title: [Intraoperative photodynamic diagnosis for spinal ependymoma using 5-aminolevulinic acid: technical note].
abstract: OBJECTIVE
  The fluorescence-guided resection using 5-aminolevulinic acid (5-ALA) is a well established method for the treatment of brain tumor, especially malignant glioma. However, there is no report on photodynamic diagnosis (PDD) for spinal tumor. In the present study, we evaluated the usefulness of PDD for spinal ependymoma using 5-ALA.
  
  
  METHODS
  Three patients with spinal ependymoma received oral doses of 5-ALA (20 mg/kg body weight) 2 hours before anesthesia induction. Intraoperatively, fluorescence was observed with a 420 nm sharp cut filter after excitation with a violet semiconductor laser (405 nm) and was verified by analysis of fluorescent spectra. Residual fluorescent samples taken from the tumor cavity were examined histologically
  
  
  RESULTS
  Fluorescence peaked at 636nm in the removed tumors in all cases. Fluorescent tissue tended to exist at the cranial and caudal portion in the tumor cavity or around the anterior median fissure. The residual fluorescent tissue was not detected after removal of the tumor in case 1. The residual fluorescent tissue was composed of tumor cells and ependymal lining in case 2 or the infiltrated inflammatory cells and vascular endothelial cells in case 3. Postoperative magnetic resonance (MR) imaging showed no residual tumor in any of the cases.
  
  
  CONCLUSIONS
  The results of this study indicate the usefulness of 5-ALA-induced tumor fluorescence in guiding resection of spinal ependymoma. 5-ALA-induced porphyrin fluorescence may label spinal ependymomas easily and clearly enough to enhance the completeness of tumor removal.
authors.affiliation: Department of Neurosurgery, Jikei University School of Medicine, 3-26-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan. takao-a@jikei.ac.jp
authors.forename: Takao
authors.initials: T
authors.lastname: Arai
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tani
authors.forename: Akira
authors.initials: A
authors.lastname: Isoshima
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Nagashima
authors.forename: Tatsuhiro
authors.initials: T
authors.lastname: Joki
authors.forename: Junko
authors.initials: J
authors.lastname: Takahashi-Fujigasaki
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Abe
mesh_terms: D000328:Adult; D000622:Aminolevulinic Acid; D004806:Ependymoma / Q000175:diagnosis* / Q000601:surgery; D005260:Female; D005453:Fluorescence; D006801:Humans; D007432:Intraoperative Period; D008029:Lighting; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D017319:Photosensitizing Agents; D011166:Porphyrins; D012680:Sensitivity and Specificity; D013120:Spinal Cord Neoplasms / Q000175:diagnosis* / Q000601:surgery
chemical_list: D017319:Photosensitizing Agents; D011166:Porphyrins; D000622:Aminolevulinic Acid