Bone mineral density prediction using MRI

• Main Author: Lee, Tat Kian.
• Other Authors: Chou Siaw Meng
• Format: Final Year Project
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Mechanical engineering::Bio-mechatronics; DRNTU::Engineering::Mechanical engineering::Mechanics and dynamics
• Online Access: http://hdl.handle.net/10356/54190
• Institution: Nanyang Technological University

The main aim of this project was to find out the relationship between mechanical properties of bones with imaging parameters such as magnetic resonance imaging (MRI), micro computed tomography (μCT) and bone mineral density (BMD). This is to determine the possibility of MRI to predict BMD and mechanical properties of bone, and as an alternative to current invasive techniques for predicting osteoporosis. Firstly, cylindrical bone samples with aspect ratio 2:1, diameter of about 6 mm and height 12 mm were cored from distal femur of goat bone. Their masses were then measured before defatting. The bone samples then underwent μCT and MRI scans to determine their structural parameters. These include bone volume fraction (BVF), trabecular thickness (Tb.Th), trabecular number (Tb.N) and trabecular spacing (Tb.Sp). The bone samples were then scanned using dual energy x-ray absorptiometry (DXA) to obtain their BMD values. The mechanical test was done after all the scans to obtain mechanical properties such as elastic modulus and ultimate stress. Mechanical properties were then correlated with BMD, μCT, MRI parameters and apparent density. The CT parameters were used as a basis for comparison. The validity of BMD for this investigation was also done to determine its accuracy, and the optimum BMD scan area was evaluated to be 0.09 cm2. Data obtained from this investigation was also compared with previous work to discuss any discrepancy in values from the mechanical properties in current investigation. The data were also combined to compare the relationship between dry and wet specimens in previous studies, and then used to correlate with BMD, CT and MRI parameters. All μCT parameters were found to be significantly correlated with the mechanical properties and BMD, except Tb.Th. Correlation values between MRI parameters with BMD and mechanical properties remain generally low, except for the case for BVF. Hence, it can be concluded that MRI at current resolution can only serve as an aid in deducing osteoporosis accurately, but unable to replace DXA completely.