title: Macrocephaly in neurofibromatosis type 1: a sign post for optic pathway gliomas?
abstract: OBJECTIVE
  Optic pathway gliomas, which occur in 15-20% of paediatric patients with neurofibromatosis type 1, are the most common central nervous system tumour associated with this neurocutaneous disorder. The detection of optic pathway gliomas is essential for further management but is often delayed in infancy due to oligosymptomatic progression and difficulties in clinical detection. Therefore, the aim of our study was to find a clinical indicator for the presence of optic pathway gliomas in children with neurofibromatosis type 1 in order to facilitate early diagnosis and initiate further ophthalmological and neuroimaging investigations.
  
  
  METHODS
  We retrospectively evaluated 70 patients (mean age of 10.5 years; SD of 4.3 years; range of 0.5-19.6 years; 35 females) with neurofibromatosis type 1 seen at the University Children's Hospital of Bern, Switzerland, between January 1998 and December 2008 regarding clinical features of neurofibromatosis type 1 in relation to the presence of optic pathway gliomas.
  
  
  RESULTS
  Fifty-seven of the 70 patients (81.4%) had no clinical or radiological signs of optic pathway gliomas [magnetic resonance imaging (MRI) of the brain in 26/57], whereas 13/70 patients (18.6%) were diagnosed with optic pathway gliomas by MRI. Patients with optic pathway gliomas showed macrocephaly significantly more often compared to patients without optic pathway gliomas (8/13 vs. 9/57, respectively; p = 0.004).
  
  
  CONCLUSIONS
  Macrocephaly significantly correlates with the incidence of optic pathway gliomas in children with neurofibromatosis type 1. We therefore hypothesise that in otherwise asymptomatic patients, macrocephaly is an additional indicator for performing MRI to detect optic pathway gliomas.
authors.affiliation: Paediatric Neurology, University Children's Hospital, Inselspital, 3010 Bern, Switzerland. christina.schindera@gmx.de
authors.forename: Christina
authors.initials: C
authors.lastname: Schindera
authors.forename: Kevin
authors.initials: K
authors.lastname: Wingeier
authors.forename: Barbara
authors.initials: B
authors.lastname: Goeggel Simonetti
authors.forename: Miriam
authors.initials: M
authors.lastname: Diepold
authors.forename: Claude B
authors.initials: CB
authors.lastname: Nauer
authors.forename: Johannes
authors.initials: J
authors.lastname: Fleischhauer
authors.forename: Maja
authors.initials: M
authors.lastname: Steinlin
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D058627:Megalencephaly / Q000209:etiology*; D009456:Neurofibromatosis 1 / Q000150:complications* / Q000175:diagnosis*; D020339:Optic Nerve Glioma / Q000150:complications* / Q000175:diagnosis*; D012189:Retrospective Studies; D014786:Vision Disorders / Q000209:etiology; D055815:Young Adult