How The Test Is Performed
A bone marrow biopsy may be done in a health care provider's office or in a hospital. Informed consent for the procedure is typically required. The patient is asked to lie on his or her abdomen (prone position) or on his/her side (lateral decubitus position). The skin is cleansed, and a local anesthetic such as lidocaine or procaine is injected to numb the area. Patients may also be pretreated with analgesics and/or anti-anxiety medications, although this is not a routine practice.
Typically, the aspirate is performed first. An aspirate needle is inserted through the skin using manual pressure and force until it abuts the bone. Then, with a twisting motion of clinician's hand and wrist, the needle is advanced through the bony cortex (the hard outer layer of the bone) and into the marrow cavity. Once the needle is in the marrow cavity, a syringe is attached and used to aspirate ("suck out") liquid bone marrow. A twisting motion is performed during the aspiration to avoid excess content of blood in the sample, which might be the case if an excessively large sample from one single point is taken.
Subsequently, the biopsy is performed if indicated. A different, larger trephine needle is inserted and anchored in the bony cortex. The needle is then advanced with a twisting motion and rotated to obtain a solid piece of bone marrow. This piece is then removed along with the needle. The entire procedure, once preparation is complete, typically takes 10–15 minutes.
If several samples are taken, the needle is removed between the samples to avoid blood coagulation.
In 2010, a power system was offered for sale. Previously, needles were forced through the bone manually, which required significant upper-body strength and effort by the person performing the procedure. The power system, made of a specially designed needle and a powered driver similar to a power drill, produced comparable or better core sample quality in tests. It was also much faster and easier.
Read more about this topic: Bone Marrow Examination
Famous quotes containing the words test and/or performed:
“Utopias are presented for our inspection as a critique of the human state. If they are to be treated as anything but trivial exercises of the imagination. I suggest there is a simple test we can apply.... We must forget the whole paraphernalia of social description, demonstration, expostulation, approbation, condemnation. We have to say to ourselves, “How would I myself live in this proposed society? How long would it be before I went stark staring mad?””
—William Golding (b. 1911)
“We are responsible for actions performed in response to circumstances for which we are not responsible.”
—Allan Massie (b. 1938)