R. Grunder et al., Visualization of pressure distribution within loaded joint cartilage by application of angle-sensitive NMR microscopy, MAGN RES M, 43(6), 2000, pp. 884-891
Citations number
13
Categorie Soggetti
Radiology ,Nuclear Medicine & Imaging","Medical Research Diagnosis & Treatment
High-resolution MRI measurements on knee joints show a multilaminar appeara
nce of the cartilage. This intracartilaginar structure, visualized as hypoi
ntense zones in T-2-weighted MR images is based on the dipolar interaction
of water molecules within regions of anisotropic arrangement of collagen ne
twork. Using the different angle dependence of the MR signal, tones of radi
ally and tangentially oriented network structures can be distinguished. Inf
ormation equivalent to that from polarization light microscopy can be deriv
ed noninvasively, This is demonstrated by polarization light microscopic re
ference investigations, It is shown that this multilaminar MRI appearance i
s sensitively influenced by mechanical stress. A model explaining the contr
ary behavior of loaded tangential and radial network structures is given. B
ased on this pressure dependence, a noninvasive determination of mechanical
properties is possible. Using the variation of size and intensity of the h
ypointense zones under pressure, dynamic high resolution MRI yields noninva
sive information about the intracartilaginar pressure distribution similar
to photoelastic measurements. Magn Reson Med 43:884-891, 2000. (C) 2000 Wil
ey-Liss, Inc.