1. Department of Surgery, Leicester Royal Infirmary, Leicester LE2 7LX, UK
2. Department of Neurology, Leicester Royal Infirmary, Leicester LE2 7LX, UK
3. Department of Ophthalmology, Leicester Royal Infirmary, Leicester LE2 7LX, UK
4. Department of Radiology, Leicester Royal Infirmary, Leicester LE2 7LX, UK