Received: 3 September 2018
Accepted: 15 January 2019
First Online: 21 January 2019
Ethics approval and consent to participate
: This study adhered to the tenets of the Declaration of Helsinki. For this retrospective type of study formal consent is not required according the regulations of the IRB Universitiy Medical Center Schleswig-Holstein. Informed written consent for participation was obtained from the patients or from the parents of the patients under the age of 18.
: Consent for publication was obtained from the patients and parents of children under 18 whose photos were used in the manuscript.
: The authors declare that they have no competing interests.
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