Significance of repeat magnetic resonance imaging in diagnosing vertebral osteomyelitis

Vertebral osteomyelitis can result in serious complications if diagnosis is delayed. Magnetic resonance imaging (MRI) is considered the most useful modality for the early diagnosis of vertebral osteomyelitis. We examined three patients with vertebral osteomyelitis whose initial MRI (obtained <2 weeks after the onset of symptoms) did not reveal obvious findings of pyogenic vertebral osteomyelitis. However, follow-up MRI clearly demonstrated typical findings of the disease. This case series illustrates that a repeat MRI must be performed 2-4 weeks after the onset of symptoms in patients presenting with clinical manifestations and microbiological findings suggestive of vertebral osteomyelitis.