[Magnetic resonance aspects of the bone marrow in aplastic anemia at the onset and in the follow-up after transplant].

Aplastic anemia is a rare hematologic disorder characterized by hypocellular fatty marrow. Aplastic anemia is diagnosed on the basis of laboratory tests and bone marrow biopsy findings. Biopsy is of fundamental importance for bone marrow assessment, though not representative of the rest of the marrow. Thanks to its exclusive capabilities in the direct visualization of bone marrow, MRI is a noninvasive and relatively rapid method for bone marrow study. The authors report their experience in 3 aplastic anemia patients examined also with MRI at presentation and after marrow transplantation. The dorsolumbar spine was studied with sagittal SE T1-weighted and STIR sequences, while pelvic bones were investigated only with SE T1-weighted sequences in all patients. Two of them were also examined with sagittal scans of the dorsolumbar spine using the chemical shift fat suppression technique. In all three patients, SE T1-weighted images at presentation showed fatty bone marrow infiltration, also confirmed on fat suppression images, and, after transplantation, progressive bone marrow repopulation, with the typical "band" pattern in vertebral marrow. Although MR specificity remains low in the demonstration of bone marrow disorders, the authors believe it to be a useful tool, after accurate clinical and laboratory exams, not only in the diagnosis but also and especially in the follow-up of these disorders.