title: Increased brain tumor resection using fluorescence image guidance in a preclinical model.
abstract: OBJECTIVE
  Fluorescence image-guided brain tumor resection is thought to assist neurosurgeons by visualizing those tumor margins that merge imperceptibly into normal brain tissue and, hence, are difficult to identify. We compared resection completeness and residual tumor, determined by histopathology, after white light resection (WLR) using an operating microscope versus additional fluorescence guided resection (FGR).
  
  
  METHODS
  We employed an intracranial VX2 tumor in a preclinical rabbit model and a fluorescence imaging/spectroscopy system, exciting and detecting the fluorescence of protoporphyrin IX (PpIX) induced endogenously by administering 5-aminolevulinic acid (ALA) at 4 hours before surgery.
  
  
  RESULTS
  Using FGR in addition to WLR significantly increased resection completeness by a factor 1.4 from 68+/-38 to 98+/-3.5%, and decreased the amount of residual tumor post-resection by a factor 16 from 32+/-38 to 2.0+/-3.5% of the initial tumor volume.
  
  
  CONCLUSIONS
  Additional FGR increased completeness of resection and enabled more consistent resections between cases.
authors.affiliation: Department of Medical Biophysics, Ontario Cancer Institute/University Health Network and University of Toronto, Toronto, Ontario, Canada M5G 2M9.
authors.forename: Arjen
authors.initials: A
authors.lastname: Bogaards
authors.forename: Abhay
authors.initials: A
authors.lastname: Varma
authors.forename: Sean P
authors.initials: SP
authors.lastname: Collens
authors.forename: Aihua
authors.initials: A
authors.lastname: Lin
authors.forename: Anoja
authors.initials: A
authors.lastname: Giles
authors.forename: Victor X D
authors.initials: VX
authors.lastname: Yang
authors.forename: Juan M
authors.initials: JM
authors.lastname: Bilbao
authors.forename: Lothar D
authors.initials: LD
authors.lastname: Lilge
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Muller
authors.forename: Brian C
authors.initials: BC
authors.lastname: Wilson
mesh_terms: D000622:Aminolevulinic Acid; D000818:Animals; D001932:Brain Neoplasms / Q000601:surgery*; D005910:Glioma / Q000601:surgery*; D008853:Microscopy / Q000379:methods; D023421:Models, Animal; D018365:Neoplasm, Residual; D019635:Neurosurgical Procedures / Q000379:methods*; D017319:Photosensitizing Agents; D011524:Protoporphyrins; D011817:Rabbits; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: D017319:Photosensitizing Agents; D011524:Protoporphyrins; D000622:Aminolevulinic Acid; C028025:protoporphyrin IX