Received: 18 May 2018
Accepted: 27 July 2018
First Online: 31 October 2018
Ethics approval and consent to participate
: Written informed consent for the use of the data for research purposes was obtained and double anonymisation of patients’ data was performed. Ethical committee approval for this retrospective study has been obtained and patients’ informed consent was waived.
: Not applicable.
: The authors declare that they have no competing interests..
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