Volumetric and Microscopic Pattern of Bone Marrow in Normal Infants and Children

In normal infants 3 months of age or younger, particles obtained from the bone marrow by the described aspiration technic may be comprised of 80% or more hemopoietic tissue. Particles obtained by aspirations of the sternum and iliac crest from normal individuals 19 months through 11 years of age may vary from 35 to 80% hemopoietic tissue. Aspirations from the tibia of normal individuals 4½ years of age or older may contain 20% or less hemopoietic tissue. No lymph follicles were found in serial sections of particles from 23 normal individuals 3 days through 11 years of age.