Apparent focal bone marrow ischemia in patients with marrow disorders: MR studies.

OBJECTIVE: We sought to assess with MR the focal bone marrow abnormalities in patients with chronic marrow disorders and acute limb pain. MATERIALS AND METHODS: We investigated and followed with MRI four patients with proliferative or dysplastic marrow disorders presenting with acute but spontaneously resolving hip or thigh pain. RESULTS: Ten focal marrow lesions were demonstrated on T2-weighted images as high signal intensity (SI) areas. They remained undetected on T1-weighted images as they showed a low SI similar to the disease-related low SI of the entire marrow. Postcontrast images demonstrated lack of enhancement in the lesions. Follow-up enhanced MR images showed intense enhancement within the lesions, while unenhanced MR images remained unchanged. Later on, these focal marrow abnormalities completely resolved. These lesions most likely represent bone marrow ischemia, although histological proof is lacking. CONCLUSION: Acute bone pain in patients with bone marrow disorders may be related to focal marrow lesions suggestive of bone marrow ischemia.