of the right and left sides with an accuracy of 87% and 88.4%, respectively.
• The 2nd most accurate variable was MCL with an accuracy of 81.2 % and 84.7% for the right and left sides, correspondingly.
• The lowest accuracy was obtained from SEW of both right and left sides with an accuracy of 63.8%.
• The best performance of sex discrimination between males and females by ROC was achieved by APCD with AUC 0.923 of both sides of the clavicle. while those of the 2nd best sex-identifier (MCL) were 0.893 and 0.901 of the right and left sides, respectively .
• The least sensitive variable was SEW with AUC 0.680 and 0.664 of the right and left sides, correspondingly.