[1] King Saud Univ, Coll Med, Div Neurosurg, Riyadh 11472, Saudi Arabia
[2] King Saud Univ, King Khalid Univ Hosp, Riyadh 11472, Saudi Arabia
[3] King Saud Univ, Coll Med, Dept Anesthesia, Riyadh 11472, Saudi Arabia
[4] Taibah Univ, Div Neurosurg, Al Madinah Al Munawarah, Saudi Arabia