title: The open fontanelle: a window to less radiation.
abstract: BACKGROUND
  Over the years, there has been increasing awareness of the radiation doses from medical investigation and treatment modalities and the long-term effect of this radiation. In no other patient population is this more of an issue than in the paediatric population who are more radiosensitive and have a longer life span in which to express any negative effects of radiation. In children under the age of one, the anterior fontanelle is an acoustic window to intracranial structures allowing for the use of cranial ultrasound (CRUSS) instead of CT.
  
  
  OBJECTIVE
  To determine the pattern of CT and Cranial ultrasound used in patients aged one or younger with shunt treated hydrocephalus.
  
  
  METHODS
  A retrospective review of patients who had a shunt inserted before the age of one and their imaging. Effective radiation doses were calculated for those who had CT scans.
  
  
  RESULTS
  One hundred thirty-five patients were included with 227 CTs and 124 CRUSS conducted. In the follow-up period after shunt insertion, 92 patients had CTs while 14 were followed with CRUSS and 51 patients required a shunt revision before the age of one. The average effective radiation dose per scan was 2.76 mSv.
  
  
  CONCLUSIONS
  Children with an open fontanelle and shunt can be followed reliably with CRUSS in order to reduce their exposure to radiation.
authors.affiliation: Department of Paediatric Neurosurgery, Children's University Hospital, Temple Street, Dublin 1, Republic of Ireland. fadzi411@gmail.com.
authors.forename: Tafadzwa
authors.initials: T
authors.lastname: Mandiwanza
authors.affiliation: Department of Radiology, Children's University Hospital, Temple Street, Dublin 1, Republic of Ireland.
authors.forename: Colm
authors.initials: C
authors.lastname: Saidlear
authors.affiliation: Department of Paediatric Neurosurgery, Children's University Hospital, Temple Street, Dublin 1, Republic of Ireland.
authors.forename: John
authors.initials: J
authors.lastname: Caird
authors.affiliation: Department of Paediatric Neurosurgery, Children's University Hospital, Temple Street, Dublin 1, Republic of Ireland.
authors.forename: Darach
authors.initials: D
authors.lastname: Crimmins
mesh_terms: D002557:Cerebrospinal Fluid Shunts / Q000379:methods; D015331:Cohort Studies; D055762:Cranial Fontanelles; D004453:Echoencephalography; D005260:Female; D006801:Humans; D006849:Hydrocephalus / Q000000981:diagnostic imaging* / Q000209:etiology / Q000601:surgery; D007223:Infant; D020300:Intracranial Hemorrhages / Q000150:complications; D008297:Male; D008591:Meningomyelocele / Q000150:complications; D011829:Radiation Dosage; D000069079:Radiation Exposure / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
keywords: Anterior fontanelle; Cranial ultrasound; Effective radiation dose; Hydrocephalus