title: Trabecular bone volume fraction measurements of a large number of subjects using a compact MRI.
abstract: Trabecular bone volume fraction (TBVF) and speed of sound (SOS) were measured for the right calcanei of 416 female volunteers. The TBVF was measured with a compact MRI developed in our laboratory. The SOS was measured with a commercial quantitative ultrasound system. It was observed that the correlation coefficient between TBVF and SOS and that between TBVF and age varied depending on the location of region of interest (ROI) in the calcaneus. As a result, an optimum circular ROI with a diameter of 20 mm was determined so that the correlation coefficients were maximized. In the optimum ROI, transverse relaxation time (T2) of the bone marrow protons of the calcaneus was found to be concentrated in a narrow range over the subjects. This result suggested that a 50% scan time reduction in the TBVF measurements could be made by skipping the T2 correction procedure.
authors.affiliation: Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
authors.forename: Sadanori
authors.initials: S
authors.lastname: Tomiha
authors.forename: Nachiko
authors.initials: N
authors.lastname: Iita
authors.forename: Fumi
authors.initials: F
authors.lastname: Okada
authors.forename: Takeshi
authors.initials: T
authors.lastname: Furuya
authors.forename: Katsumi
authors.initials: K
authors.lastname: Kose
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Haishi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015519:Bone Density; D002111:Calcaneus / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D008875:Middle Aged; D015203:Reproducibility of Results