Radiology, Vol 196, 631-641, Copyright © 1995 by Radiological Society of North America
Osteoporosis: clinical assessment with quantitative MR imaging in diagnosis
FW Wehrli, JC Ford and JG Haddad
Department of Radiology, University of Pennsylvania Medical Center, Philadelphia 19104, USA.
PURPOSE: To determine if the magnetic resonance (MR) imaging effective
transverse relaxation rate (R2*) of trabecular bone marrow is lowered in
osteoporosis. MATERIALS AND METHODS: R2* was measured in 146 women. Control
subjects (n = 77; mean age, 46.6 years) had high mean spinal bone mineral
densities (BMDs) and no vertebral deformities. Patients with spinal
osteoporosis (n = 59; mean age, 59.7 years) had at least one thoracic
vertebral deformity and/or low BMDs. RESULTS: R2* was lower in patients for
L-2 through L-5 (P < .001). Average R2* of L-3 through L-5 (R2*av) was
the best discriminator (64.79 sec-1 +/- 1.18 [standard error] for control
subjects vs 53.39 sec-1 +/- 1.24 for patients; P < .0001). R2*av
decreased with age in control subjects. The difference in R2*av in a subset
of 38 age-matched pairs of patients and control subjects was 8.25 sec-1 (P
< .0001). Subjects with deformities had lower 52*av than did control
subjects (52.3 sec-1 +/- 1.6 vs 62.5 sec-1 +/- 1.1, P < .0001). R2*av
was correlated with mean BMD (r = .54, P < .0001). CONCLUSION: Patients
with osteoporosis have lower R2*s in vertebral marrow.
