The iron stores can be evaluated using the Prussian blue stain. Abnormal iron granules can be detected in erythroid cells. PAGE 6 Aspirate selects for normal elements which are easily sucked out through a small needle, but abnormal elements such as tumour metastases may be retained. The marrow biopsy offers certain advantages over aspiration. The two techniques complement each other, and thus, the decision whether to perform aspiration or biopsy, or both, should be based on the specific information required.
Marrow is quite uniform and subject to little sampling error.
Assessment of the In Vitro Growth Characteristics Assessment of the in vitro growth characteristics of the haemopoietic precursors and the humoral modulators of differentiation has provided a wealth of knowledge about pathophysiology, but is seldom needed in clinical medicine, except when assessing haemopoietic progenitor cells in marrow harvested for bone marrow transplantation. Assays for EPO Assays for EPO have limited application in the investigation of erythrocytosis.