title: Decompression of idiopathic lumbar epidural lipomatosis: diagnostic magnetic resonance imaging evaluation and review of the literature.
abstract: OBJECTIVE
  Idiopathic symptomatic spinal epidural lipomatosis (SEL) is a rare condition, and few reports have discussed diagnostic imaging criteria. To evaluate factors relating to its clinical symptoms, correlations between clinical features and the presence of spinal epidural fat were investigated, and the literature concerning idiopathic SEL was reviewed.
  
  
  METHODS
  Morphological gradings of epidural fat were evaluated in seven patients with idiopathic SEL by using magnetic resonance (MR) imaging. In addition, body mass index (BMI), the number of involved vertebral levels, grade, and preoperative Japanese Orthopaedic Association (JOA) score were analyzed. Surgery resulted in symptomatic relief, with a mean JOA score recovery rate of 67.4%. Grading of epidural fat tended to display a slight negative correlation with preoperative JOA score, whereas a strong significant positive correlation was found between the number of involved vertebral levels and BMI.
  
  
  CONCLUSIONS
  The number of involved vertebral levels and obesity are strongly correlated, whereas severity of dural compression is not always significantly associated with neurological complications. These results indicate that epidural fat of the lumbar spine contributes to neurological deficits. In addition, weight-reduction therapy appears to decrease the number of vertebral levels involved. Magnetic resonance imaging-based grading is helpful for the diagnosis and evaluation of idiopathic lumbar SEL. Moreover, symptoms and neurological findings are important for determining the surgical approach.
authors.affiliation: Department of Orthopedic Surgery, Akita University School of Medicine, Japan. mitsuki@rio.odn.ne.jp
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Shimada
authors.forename: Naohisa
authors.initials: N
authors.lastname: Miyakoshi
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Suzuki
authors.forename: Michio
authors.initials: M
authors.lastname: Hongo
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kasukawa
authors.forename: Kyoji
authors.initials: K
authors.lastname: Okada
authors.forename: Eiji
authors.initials: E
authors.lastname: Itoi
mesh_terms: D000273:Adipose Tissue; D000328:Adult; D000368:Aged; D019299:Decompression, Surgical; D003937:Diagnosis, Differential; D004824:Epidural Space / Q000473:pathology; D005260:Female; D006801:Humans; D008068:Lipomatosis / Q000150:complications / Q000473:pathology* / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications; D012189:Retrospective Studies; D013118:Spinal Cord Diseases / Q000150:complications / Q000473:pathology* / Q000601:surgery*; D016896:Treatment Outcome