How does the MRI appearance of acute osteomyelitis differ if the source of infection is hematogenous? Many of the ancillary signs that are typically used to establish the diagnosis of acute osteomyelitis will be absent—in particular, a skin ulcer is unlikely to be present. Infection may present only as patchy areas of bone marrow edema. …
What are the routes of spread of infection that involve bone? Osteomyelitis is most commonly caused by (1) direct spread from adjacent tissues, particularly through a skin ulcer, but can also be introduced by (2) penetrating trauma, (3) surgical contamination, or (4) hematogenous seeding.
What can help establish the diagnosis of acute osteomyelitis on MRI? First, clinical history that is suggestive of infection is useful to make a diagnosis of acute osteomyelitis. Additionally, other findings of infection often are encountered, including skin ulceration, cellulitis, fasciitis, pyomyositis, phlegmon, and abscess. The presence of such findings increases confidence that the bone …
What can help establish the diagnosis of acute osteomyelitis on MRI Read More »
What are the MRI findings of osteomyelitis? On MRI, acute osteomyelitis manifests as bone marrow edema with increased signal intensity on fluid-sensitive sequences such as T2-weighted and short tau inversion recovery (STIR) images with corresponding decreased signal intensity on T1-weighted images. The same findings which may be visible radiographically (cortical destruction and periosteal reaction) are …
Is bone marrow edema specific for the diagnosis of acute osteomyelitis? No. Bone marrow edema may be caused by many other processes including traumatic injury, stress reaction, postsurgical change, tumors, and so forth.
Is there a role for MRI if radiographs are positive for acute osteomyelitis? MRI is often unnecessary for the diagnosis of osteomyelitis if this has already been established radiographically. However, MRI excels in delineating the extent of the infection and is often helpful in preoperative planning.
Is there a role for MRI if radiographs are negative for acute osteomyelitis? Yes, particularly if there is suspicion for early or low-grade osteomyelitis.