1. Division of Neurosurgery, Department of Surgery, College of Medicine, King Saud University, Riyadh, Saudi Arabia;
2. Department of Neurosurgery, King Fahad Medical City, Riyadh, Saudi Arabia;
3. Division of Neurosurgery, Department of Neuroscience, King Faisal Hospital and Research Center, Riyadh, Saudi Arabia;
4. College of Medicine, Prince Sattam Bin Abdulaziz University, Riyadh, Saudi Arabia;
5. Division of Neurosurgery, Department of Surgery, King Saud University Medical City, Riyadh, Saudi Arabia