title: Magnetic resonance imaging findings of remnants of an intradural oil-based contrast agent: report of a case.
abstract: BACKGROUND
  Myodil (iophendylate), an oil-based positive contrast media, now discontinued, was widely used for performing myelography 30-70 years ago. We identified this agent as the explanation for uncommon magnetic resonance imaging (MRI) findings in a patient with  thoracic spinal fracture.
  
  
  METHODS
  Case report and literature review.
  
  
  RESULTS
  An 81-year-old man complained of back pain after falling down stairs. Anamnesis revealed that he had undergone myelography with an oil-based contrast agent about 60 years previously  as a part of the diagnostic workup for back pain and sudden onset of gait difficulty. Plain radiography of the thoraco-lumbar spine showed a fracture of the eleventh thoracic vertebra and a radio-opaque, oval shadow at the level of the T9-T10 vertebrae. Many small radio-opaque dots  with the appearance of a string of pearls were seen from T8 to L3 vertebrae. MRI revealed a sharply demarcated intradural extramedullary mass, of approximately 5 mm in diameter on the left side of the dura in the region of the T9-T10. The mass showed high signal intensity on T1-weighted  MRI, and low signal intensity on T2-weighted MRI.
  
  
  CONCLUSIONS
  Increased awareness of this rare presentation of procedures performed in the past is essential when atypical radiographic images are encountered. This case illustrates rare sequelae of Myodil use manifesting  decades after administration.
authors.affiliation: Department of Spinal Surgery and Medical Engineering, Mie University Graduate School of Medicine, Tsu, Mie, Japan.
authors.forename: Myint
authors.initials: M
authors.lastname: Oo
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Wang
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Sakakibara
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Kasai
mesh_terms: D000369:Aged, 80 and over; D003287:Contrast Media; D006801:Humans; D007481:Iophendylate; D008279:Magnetic Resonance Imaging; D008297:Male; D016103:Spinal Fractures / Q000175:diagnosis*; D013904:Thoracic Vertebrae / Q000293:injuries*
chemical_list: D003287:Contrast Media; D007481:Iophendylate