Received: 9 November 2017
Accepted: 27 March 2018
First Online: 25 April 2018
Ethics approval and consent to participate
: This observational study was approved by the ethics committee of the Department of Neurosurgery, Kasr Alainy Faculty of Medicine, Cairo University. All participants provided informed consent to participate in the study.
: Consent to publish has been obtained from the participants to report individual patient data.
: The authors declare that they have no competing interests.
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