1. Section of Investigative Medicine and Endocrinology, Imperial College London , London W12 0NN , UK
2. Department of Endocrinology, Imperial College Healthcare NHS Trust , London W12 0HS , UK
3. Department of Endocrine and Thyroid Surgery, Imperial College Healthcare NHS Trust , London W12 0HS , UK
4. Imaging Department, Imperial College Healthcare NHS Trust , London W12 0HS , UK