Hourfar, Jan
Kinzinger, Gero Stefan Michael
Euchner, Luisa
Lisson, Jörg Alexander
Article History
Received: 22 May 2019
Accepted: 7 October 2019
First Online: 9 November 2019
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.
: This article does not contain any studies with human participants or animals performed by any of the authors. Ethical approval for this retrospective study was granted by the Ethics Commission of University of Aachen, Germany, No. 171/08.
: For this type of study, formal consent is not required.