Bone marrow is the soft tissue inside bones that helps form blood cells. It is found in the hollow part of most bones. Bone marrow aspiration is the removal of a small amount of this tissue in liquid form for examination.
Bone marrow aspiration is not the same as bone marrow biopsy . A biopsy removes actual marrow for examination.
How the Test is Performed
Bone marrow aspiration may be done in the health care provider’s office or in a hospital. The bone marrow is removed from your pelvic or breast bone. Sometimes, another bone is selected.
Marrow is removed in the following steps:
- If needed, you are given medicine to help you relax.
- The provider cleans the skin and injects numbing medicine into the area and surface of the bone.
- A special needle is inserted into the bone. The needle has a tube attached to it, which creates suction. A small sample of bone marrow fluid flows into the tube.
- The needle is removed.
- Pressure and then a bandage are applied to the skin.
The bone marrow fluid is sent to a laboratory and examined under a microscope.
How to Prepare for the Test
Tell the provider:
- If you are allergic to any medicines
- If you are pregnant
- If you have bleeding problems
- What medicines you are taking
How the Test will Feel
You will feel a sting and slight burning sensation when the numbing medicine is applied. You may feel pressure as the needle is inserted into the bone, and a sharp and usually painful sucking sensation as the marrow is removed. This feeling lasts for only a few seconds.
Why the Test is Performed
Your doctor may order this test if you have abnormal types or numbers of red or white blood cells or platelets on a complete blood count.
This test is used to diagnose:
- Anemia (some types)
- Infections
- Leukemia
- Other blood cancers and disorders
It may help determine whether cancers have spread or responded to treatment.
Normal Results
The bone marrow should contain the proper number and types of:
- Blood-forming cells
- Connective tissues
- Fat cells
What Abnormal Results Mean
Abnormal results may be due to cancers of the bone marrow, including:
- Acute lymphocytic leukemia (ALL)
- Acute myelogenous leukemia (AML)
- Chronic lymphocytic leukemia (CLL)
- Chronic myelogenous leukemia (CML)
Abnormal results may also be due to other causes, such as:
- Bone marrow doesn’t make enough blood cells (aplastic anemia)
- Bacterial or fungal infections that have spread throughout the body
- Cancer of the lymph tissue (Hodgkin or non-Hodgkin lymphoma )
- A bleeding disorder called idiopathic thrombocytopenic purpura (ITP)
- Blood cancer called ( multiple myeloma )
- Disorder in which the bone marrow is replaced by scar tissue ( myelofibrosis )
- Disorder in which not enough healthy blood cells are made (myelodysplastic syndrome; MDS)
- Abnormally low amount of platelets, which help blood to clot (primary thrombocytopenia )
- White blood cell cancer called Waldenström macroglobulinemia
Risks
There may be some bleeding at the puncture site. More serious risks, such as serious bleeding or infection, are very rare.
