title: The visual impact of fractionated stereotactic conformal radiotherapy on seven eyes with optic nerve sheath meningiomas.
abstract: BACKGROUND
  Treatment of primary optic nerve sheath meningiomas (ONSMs) remains controversial. Although recent studies have suggested a favorable outcome of radiotherapy, controlled data on the efficacy of fractionated stereotactic conformal radiotherapy (SCRT) in primary ONSMs are still lacking.
  
  
  METHODS
  Seven eyes treated with SCRT (total dose: 54 Gy) were compared with six eyes that were not treated because of patient or physician preference. The indication for intervention was deterioration of visual function with or without imaging evidence of tumor progression. Patients with secondary ONSMs and those with neurofibromatosis type 2 were excluded. The mean follow-up period was 57 months for the treated eyes and 61 months for the untreated eyes.
  
  
  RESULTS
  Among the seven treated eyes, visual acuity improved in six, five of which sustained improvement of three or more Snellen lines. One eye deteriorated by two lines. Visual field improved in four eyes, remained stable in two, and deteriorated in one. Four untreated eyes showed worsening of visual acuity and two remained stable. Visual field deteriorated in three eyes and was stable in three. None of the untreated eyes experienced improvement in visual acuity or visual field. No complications of treatment were documented.
  
  
  CONCLUSIONS
  In agreement with previous reports, these results indicate that SCRT is superior to observation in its impact on visual function in eyes with primary ONSMs.
authors.affiliation: Department of Ophthalmology, University Hospital Zurich, Frauenklinikstrasse 24, 8091 Zurich, Switzerland.
authors.forename: Monika
authors.initials: M
authors.lastname: Landert
authors.forename: Brigitta G
authors.initials: BG
authors.lastname: Baumert
authors.forename: Martina M
authors.initials: MM
authors.lastname: Bosch
authors.forename: Urs M
authors.initials: UM
authors.lastname: Lütolf
authors.forename: Klara
authors.initials: K
authors.lastname: Landau
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008577:Meningeal Neoplasms / Q000175:diagnosis / Q000503:physiopathology / Q000532:radiotherapy*; D008579:Meningioma / Q000175:diagnosis / Q000503:physiopathology / Q000532:radiotherapy*; D008875:Middle Aged; D019574:Optic Nerve Neoplasms / Q000175:diagnosis / Q000503:physiopathology / Q000532:radiotherapy*; D020266:Radiotherapy, Conformal; D013238:Stereotaxic Techniques; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology*