In vivo triple quantum filtered twisted projection sodium MRI of human articular cartilage

In this work, we present the first triple quantum filtered (TQF) sodium MR images of the human knee joint in vivo. A 3D TQF data set of 16 slices was obtained in 20 min using a TQF pulse sequence preencoded to a twisted proje ction imaging readout. Images clearly demarcate patellar cartilage and also demonstrate fluid signal suppressed by the triple quantum filter. Biexpone ntial transverse relaxation times were calculated by fitting the TQF free i nduction decay to a theoretical signal expression. The average values from three healthy volunteers were T*(2fall) = 9.59 +/- 0.35 ms and T*(rise) = 0 .84 +/- 0.06 ms. Application of TQF imaging in biological tissues is discus sed, (C) 1999 Academic Press.