Article History
Received: 17 December 2018
Accepted: 6 May 2019
First Online: 28 May 2019
Ethics approval and consent to participate
: This study was approved by the institutional review board of the University of Tübingen in Germany, and it adhered to the tenets of the Declaration of Helsinki. This study is a retroactive review of patient data; therefore consent was not collected from participants.
: Not applicable.
: The authors declare that they have no competing interests.None: no support from any organization for the submitted work; no financial relationships with any organizations that might have an interest in the submitted work during the previous three years; no other relationships or activities that could appear to have influenced the submitted work.
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