title: Meningioma causing visual impairment: outcomes and toxicity after intensity modulated radiation therapy.
abstract: OBJECTIVE
  To evaluate ophthalmologic outcomes and toxicity of intensity modulated radiation therapy (IMRT) in patients with meningiomas causing visual deficits.
  
  
  METHODS
  A prospective observational study with formal ophthalmologic and clinical assessment of 30 consecutive cases of meningioma affecting vision treated with IMRT from 2007 to 2011. Prescriptions were 50.4 Gy to mean target dose in 28 daily fractions. The median follow-up time was 28 months. Twenty-six meningiomas affected the anterior visual pathway (including 3 optic nerve sheath meningiomas); 4 were posterior to the chiasm.
  
  
  RESULTS
  Vision improved objectively in 12 patients (40%). Improvements were in visual field (5/16 patients), color vision (4/9 patients), acuity (1/15 patients), extraocular movements (3/11 patients), ptosis (1/5 patients), and proptosis (2/6 patients). No predictors of clinical response were found. Two patients had minor reductions in tumor dimensions on magnetic resonance imaging, 1 patient had radiological progression, and the other patients were stable. One patient experienced grade 2 keratitis, 1 patient had a minor visual field loss, and 5 patients had grade 1 dry eye.
  
  
  CONCLUSIONS
  IMRT is an effective method for treating meningiomas causing ophthalmologic deficits, and toxicity is minimal. Thorough ophthalmologic assessment is important because clinical responses often occur in the absence of radiological change.
authors.affiliation: Radiotherapy Department, University College London Hospital, London, UK. jillian.maclean@uclh.nhs.uk
authors.forename: Jillian
authors.initials: J
authors.lastname: Maclean
authors.forename: Naomi
authors.initials: N
authors.lastname: Fersht
authors.forename: Fion
authors.initials: F
authors.lastname: Bremner
authors.forename: Chris
authors.initials: C
authors.lastname: Stacey
authors.forename: Suganya
authors.initials: S
authors.lastname: Sivabalasingham
authors.forename: Susan
authors.initials: S
authors.lastname: Short
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D055253:Color Vision / Q000502:physiology / Q000528:radiation effects; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D008297:Male; D008577:Meningeal Neoplasms / Q000150:complications / Q000532:radiotherapy*; D008579:Meningioma / Q000150:complications / Q000532:radiotherapy*; D008875:Middle Aged; D011446:Prospective Studies; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects; D016896:Treatment Outcome; D014786:Vision Disorders / Q000209:etiology / Q000532:radiotherapy*; D014792:Visual Acuity / Q000502:physiology / Q000528:radiation effects; D014794:Visual Fields / Q000502:physiology / Q000528:radiation effects; D014795:Visual Pathways / Q000528:radiation effects