1. Departments of Neurosurgery, School of Clinical Sciences, University of Natal Medical School and Wentworth Hospital, Durban, South Africa
2. Departments of Hematology, School of Clinical Sciences, University of Natal Medical School and Wentworth Hospital, Durban, South Africa
3. Departments of Neurology, School of Clinical Sciences, University of Natal Medical School and Wentworth Hospital, Durban, South Africa