The authors report, for the first time, sodium properties of human art
icular cartilage in vivo using sodium multiple-quantum-filtered method
s with a surface coil, A flip angle-independent, phase-cycled pulse se
quence was used to obtain triple-quantum-filtered spectra as a functio
n of preparation time, Biexponential relaxation rates were calculated
by fitting the triple-quantum-filtered spectral amplitudes to a theore
tical expression, Theoretical analysis of the flip angle dependence of
even rank two-quantum coherence (T-2(2)), Odd rank two-quantum cohere
nce (T-2(3)), and triple-quantum coherence are presented and verified
against experimental results on a cartilage specimen, Sodium multiple-
quantum-filtered spectral lineshapes obtained in vivo correlate well w
ith those observed on in vitro specimens, Relaxation rates obtained fr
om asymptomatic volunteers were found to be: T-2rise = 1.0 +/- 0.12 ms
, T-2decay = 12.0 +/- 0.75 ms (mean +/- SD), The diagnostic potential
of this method in detecting early changes in articular cartilage is de
scribed.