[Quantification of signal modulation of hematopoietic bone marrow in gradient echo sequences. Results of phantom and proband studies with simultaneous determination of T2* relaxation times].
The signals from spongy bone on gradient echo sequences depend on the fat and water proton content as well as the differences in magnetic susceptibility at the border between the trabeculae and the bone marrow. From the signal intensities for different echo times, signal modulation was quantified by a special algorithm and at the same time the T2 relaxation time was calculated. Using a fat-water phantom, it was shown that the product of the initial fat and water signal intensity (modulation coefficient) is applicable to indicate the extent of signal modulation and thereby the chemical shift and, moreover, to indicate changes in the fat/water ratio sensitively. In 16 individuals of different ages (23 to 64 years, average 42.4 years) there was a tendency for the T2 relaxation time from the spongiosa of lumbar vertebrae to increase with age, this can be explained by a reduction in the trabecular content, causing reduction in the magnetic inhomogeneity of the bone marrow. The results indicate the usefulness of the sequence and the mathematical model for evaluating the spongy bone in cases of osteoporosis and of malignant haematological disorders.
Hidajat
N
N
Strahlenklinik und Poliklinik, Universitätsklinikum Rudolf Virchow, Freie Universität Berlin.
Hosten
N
N
Sander
B
B
Felix
R
R
D000328:Adult; D000367:Age Factors; D001853:Bone Marrow / Q000033:anatomy & histology* / Q000473:pathology; D001854:Bone Marrow Cells; D001855:Bone Marrow Diseases / Q000175:diagnosis; D005069:Evaluation Studies as Topic; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D008961:Models, Structural; D008962:Models, Theoretical; D010024:Osteoporosis / Q000175:diagnosis
Quantifizierung der Signalmodulation des blutbildenden Knochenmarkes in Gradienten-Echo-Sequenzen. Ergebnisse von Untersuchungen am Phantom und an Probanden mit gleichzeitiger Bestimmung der T2-Relaxationszeit.