Accurate interpretation of bone marrow aspirate specimens is highly dependent on two factors:
- The quality of the sample obtained by the clinician
- The quality of the prepared bone marrow smears
While the technologists have no control over the quality of the aspirate obtained by the clinician, in most cases they are able to impact the quality of laboratory prepared smears.
The method used for preparing slides may be dependent on sample volume, staining techniques, storage space, clinical setting, patient status, and hematopathologist's preference. Bone marrow sample preparations can be made on slides or coverslips from a direct marrow sample or a sample that is manipulated to enhance cellularity (selected for marrow fragments or spicules). In situations where the technologist goes to the bedside, touch-preparation (touch-prep) smears from the biopsy core can be prepared before it is placed in fixative.
Regardless of which method is the preferred primary technique at your institution, it is useful to be familiar with other methods, since there may be a situation when the use of an alternate method is the only way to obtain an interpretable smear.
When adequate samples are provided, it is desirable to make several slides or coverslips so that there will be enough preps available for all the possible tests/special stains that may be requested. The extra smears can be stored at room temperature and protected from light in an envelope or sleeve for further testing, if required.