1. Department of Neurosurgery, Prince Mohammed Bin Abdulaziz Hospital, Riyadh, Saudi Arabia
2. Department of Neurosurgery, Mansoura University, Mansoura, Egypt
3. Department of Diagnostic Radiology, Prince Mohammed Bin Abdulaziz Hospital, Riyadh, Saudi Arabia
4. Department of Biostatistics Epidemiology and Scientific computing, King Faisal Specialist Hospital and Research Hospital, Riyadh, Saudi Arabia