Distinguishing CT and MR Imaging Features of Postprocedural Inflammation and Infectious Spondylodiscitis After Intradiscal Electrothermal Therapy

ABSTRACT

Purpose@#To investigate whether the signal or morphological changes in the adjacent bone or soft tissue after intradiscal electrothermal therapy (IDET) occur due to postprocedural inflammation or infectious spondylodiscitis. @*Materials and Methods@#Ten patients (female:male = 5:5; age range, 18–71 years; mean age: 36.5 years) who underwent lumbar IDET between January 2018 and December 2020 and complained of fever or pain were included in this study. The presence and extent of bone marrow and paraspinal soft tissue signal changes were evaluated using the first follow-up magnetic resonance imaging (MRI) after IDET. Signal changes in the treated discs and the presence and extent of epidural enhancement were evaluated. Additionally, we investigated the presence and margins of subchondral erosions in the vertebral body. @*Results@#Two radiologists analyzed the imaging findings by consensus. Six patients were diagnosed with postprocedural inflammation and four with infectious spondylodiscitis, which was confirmed by specimen culture after surgery. All 10 patients showed signal changes in the bone marrow of the vertebral bodies adjacent to the treated disc. Signal changes in the paraspinal soft tissue were observed in only five patients: three with infectious spondylodiscitis and two with postprocedural inflammation. In six patients with postprocedural inflammation, subchondral erosions had well-defined margins with a sclerotic rim and in four patients with infectious spondylodiscitis, subchondral erosions had ill-defined margins. Epidural enhancement showed an extensive pattern in all cases of infectious spondylodiscitis and localized patterns in cases of postprocedural inflammation. @*Conclusion@#MRI or computed tomography findings of well-defined subchondral erosions with a sclerotic rim and more localized signal changes in the paraspinal soft tissue or epidural space might aid in the differentiation of infectious spondylodiscitis and postprocedural inflammation in patients who underwent IDET.