Text and Data Mining valid from 2019-02-13
Received: 9 October 2018
Accepted: 31 January 2019
First Online: 13 February 2019
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: The study was approved by the Institutional Ethical committee of our institution with a waiver of patient consent authorization (No. 18.76). Since the design of the study is retrospective, no formal consent is required.