The open fontanelle: a window to less radiation.

Introduction: 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.
Aim: 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.
Conclusion: Children with an open fontanelle and shunt can be followed reliably with CRUSS in order to reduce their exposure to radiation.