1. Department of Neurology, Section, Critical Care Medicine, Philadelphia, PA, USA.
2. Department of Medicine, Drexel University College of Medicine, Philadelphia, PA, USA.
3. Department of Neurosurgery, Drexel University College of Medicine, Philadelphia, PA, USA.
4. Department of Surgery, Drexel University College of Medicine, Philadelphia, PA, USA.
5. Department of Pathology, Drexel University College of Medicine, Philadelphia, PA, USA.