[Posttherapeutic changes in bone marrow]

The bone marrow basically consists of red blood-forming bone marrow and yellow fat. In the skeleton, there is an age-dependent distribution of these two parts. In the context of medical interventions or therapies, bone marrow changes can occur, whereby the normal bone marrow can basically be replaced by fat, edema, or fibrosis/sclerosis. Here, specific signal intensities and patterns are shown in imaging. After irradiation therapies, edematous changes, hemorrhages, and osteoradionecroses are observed. Likewise, insufficiency fractures, impairment of the growth gaps, or the development of tumors is possible. In patients on dialysis, deposit of protein in the bone marrow is possible in the case of the so-called amyloidosis osteoarthropathy. Postoperative bone marrow edema, insufficiency fractures, or osteonecrosis can be observed after arthroscopy. Changes in the distribution of fat markers and blood-forming bone marrow can be observed after stem cell transplants. In the therapy with cortisone, insufficiency fractures and osteonecroses are possible. Depending on their effect on the hematopoietic system, chemotherapyies can first lead to edematous changes and then to fatty bone marrow, which is reversible after therapy. Angiogenesis inhibitors in combination with other chemotherapeutic agents often lead to mixed images of stimulated and fatty bone marrow.