Eliana Anna Fatone MD, Presenter: Nothing to Disclose

Jacquelyn Copeland MD, Abstract Co-Author: Nothing to Disclose

Massimo Savastano, Abstract Co-Author: Nothing to Disclose

Javier Beltran MD, Abstract Co-Author: Nothing to Disclose

To retrospectively review the bone marrow signal abnormalities and associate soft tissue findings of MRI of patients with diabetic foot performed for clinically suspected osteomyelitis and compare the results with bone biopsy (considered as gold standard).

Using a computer search all patients who had an MRI of the foot between January 2009 and February 2011 were identified. From this group those with a history of diabetes, suspected osteomyelitis and a bone biopsy were selected and retrospectively reviewed. All MRI images were reviewed to assess the presence of signs of osteomyelitis (concordant high signal on fluid sensitive sequences and low signal on T1 images, cortical irregularity or disruption),associated soft tissue abnormalities (ulcers, sinus tracts, callus, fluid collections, muscle atrophy) and other pathologies typical of the diabetic foot. The MRI results were compared with those of the bone biopsy in detecting osteomyelitis. The mean time interval between the MR and biopsy was 10±3 days.  

A total of 52 patients were included in our study (29 patients had an MRI without contrast and 23 patients before and after administration of contrast). In 40 patients both MR images and bone biopsy confirmed the presence of osteomyelitis at the site of clinical suspicion (true positive). In 4 cases osteomyelitis diagnosed on MRI was not confirmed on the biopsy (false positive). In 4 cases both MRI and biopsy excluded osteomyelitis (true negative) and in 4 cases the MRI images were negative and the biopsy was positive (false negative). The sensitivity and specificity were respectively 90% and 50%, PPV: 90% NPP:50%.  

MRI is a highly sensitive imaging modality in diagnosing osteomyelitis (concordant T1 and fluid sensitive signal changes and associated soft tissue findings) when compared to bone biopsy. It can also help distinguishing it from other pathologies commonly seen in diabetic foot. Moreover it allows a more precise evaluation of extend of the abnormality to help in decision making of therapeutic management of these patients.    

MRI is highly sensitive modality to evaluate osteomyelitis when compared to bone biopsy, it can also distinguish it from other pathologies to optimize the therapeutic management of diabetic foot.

Fatone, E, Copeland, J, Savastano, M, Beltran, J, Comparison Between MRI and Bone Biopsy in the Diagnosis of Osteomyelitis in Patients with Diabetic Foot.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12032655.html