Utility of MRI in the follow-up of pyogenic spinal infection in children

MRI is used at an increasing rate in evaluation of pediatric spinal infections both at the time of diagnosis and in follow-up. However, the impact of MRI in follow-up has been rarely evaluated to date. To evaluate serial follow-up spinal MRI changes compared to clinical outcome and assess their impact on clinical management. All pediatric (< 18 years) patients with pyogenic spinal infection over a 9-year period with at least one follow-up after treatment were included. Atypical infections were excluded. We examined 35 whole-spine and 16 localized spinal scans from 17 patients (2 months to 16 years, 9F:8 M) who had 51 follow-ups done 2 weeks to 4.75 years after baseline. Seven children (41%) younger than 3 years underwent 33 follow-ups (65%); most required GA or sedation. Short-term follow-up scans demonstrated epidural and/or paraspinal soft-tissue changes correlating with clinical status and laboratory findings in all cases. However, MRI showed that bone and/or disc abnormalities continued and progressed in some cases despite clinical improvement. Long-term follow-up scans showed bone, disc and soft-tissue changes 1-3 years after baseline, despite children being symptom free. Extension of antibiotics occurred in 47% of children partly based on follow-up MRI. Epidural and paraspinal soft-tissue changes correlated with children's clinical symptoms. Progression of bone and disc changes can manifest despite adequate clinical response. Long-term or serial routine follow-ups were not necessary. Management should be made based on clinical response.