Funding for this research was provided by:
National Institute for Health Research (NIHR-RP-R3-12-027)
Medical Research Council (MR/M008894/1)
Wellcome Trust (205188/Z/16/Z)
Received: 26 April 2018
Accepted: 24 October 2018
First Online: 3 December 2018
Ethics approval and consent to participate
: Approval for analysis of imaging data was granted by the local research ethics committee and consent was waived for this retrospective database study.
: The authors declare that they have no competing interests.
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