Περίληψη:
Purpose: To assess the performance and results of R2 relaxometry using a fat-suppressed (FS) multiecho sequence and compare these to conventional R2 relaxometry in estimating tissue iron overload. Materials and Methods: Relaxation rate values (R2=1/T2) of the liver, spleen, pancreas and vertebral bone marrow (VBM) were estimated in 21 patients with β-thalassemia major, using a respiratory-triggered 16-echo Carr-Purcell-Meiboom-Gill (CPMG) spin-echo sequence before (R2) and after (R2 FS) the application of chemically selective fat suppression. Results: Hepatic and splenic R2 FS values correlated with respective R2 values (r=0.98 and r=0.96, P<.001), whereas correlations between R2 FS and R2 values for pancreas and VBM were not statistically significant. Bland-Altman plots show disagreement between R2 and R2 FS values, particularly for pancreas and VBM. Hepatic, pancreatic and VBM R2 FS values correlated with serum ferritin (r=0.88, P<.001; r=0.51, P<.003; and r=0.75, P<.002, respectively). Hepatic R2 FS values correlated with splenic R2 FS (r=0.77, P<.03), pancreatic R2 FS (r=0.61, P<.006) and VBM R2 FS values (r=0.70, P<.001), whereas pancreatic R2 FS values correlated also with VMB R2 FS values. On the contrary, among the R2 values of the above tissues, obtained without fat suppression, only hepatic R2 values correlated with serum ferritin, whereas no correlation was documented between hepatic and pancreatic or VBM R2 values. The application of fat suppression did not improve breathing or flow artifacts. Conclusion: Application of fat suppression in the standard CPMG sequence improved the capability of MRI in noninvasive quantification of iron, particularly in lipid-rich tissues, such as vertebral bone marrow (VBM) and pancreas. © 2012 Elsevier Inc.
Συγγραφείς:
Papakonstantinou, O.
Foufa, K.
Benekos, O.
Alexopoulou, E.
Mademli, M.
Balanika, A.
Economopoulos, N.
Kelekis, N.L.
Λέξεις-κλειδιά:
deferiprone; deferoxamine; ferritin; iron; lipid, adolescent; adult; article; artifact; beta thalassemia; bone marrow; bone marrow hemosiderosis; breathing mechanics; child; clinical article; correlation analysis; erythrocyte transfusion; fat suppression; female; ferritin blood level; hemosiderosis; human; image analysis; iron chelation; iron overload; liver; liver hemosiderosis; male; measurement; non invasive measurement; nuclear magnetic resonance imaging; pancreas; pancreas hemosiderosis; priority journal; quantitative analysis; radiological parameters; relaxometry; school child; spleen; spleen hemosiderosis; splenectomy; statistical significance; vertebra, Adolescent; Adult; beta-Thalassemia; Child; Female; Humans; Intra-Abdominal Fat; Iron; Iron Overload; Magnetic Resonance Imaging; Male; Reproducibility of Results; Sensitivity and Specificity; Tissue Distribution; Young Adult