Bone Marrow Patterns
Diagnosis | Findings | Comments |
Normal variation in residual red marrow and/or vascular channels | Foci of decreased T1- and increased T2-weighted signal intensity distributed throughout fatty marrow. | The pattern typically seen at the hands and feet usually resolves around 15 y of age, although various patterns may also be seen in adults.56,57 |
Rebound or stimulated hematopoietic marrow | Foci of decreased T1- and increased T2-weighted signal intensity distributed throughout fatty marrow. | After initiation of hematopoietic stimulating therapy or on cessation of therapies toxic to red marrow. |
Chronic repetitive trauma | Presumably from trabecular microfractures. | |
Juvenile rheumatoid arthritis Fig. 5.106, p. 567 | Foci of bone marrow edema adjacent to joints seen on MRI. | Bone marrow edema (osteitis) has been correlated with future erosions.58 |
Reflex sympathetic dystrophy | Bone marrow edema tends to be larger, more focal, and confluent. | Often accompanied by osteopenia and soft-tissue atrophy in the appropriate clinical setting. |
AVN Fig. 5.173a, b, p. 614 Fig. 5.174, p. 614 Fig. 5.175, p. 614 | Early: occult on radiographs with diffuse bone marrow edema on MRI and increased activity on bone scan. Middisease: alternating serpiginous bands of alternating low and high signal intensity on MRI ± characteristic findings of osteonecrosis on radiography.21 | |
Transient osteoporosis | Radiographs may show bone demineralization. | |
Osteoid osteoma and osteoblastoma | Intense bone marrow edema on MRI. | The bone marrow edema tends to extend well beyond the nidus. |
Metastatic disease Fig. 5.132, p. 586 Fig. 5.136, p. 589 | More confluent edema ± soft-tissue mass or bone destruction. |
Diagnosis | Findings | Comments |
Overproduction of hematopoietic marrow | Diffusely decreased T1- and increased T2-weighted marrow signal intensity on MRI. | DD: sickle cell disease, thalassemia, and other hemoglobinopathies. |
Hematologic malignancy | MRI marrow changes may be accompanied by lucent metaphyseal bands on radiographs. | |
Inflammation | Diffusely decreased T1- and increased T2-weighted marrow signal intensity on MRI may be accompanied by periosteal reaction. | |
Infection | Similar findings as with inflammation. | |
Rebound following bone marrow stem cell transplantation |
Diagnosis | Findings | Comments |
Apophysitis | Increased fluid signal intensity in the apophysis ± increased fluid signal intensity in the synchondrosis. | Common locations: patella (bipartite patella), ankle (os trigonum), shoulder (os acromiale). |
Avulsion | Large gap in the expected location of the synchondrosis suggests avulsion. | |
Pseudofracture | Synchondrosis may simulate a fracture. | Bipartite patella. |