A comparison of the diagnostic value of MRI and FDG-PET/CT in suspected spondylodiscitis
Kouijzer, I.J.E., Smids, C., Vos, F.J., Sprong, T., Hosman, A.J.F., Oyen, W.J.G., Bleeker-Rovers, C.P.
Voorzitter(s): prof.dr. J.W. de Fijter, Leiden & dr. P.J. de Vries, Hilversum
Locatie(s): Zaal 0.5
Categorie(ën):
Introduction: Spondylodiscitis is becoming more common in an increasingly ageing population. Early and accurate detection is crucial for successful management and improved neurological outcome. Contrast enhanced MRI is the modality of choice in current clinical practice, but sensitivity is suboptimal in the early stage of infection. We hypothesized that FDG-PET/CT might be more accurate by using pathophysiology instead of depending on anatomical changes.
Aim of the study: The purpose of this study was to evaluate the value of FDG-PET/CT and contrast enhanced MRI in diagnosing spondylodiscitis and its complications.
Materials and Methods: From January 2006 to August 2013 patients with a clinical suspicion of spondylodiscitis, with an infection or with fever of unknown origin were retrospectively included if they underwent both FDG-PET/CT and MRI of the spine within two weeks from each other. Results were compared to the final clinical diagnosis.
Results: 70 patients were included of whom 50 were finally diagnosed with spondylodiscitis. MRI showed an overall sensitivity of 64% and specificity of 85%. Diagnostic accuracy improved from 56% when MRI was performed within two weeks after start of symptoms to 80% when MRI was performed after two weeks. FDG-PET/CT showed a significantly higher sensitivity of 98% and specificity of 95% resulting in a significantly higher overall accuracy (97% vs. 70% for MRI), with no differences when performed either within or after two weeks from start of symptoms. MRI showed to be the modality of choice in diagnosing epidural and spinal abscesses with a sensitivity of 94% (vs. 44% for FDG-PET/CT). FDG-PET/CT showed a higher sensitivity in diagnosing paravertebral (95%) and psoas abscesses (100%), as compared to MRI (63% and 62%, respectively).
Conclusion: As compared to MRI, FDG-PET/CT has superior diagnostic value for early detection of spondylodiscitis within two weeks after first symptoms. After two weeks, both techniques have a similar yield. MRI showed highest sensitivity in diagnosing epidural en spinal abscesses while FDG-PET/CT was more sensitive in diagnosing paravertebral and psoas abscesses.
- Over Kouijzer, I.J.E.
- Over Smids, C.
- Over Vos, F.J.
- Over Sprong, T.
- Over Hosman, A.J.F.
- Over Oyen, W.J.G.
- Over Bleeker-Rovers, C.P.