Osteogenesis imperfecta is an inherited disease characterized by increased bone fragility with recurrent fractures that can lead to skeletal deformities. OI patients have normal bone density at DEXA, but bone structure is highly deteriorated in the whole skeletal system.
A group led by Dr. Heinrich Resch, professor of medicine at the Medical University of Vienna, and colleagues at Vienna's Krankenhaus der Barmherzigen Schwestern examined 15 patients (12 women, 3 men; mean age, 42 years), comparing them with a demographically similar group of healthy men and women. The analysis was performed using an HR-pQCT scanner and several micro-CT scanners, and results were correlated with DEXA measurements.
"Bone mineral density measurements ... do not allow estimation of the structure pattern, which is the pathognomonic substrate in this disease," Resch explained to AuntMinnie.com. The presence of severe skeletal deformities also complicates the performance of conventional bone mineral density scans in these patients, who are mostly postmenopausal women, he said.
With its high spatial resolution of 82 µm and a low radiation exposure of 3 µSv effective dose per 9-mm slice, HR-pQCT offers significant additional information about bone architecture in osteoporosis and fracture risk, the researchers found. They found significant differences between HR-pQCT and DEXA in several measures, including trabecular bone volume to tissue volume, trabecular separation, and inhomogeneity of network-derived architectural parameters of the radius and tibia hip between patients with OI and healthy individuals.
"The different structural parameters obtained by HR-pQCT seem to reflect the highly deteriorated architecture in peripheral bone, making the measurements superior to other imaging modalities in displaying the anatomy and architecture of bones and in diagnosing structural abnormalities with higher confidence," Resch said, adding that the promising data appear to make investment in the technology worthwhile.
