1. Department of Diagnostic and Interventional Imaging, University of Texas Health Science Center at Houston, Houston, Texas.
2. Department of Physical Medicine and Rehabilitation, Baylor College of Medicine, Houston, Texas.
3. Department of Radiology, Baylor College of Medicine, Houston, Texas.
4. Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas.
5. Department of Neurosurgery, Virginia Commonwealth University, Richmond, Virginia.
6. Department of Neurosurgery, Baylor College of Medicine, Houston, Texas.
7. Department of Emergency Medicine, University of Texas Health Science Center at Houston, Houston, Texas.