title: The utility of high-resolution intraoperative MRI in endoscopic transsphenoidal surgery for pituitary macroadenomas: early experience in the Advanced Multimodality Image Guided Operating suite.
abstract: OBJECTIVE
  Endoscopic skull base surgery has become increasingly popular among the skull base surgery community, with improved illumination and angled visualization potentially improving tumor resection rates. Intraoperative MRI (iMRI) is used to detect residual disease during the course of the resection. This study is an investigation of the utility of 3-T iMRI in combination with transnasal endoscopy with regard to gross-total resection (GTR) of pituitary macroadenomas.
  
  
  METHODS
  The authors retrospectively reviewed all endoscopic transsphenoidal operations performed in the Advanced Multimodality Image Guided Operating (AMIGO) suite from November 2011 to December 2014. Inclusion criteria were patients harboring presumed pituitary macroadenomas with optic nerve or chiasmal compression and visual loss, operated on by a single surgeon.
  
  
  RESULTS
  Of the 27 patients who underwent transsphenoidal resection in the AMIGO suite, 20 patients met the inclusion criteria. The endoscope alone, without the use of iMRI, would have correctly predicted extent of resection in 13 (65%) of 20 cases. Gross-total resection was achieved in 12 patients (60%) prior to MRI. Intraoperative MRI helped convert 1 STR and 4 NTRs to GTRs, increasing the number of GTRs from 12 (60%) to 16 (80%).
  
  
  CONCLUSIONS
  Despite advances in visualization provided by the endoscope, the incidence of residual disease can potentially place the patient at risk for additional surgery. The authors found that iMRI can be useful in detecting unexpected residual tumor. The cost-effectiveness of this tool is yet to be determined.
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Hasan A
authors.initials: HA
authors.lastname: Zaidi
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Kenneth
authors.initials: K
authors.lastname: De Los Reyes
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Garni
authors.initials: G
authors.lastname: Barkhoudarian
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Zachary N
authors.initials: ZN
authors.lastname: Litvack
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Wenya Linda
authors.initials: WL
authors.lastname: Bi
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Jordina
authors.initials: J
authors.lastname: Rincon-Torroella
authors.affiliation: Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Mukundan
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Ian F
authors.initials: IF
authors.lastname: Dunn
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Edward R
authors.initials: ER
authors.lastname: Laws
mesh_terms: D000236:Adenoma / Q000000981:diagnostic imaging* / Q000601:surgery; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D064847:Multimodal Imaging / Q000379:methods*; D018365:Neoplasm, Residual / Q000000981:diagnostic imaging / Q000601:surgery; D044583:Neuroendoscopy / Q000379:methods*; D010911:Pituitary Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D012189:Retrospective Studies; D013100:Sphenoid Bone / Q000601:surgery
keywords: ACTH = adrenocorticotropic hormone; AMIGO; AMIGO = Advanced Multimodality Image Guided Operating; FSGR = fat spoiled gradient echo; FSH = follicle-stimulating hormone; GH = growth hormone; GTR = gross-total resection; LH = luteinizing hormone; NTR = near-total resection; STR = subtotal resection; endoscope; iMRI = intraoperative MRI; intraoperative MRI; pituitary adenomas; resection