Fw. Wehrli et al., CANCELLOUS BONE VOLUME AND STRUCTURE IN THE FOREARM - NONINVASIVE ASSESSMENT WITH MR MICROIMAGING AND IMAGE-PROCESSING, Radiology, 206(2), 1998, pp. 347-357
PURPOSE: To develop and apply a method for the derivation of cancellou
s bone architectural parameters from in vivo magnetic resonance (MR) i
mages of the distal radius and to evaluate these parameters as predict
ors of vertebral fracture status in osteopenia. MATERIALS AND METHODS:
MR images (137 x 137 x 500-mu m(3) voxel size) were acquired with a t
hree-dimensional partial flip-angle spin-echo pulse sequence in the di
stal radius of 36 women. Subjects were classified as healthy or with o
steoporosis on the basis of vertebral deformity and bone mineral densi
ty (BMD). Images rated as of adequate quality in 20 subjects were proc
essed with a method that is applicable in the limited spatial resoluti
on regime. The method relies on histogram deconvolution to Obviate bin
ary segmentation. Cancellous bone structure was treated as a quasi-reg
ular lattice and analyzed with spatial autocorrelation, yielding param
eters that quantify intertrabecular spacing, contiguity, and a measure
of longitudinal alignment called tubularity. RESULTS: Whereas neither
BMD nor any of the structural parameters individually correlated sign
ificantly with vertebral deformity fraction, a simple function that in
volved tubularity and longitudinal spacing predicted deformity fractio
n well (r = .78, P < .005). CONCLUSION: Histomorphometric parameters c
haracterizing cancellous bone in the distal radius can be derived from
in vivo MR microimages and are predictive of vertebral deformity.