Toggle Main Menu Toggle Search

Open Access padlockePrints

Radiation dose to the lens from CT of the head in young people

Lookup NU author(s): Dr Richard Harbron

Downloads


Licence

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND).


Abstract

© 2019AIM: To determine cumulative scan frequencies and estimate lens dose for paediatric computed tomography (CT) head examinations in the context of potential cataract risk. MATERIALS AND METHODS: The cumulative number of head-region CT examinations among a cohort of 410,997 children and young adults who underwent CT in the UK between 1985 and 2014 was calculated. Images from a sample of these head examinations (n=668) were reviewed to determine the level of eye inclusion. Lens dose per scan was estimated using the computer program, NCICT V1.0, for different levels of eye inclusion and exposure settings typical of past and present clinical practice. RESULTS: In total 284,878 patients underwent 448,108 head-region CT examinations. The majority of patients (72%) had a single recorded head-region examination. A small subset (∼1%, n=2,494) underwent ≥10 examinations, while 0.1% (n=387) underwent ≥20. The lens was included within the imaged region for 57% of reviewed routine head examinations. In many cases, this appeared to be intentional, i.e. protocol driven. In others, there appeared to have been an attempt to exclude the eyes through gantry angulation. Estimated lens doses were 20–75 mGy (mean: 47 mGy) where the eye was fully included within the examination range and 2–7 mGy (mean: 3.1 mGy) where the lens was fully excluded. Potential cumulative lens doses ranged from ∼3 mGy to ∼4,700 mGy, with 2,335 patients potentially receiving >500 mGy. CONCLUSION: The majority of young people will receive cumulative lens doses well below 500 mGy, meaning the risk of cataract induction is likely to be very small.


Publication metadata

Author(s): Harbron RW, Ainsbury EA, Barnard SGR, Lee C, McHugh K, Berrington de Gonzalez A, Edyvean S, Pearce MS

Publication type: Article

Publication status: Published

Journal: Clinical Radiology

Year: 2019

Volume: 74

Issue: 10

Pages: 816.e9–816.e17

Print publication date: 01/10/2019

Online publication date: 30/07/2019

Acceptance date: 28/06/2019

Date deposited: 14/08/2020

ISSN (print): 0009-9260

ISSN (electronic): 1365-229X

Publisher: W.B. Saunders Ltd

URL: https://doi.org/10.1016/j.crad.2019.06.029

DOI: 10.1016/j.crad.2019.06.029


Altmetrics

Altmetrics provided by Altmetric


Funding

Funder referenceFunder name
269912
C22891/A16015Cancer Research UK CRUK (open competition)
NIHR
NO2-CP-75501
RRX119

Share