- What is bone marrow?
- What is a bone marrow procedure (aspiration and/or biopsy)?
- What types of doctors perform bone marrow aspirates and/or bone marrow biopsies?
- Why are bone marrow biopsies or aspirations done?
- What bone is used to sample the bone marrow?
- How is a bone marrow aspiration and/or biopsy performed?
- What is done with the bone marrow sample?
- What diseases are diagnosed by bone marrow examination?
- What are the risks or complications of a bone marrow procedure?
How is a bone marrow aspiration and/or biopsy performed?
Typically, only a local anesthetic is required to numb the skin and tissue down to the surface of the bone. A small cut (less than ¼ inch) is then made in the skin. A hollow needle whose center is filled by a removable metal rod (called a trochar) is used to penetrate through the dense outer shell of bone. This needle (the most popular is termed the Jamshidi needle) can be used for both aspiration of marrow liquid or for a needle biopsy core of solid material. Once inside the bone, the trochar is removed and a syringe is attached to the now hollow tube of the bone marrow needle. The bone marrow is withdrawn as a thick liquid by pulling back on the plunger of the syringe and collecting the liquid. This sample is known as the marrow aspirate. This part of the procedure only lasts a few seconds but is usually the most painful due to the sudden sense of a negative pressure inside the bone.
A biopsy can also then be obtained in addition to the marrow aspirate or when an aspirate cannot be obtained. The same needle is used but without the center portion in place. As the needle is partially rotated into the bone, it cuts a core that is trapped inside the needle. Once the needle is removed, this core can be extracted from the needle barrel. This core can then be prepared with fixatives and stains for examination under a microscope.
Since the skin cut for both bone marrow procedures is usually very small, no stitches are generally necessary and only a bandage is applied. Recovery from the procedures is usually rapid (about one day, although some patients may feel tenderness at the site for about a week). Any post-procedure bleeding should be addressed by your physician. Those patients who require IV sedation will require someone to bring them home and should remain fairly sedentary for about 24 hours.
The cost of a bone marrow aspiration and/or biopsy varies greatly; it depends on the location (hospital or doctor's office), insurance coverage, and the country. Consequently, the cost range is wide (from about several hundred dollars to several thousand dollars) and may or may not include additional testing of the sample.
What is done with the bone marrow sample?
The bone marrow core biopsy is first placed in a liquid that keeps the cells in their natural condition (fixative solution). The sample is then placed in a solution to soften the bone and is finally processed like other biopsies in the tissue study (histology) laboratory. The liquid portion of the bone marrow is spread on glass slides and stained to make the bone marrow smears. The slides are then examined under the microscope, usually by a specially qualified technician followed by a physician such as a hematologist or pathologist. The results of aspiration or bone marrow biopsy are examined for abnormal appearing cells, reduced amount of normal bone marrow cells as compared to normal marrow values, and the presence or absence of cancer cells as well as other abnormal structures. Portions of either sample may be submitted to the microbiology laboratory for cultures. Certain conditions may require other specialized studies such as genetic testing or cell marker studies.