There is poor correlation between clinical response and resolution of findings on magnetic resonance imaging (MRI), computed tomography (CT), and nuclear studies in patients with osteomyelitis. Because radiologic resolution may lag behind clinical improvement, repeat imaging may lead to unnecessary prolongation of antimicrobial therapy. Repeat imaging is indicated in cases where there is a lack of clinical response, progression of clinical findings, or the presence of an undrained abscess on the initial scan.
Sources:
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Zarrouk V, et al. Imaging does not predict the clinical outcome of bacterial vertebral osteomyelitis. Rheumatology (Oxford). 2007 Feb;46(2): 292-5. PMID: 16877464.
Zimmerli W. Clinical practice. Vertebral osteomyelitis. N Engl J Med. 2010 Mar 18;362(11):1022-9. PMID: 20237348.