title: Gadolinium enhancement in newly diagnosed patients with lumbar disc herniations are associated with inflammatory peridiscal tissue reactions--evidence of fragment degradation?
abstract: OBJECTIVE
  It is debatable whether a local inflammatory tissue response caused by herniated disc material contributes to sciatic pain and/or sensorimotor deficits. The impact of inflammatory changes on local tissue remodelling, the healing process and the clinical course of disease remains unclear.
  
  
  METHODS
  In this prospective observational study, we included a total of 31 patients with a single-level, unilateral lumbar disc herniation. The diagnosis was confirmed by magnetic resonance imaging (MRI)±gadolinium. The presence of peridiscal contrast enhancement was correlated with the extent of inflammatory reactions in the herniated fragments as confirmed by immunohistochemistry; clinical symptoms, including the duration of radicular pain; and the incidence of sensorimotor deficits.
  
  
  RESULTS
  Peridiscal contrast enhancement was found in 17 patients (55%) and was encasing the adjacent rootlet in 4 cases. There was no significant correlation between gadolinium uptake and the presence of sensorimotor deficits or the duration of radicular symptoms. Degenerative changes were observed in all 31 disc specimens. Overall, 18 cases exhibited increased cellularity in the marginal areas, which were mostly populated by CD68(+) macrophages and fibroblasts. Additionally, these areas displayed a limited number of CD3(+) T-lymphocytes and different degrees of concomitant neovascularisation, which represented a chronic and unspecific immune response. Peridiscal contrast enhancement on MRI was significantly correlated with the histopathological characteristics of tissue inflammation. However, no correlation was found between the histological evidence and the degree of inflammation and neurological symptoms.
  
  
  CONCLUSIONS
  Gadolinium-enhanced MRI is a sensitive method to detect unspecific inflammatory reactions in therapy-naïve disc herniations. However, the neuroradiological and histological evidence of peridiscal inflammation was not correlated with the severity of pain or sensorimotor deficits in our patients. Additional research is needed because the occurrence of local inflammation may indicate an ongoing degradation of herniated fragments and thus be helpful in therapeutic decision-making.
authors.affiliation: Department of Neurosurgery, University of Würzburg, Würzburg, Germany.
authors.forename: Mario
authors.initials: M
authors.lastname: Löhr
authors.affiliation: Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité, Campus Benjamin Franklin, Berlin, Germany.
authors.forename: Lydia
authors.initials: L
authors.lastname: Lebenheim
authors.affiliation: Department of Neuroradiology, University of Würzburg, Würzburg, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Berg
authors.affiliation: Department of Pathology, Charité, Campus Benjamin Franklin, Berlin, Germany.
authors.forename: Werner
authors.initials: W
authors.lastname: Stenzel
authors.affiliation: Institute of Neurophysiology, University of Cologne, Cologne, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Hescheler
authors.affiliation: Institute of Neurophysiology, University of Cologne, Cologne, Germany; Department of Neurosurgery, University of Cologne, Cologne, Germany.
authors.forename: Marek
authors.initials: M
authors.lastname: Molcanyi
authors.affiliation: Department of Neurosurgery, University of Würzburg, Würzburg, Germany.
authors.forename: Ralf-Ingo
authors.initials: RI
authors.lastname: Ernestus
authors.affiliation: Department of Neurology, University of Duisburg-Essen, Essen, Germany; Max Planck Institute for Neurological Research with Klaus-Joachim-Zülch Laboratories of the Max Planck Society and the Medical Faculty of the University of Cologne, Cologne, Germany. Electronic address: bert.bosche@uk-essen.de.
authors.forename: Bert
authors.initials: B
authors.lastname: Bosche
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D003287:Contrast Media; D017586:Diskectomy; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007150:Immunohistochemistry; D007249:Inflammation / Q000175:diagnosis* / Q000276:immunology; D007405:Intervertebral Disc Displacement / Q000175:diagnosis* / Q000276:immunology / Q000503:physiopathology; D008159:Lumbar Vertebrae / Q000276:immunology / Q000473:pathology*; D008264:Macrophages / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000473:pathology; D011446:Prospective Studies; D013601:T-Lymphocytes / Q000276:immunology / Q000473:pathology
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA
keywords: Disc herniation; Gadolinium enhancement; Inflammation; Lumbar spine; Macrophages