1. Department of Neurosurgery, University of Baghdad, College of Medicine, Baghdad, Iraq,
2. Department of Biology, University of Al-Mustansiriyah, College of Sciences, Baghdad, Iraq,
3. Department of Neurosurgery, Azerbaijan Medical University, Baku, Azerbaijan, Iraq,
4. Department of Neurosurgery, Neurosurgical Teaching Hospital, Baghdad, Iraq,
5. Department of Neurosurgery, University of Cincinnati, Cincinnati, United States.