title: Intraoperative magnetic resonance imaging and early prognosis for vision after transsphenoidal surgery for sellar lesions.
abstract: OBJECTIVE
  Sellar lesions with suprasellar extension may cause loss of visual acuity and visual field damage due to compression of the optic chiasm. Using intraoperative MR (iMR) imaging to detect symptomatic lesion remnants adjacent to the optic chiasm (that may be resected in the same procedure) may positively affect the functional outcome of patients with these lesions. The aim of this study was to evaluate the correlation between visual improvement and optic nerve decompression detected by iMR imaging in patients undergoing transsphenoidal resection of pituitary lesions.
  
  
  METHODS
  A total of 32 patients (23 men and 9 women) who underwent transsphenoidal resection of sellar lesions causing visual impairment were included in this study. Tumor volume ranged from 0.9 cm(3) to 55.7 cm(3) (mean 9.8 ± 11.7 cm(3)). Preoperative assessment showed visual field damage in 31 patients (97%) and loss of visual acuity in 28 patients (88%). The latency period between the appearance of symptoms and transsphenoidal decompression was 14.9 ± 19.5 weeks.
  
  
  RESULTS
  Intraoperative MR imaging was performed after the resection was believed to be complete, or if further tumor removal was not safely possible due to changed conditions in the surgical field. Complete resection was detected on these initial scans in 17 patients (53%). Partial resection was achieved in 9 patients (28%) and tumor debulking in 6 (19%). Additional resection was possible in 8 (53%) of these 15 patients. Four (50%) of these 8 cases had suprasellar remnants and the optic chiasm was subsequently decompressed. In 5 cases optimal decompression of the optic chiasm was not possible. On early follow-up within 1 month after surgery, overall improvement of visual field damage was observed in 27 patients (87%). In 23 patients (74%), the Goldmann perimetry demonstrated complete recovery. Improvement of visual acuity was noted in 24 patients (86%). Eighteen patients (64%) regained full visual acuity. Identification of a decompressed optic chiasm on iMR imaging was significantly correlated with visual field improvement (p = 0.0007; positive predictive value 0.96, 95% CI 0.81-0.99) and relief of visual acuity deficits (p = 0.0002; positive predictive value 0.96, 95% CI 0.79-0.99). Two patients needed transcranial procedures for symptomatic tumor remnants detected on iMR imaging.
  
  
  CONCLUSIONS
  Intraoperative MR imaging findings correlate with prognosis of visual deficits after transsphenoidal decompression of the anterior optic pathways. The use of iMR imaging may prevent revision surgery for unexpected symptomatic remnants.
authors.affiliation: Department of Neurosurgery, Kantonsspital Aarau, Switzerland.
authors.forename: Sven
authors.initials: S
authors.lastname: Berkmann
authors.forename: Javier
authors.initials: J
authors.lastname: Fandino
authors.forename: Sascha
authors.initials: S
authors.lastname: Zosso
authors.forename: Hanspeter E
authors.initials: HE
authors.lastname: Killer
authors.forename: Luca
authors.initials: L
authors.lastname: Remonda
authors.forename: Hans
authors.initials: H
authors.lastname: Landolt
mesh_terms: D000236:Adenoma / Q000473:pathology / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D019635:Neurosurgical Procedures / Q000379:methods; D010911:Pituitary Neoplasms / Q000473:pathology / Q000601:surgery*; D011379:Prognosis; D012658:Sella Turcica / Q000473:pathology / Q000601:surgery; D014785:Vision, Ocular; D058609:Visual Field Tests