= APLASTIC ANEMIA

Cause: idiopathic; ? sequelae of viral infection, medication, toxin, chemo- / radiation therapy

Path: normal marrow replaced by fat cells

MR:

• high signal intensity on T1WI
• low signal intensity on fat-suppressed T2WI
• Best seen in areas with high percentage of hematopoietic marrow: proximal femoral metaphyses, spine