title: Intraoperative near-infrared fluorescence imaging of a paraganglioma using methylene blue: A case report.
abstract: BACKGROUND
  Intraoperative identification of tumors can be challenging. Near-infrared (NIR) fluorescence imaging is an innovative technique that can assist in intraoperative identification of tumors, which may otherwise be undetectable.
  
  
  METHODS
  A 19-year-old patient with symptoms, normetanephrine levels and radiological findings suspicious for a paraganglioma, a rare tumor arising from extra-adrenal chromaffin cells within the sympathetic nervous system, is presented. Intraoperative NIR fluorescence imaging using intravenous administration of methylene blue (MB) assisted in intraoperative detection of the tumor, and even identified a smaller second lesion, which was not identified during surgery by visual inspection.
  
  
  CONCLUSIONS
  Although the exact mechanism of MB accumulation in neuroendocrine tumors is unclear, it is described in both preclinical and clinical studies.
  
  
  CONCLUSIONS
  In this report, we describe the first case of intraoperative NIR fluorescence imaging of a paraganglioma using MB, which identified an otherwise undetectable lesion.
authors.affiliation: Department of Surgery, Leiden, University Medical Center, Albinusdreef 2, 2300 RC, Leiden, The Netherlands.
authors.forename: Quirijn R J G
authors.initials: QR
authors.lastname: Tummers
authors.affiliation: Department of Surgery, Leiden, University Medical Center, Albinusdreef 2, 2300 RC, Leiden, The Netherlands.
authors.forename: Martin C
authors.initials: MC
authors.lastname: Boonstra
authors.affiliation: Department of Medicine, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215, USA; Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215, USA.
authors.forename: John V
authors.initials: JV
authors.lastname: Frangioni
authors.affiliation: Department of Surgery, Leiden, University Medical Center, Albinusdreef 2, 2300 RC, Leiden, The Netherlands.
authors.forename: Cornelis J H
authors.initials: CJ
authors.lastname: van de Velde
authors.affiliation: Department of Surgery, Leiden, University Medical Center, Albinusdreef 2, 2300 RC, Leiden, The Netherlands. Electronic address: a.l.vahrmeijer@lumc.nl.
authors.forename: Alexander L
authors.initials: AL
authors.lastname: Vahrmeijer
authors.affiliation: Department of Surgery, Leiden, University Medical Center, Albinusdreef 2, 2300 RC, Leiden, The Netherlands.
authors.forename: Bert A
authors.initials: BA
authors.lastname: Bonsing
keywords: Image-guided surgery; Methylene blue; Near-infrared fluorescence imaging; Neuroendocrine tumor; Paraganglioma