title: Identification of the pyramidal tract by neuronavigation based on intraoperative magnetic resonance tractography: correlation with subcortical stimulation.
abstract: OBJECTIVE
  To demonstrate the accuracy of magnetic resonance tractograpghy (MRT) in localizing the cortical spinal tract (CST) close to brain tumours by using intraoperative electric subcortical stimulation.
  
  
  METHODS
  Nine patients with intra-axial brain tumours underwent neurosurgery. Planning was based on analysis of the course of streamlines compatible with the CST. After tumour removal, intraoperative MRT was reacquired. Sites at various distance from the CST were repeatedly stimulated to assess whether registered motor evoked potential (MEP) could be elicited. All patients were assessed clinically both pre- and postoperatively.
  
  
  RESULTS
  The motor function was preserved in all patients. In all patients intraoperative MRT demonstrated shift of the bundle position caused by the surgical procedure. The distance between the estimated intraoperative CST and the point of elicited MEP was 1 cm or less in all nine patients. At distances greater than 2 cm, no patient reported positive MEP.
  
  
  CONCLUSIONS
  Intraoperative MRT is a reliable technique for localization of CST. In all patients MEP were elicited by direct subcortical electrical stimulation at a distance below 1 cm from the CST as represented by MRT. Brain shifting might impact this evaluation since CST position may change during surgery in the range of 8 mm.
authors.affiliation: Department of Neuroradiology, University of Rome Sapienza, Ospedale Sant'Andrea, Via di Grottarossa 1034, 00189, Rome, Italy. alessandro.bozzao@uniroma1.it
authors.forename: Alessandro
authors.initials: A
authors.lastname: Bozzao
authors.forename: Andrea
authors.initials: A
authors.lastname: Romano
authors.forename: Albina
authors.initials: A
authors.lastname: Angelini
authors.forename: Giancarlo
authors.initials: G
authors.lastname: D'Andrea
authors.forename: Luigi Fausto
authors.initials: LF
authors.lastname: Calabria
authors.forename: Valeria
authors.initials: V
authors.lastname: Coppola
authors.forename: Luciano
authors.initials: L
authors.lastname: Mastronardi
authors.forename: Luigi Maria
authors.initials: LM
authors.lastname: Fantozzi
authors.forename: Luigi
authors.initials: L
authors.lastname: Ferrante
mesh_terms: D000368:Aged; D001921:Brain / Q000473:pathology / Q000601:surgery; D001931:Brain Mapping / Q000379:methods*; D001932:Brain Neoplasms / Q000473:pathology; D056324:Diffusion Tensor Imaging / Q000379:methods*; D004558:Electric Stimulation; D019054:Evoked Potentials, Motor / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D038361:Neuronavigation / Q000379:methods; D019635:Neurosurgical Procedures / Q000379:methods; D011712:Pyramidal Tracts / Q000473:pathology*; D015203:Reproducibility of Results
references.citation: J Neurol Neurosurg Psychiatry. 2005 Jun;76(6):845-51
references.pmid: 15897509
references.citation: Neurosurgery. 1998 Oct;43(4):749-58; discussion 758-60
references.pmid: 9766300
references.citation: Radiology. 2005 Jan;234(1):218-25
references.pmid: 15564394
references.citation: Stereotact Funct Neurosurg. 2009;87(1):18-24
references.pmid: 19039259
references.citation: Radiology. 2006 Sep;240(3):849-57
references.pmid: 16857980
references.citation: Neuroimage. 2008 Jan 1;39(1):369-82
references.pmid: 17911032
references.citation: Radiol Med. 2007 Sep;112(6):906-920
references.pmid: 17891343
references.citation: Neuroimage. 2006 May 1;30(4):1100-11
references.pmid: 16427322
references.citation: J Neurooncol. 1997 Aug;34(1):85-101
references.pmid: 9210055
references.citation: J Neurosurg. 2005 Apr;102(4):664-72
references.pmid: 15871509
references.citation: Neuroimage. 2006 May 1;30(4):1219-29
references.pmid: 16364659
references.citation: Neurosurgery. 2005;56(1):130-7; discussion 138
references.pmid: 15617595
references.citation: Neurosurgery. 2006 Apr;58(4 Suppl 2):ONS-292-303; discussion ONS-303-4
references.pmid: 16582653
references.citation: Neuroimage. 2001 Sep;14(3):723-35
references.pmid: 11506544
references.citation: J Neurosurg. 2007 Apr;106(4):593-8
references.pmid: 17432708
references.citation: Neuroimage. 2005 Apr 1;25(2):424-9
references.pmid: 15784421
references.citation: Zhonghua Wai Ke Za Zhi. 2006 Sep 15;44(18):1275-9
references.pmid: 17147897
references.citation: NMR Biomed. 2002 Nov-Dec;15(7-8):468-80
references.pmid: 12489096
references.citation: Neurosurgery. 2008 Apr;62(4):753-64; discussion 264-6
references.pmid: 18496181
references.citation: Magn Reson Med. 2000 Oct;44(4):625-32
references.pmid: 11025519
references.citation: J Neurosurg. 2003 Apr;98(4):764-78
references.pmid: 12691401
references.citation: Acta Neurochir (Wien). 2004 Apr;146(4):369-77; discussion 377
references.pmid: 15057531
references.citation: Eur Radiol. 2009 Dec;19(12):2798-808
references.pmid: 19533147
references.citation: J Neurosurg. 2004 Jul;101(1):66-72
references.pmid: 15255253
references.citation: Neurosurgery. 2001 Apr;48(4):787-97; discussion 797-8
references.pmid: 11322439