1. Department of Emergency Medicine, University of Witwatersrand, Johannesburg, South Africa;
2. Department of Neurology, University of Witwatersrand, Johannesburg, South Africa;
3. Department of Anaesthetics, University of Witwatersrand, Johannesburg, South Africa;
4. Department of Radiation Oncology, Wits University Donald Gordon Medical Centre, Parkstown, South Africa;
5. Department of Neurology, Chris Hani Baragwanath Hospital, Bertsham, South Africa