bone marrow aspiration

Bone marrow examination refers to the pathologic analysis of samples of bone marrow obtained by bone marrow biopsy (often called a trephine biopsy) and bone marrow aspiration. Bone marrow examination is used in the diagnosis of a number of conditions, including leukemia, multiple myeloma, anemia, and pancytopenia. The bone marrow produces the cellular elements of the blood, including platelets, red blood cells and white blood cells. While much information can be gleaned by testing the blood itself (drawn from a vein by phlebotomy), it is sometimes necessary to examine the source of the blood cells in the bone marrow to obtain more information on hematopoiesis; this is the role of bone marrow aspiration and biopsy.
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Bone marrow n. The soft, fatty, vascular tissue filling the cavities of bones, having a stroma of reticular fibers and cells. [more]Bone marrow aspiration - Community and Resources

The removal of a small sample of bone marrow (usually from the hip) through a needle for examination under a microscope to see whether cancer cells are present.

[as-per-AY-shun]
The removal of a small sample of bone marrow (usually from the hip) through a needle for examination under a microscope.