Predicting osteomyelitis in patients whose initial MRI demonstrated bone marrow edema without corresponding T1 signal marrow replacement

摘要

Purpose We endeavored to determine which characteristics of diabetic ulcers portend the strongest risk for osteomyelitis in patients whose initial T1-weighted imaging was normal. By determining which features have a greater risk for osteomyelitis, clinicians can treat patients more aggressively to reduce the sequela of inadequately treated osteomyelitis. Materials and methods We performed a retrospective analysis of MR imaging from 60 pedal ulcers with suspected osteomyelitis. Ulcer dimensions and depth were measured. Ratios of marrow ROI/joint fluid ROI on T2/STIR sequences were obtained. Progression to osteomyelitis on subsequent MRI was characterized by loss of normal marrow signal on T1-weighted images. Statistical analysis was performed with a two-samplettest and Cox proportional hazard model. Apvalue 53% had a 6.5-fold increased risk of osteomyelitis,p < 0.001. Proximity to bone averaged 6 mm in the osteomyelitis group and 9 mm in the non-osteomyelitis group,p = 0.02. Ulcer size averaged 4 cm(2)in the osteomyelitis group versus 2.4 cm(2)in the non-osteomyelitis group,p = 0.07. Ulcers greater than 3 cm(2)has a 2-fold increase in the risk of osteomyelitis,p = 0.04. Conclusion Increasing bone marrow ROI signal/joint fluid ratios on T2/STIR images were the strongest risk factors for developing osteomyelitis, while ulcer size and depth are weaker predictors.