[Proton MR spectroscopy of hyperplastic hematopoietic marrow in aplastic anemia]

The purpose of this study was to compare the findings of magnetic resonance (MR) spectroscopy of hyperplastic hematopoietic marrow with those of normal bone marrow. Twenty-four samples of normal marrow from eight control subjects and 19 samples of hyperplastic marrow in aplastic anemia were examined with a 1.5T MR unit. The former showed low intensity on opposed-phase T1-weighted images, while the latter showed high intensity on both fast STIR and opposed-phase T1-weighted images. MR spectroscopy quantitatively confirmed that the water: fat ratio was increased and the transverse relaxation time of water was changed in hyperplastic bone marrow, compared with normal bone marrow. In summary, MR imaging is able to detect hematopoietic regions among a wide range of bone marrow of aplastic anemia, while MR spectroscopy allowed us to quantitatively analyze the cell population of hyperplastic hematopoietic marrow in aplastic anemia.