title: Assessment of chemotherapeutic response in children with proptosis due to optic nerve glioma.
abstract: BACKGROUND
  Some children with optic pathway gliomas present with proptosis related to intraorbital tumor extension. The radiological assessment of chemotherapeutic response in these patients can be complicated by irregular tumor shape and lack of relation between tumor volume and cosmetic effect.
  
  
  METHODS
  We propose that proptosis measurements and derivation of a proptosis index can be a useful adjunct to the measurement of tumor volume in the radiological assessment of chemotherapeutic response. The proptosis index was derived as the ratio of the difference in proptosis between eyes postchemotherapy to that prechemotherapy. A series of six patients with proptosis and the diagnosis of an optic nerve tumor from an optic pathway glioma registry demonstrate by case example the correlation between the proptosis index and the clinical and radiographic response to chemotherapy.
  
  
  CONCLUSIONS
  We have found that a proptosis index <1 correlates with a chemotherapeutic maintained response and an index >1 correlates with progressive disease.
authors.affiliation: Division of Neurosurgery, Department of Clinical Neurosciences, Foothills Medical Centre, University of Calgary, 1403-29th St. N.W., Calgary, AB, Canada T2N 2T9.
authors.forename: Roberto Jose
authors.initials: RJ
authors.lastname: Diaz
authors.forename: Suzanne
authors.initials: S
authors.lastname: Laughlin
authors.forename: Gary
authors.initials: G
authors.lastname: Nicolin
authors.forename: J Raymond
authors.initials: JR
authors.lastname: Buncic
authors.forename: Eric
authors.initials: E
authors.lastname: Bouffet
authors.forename: Ute
authors.initials: U
authors.lastname: Bartels
mesh_terms: D002675:Child, Preschool; D004358:Drug Therapy / Q000379:methods*; D005094:Exophthalmos / Q000188:drug therapy* / Q000209:etiology*; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D020339:Optic Nerve Glioma / Q000150:complications* / Q000188:drug therapy; D019574:Optic Nerve Neoplasms / Q000150:complications* / Q000188:drug therapy; D017063:Outcome Assessment, Health Care / Q000379:methods*; D012189:Retrospective Studies; D015898:Tomography Scanners, X-Ray Computed; D014785:Vision, Ocular / Q000502:physiology