1. School of Physics, Clinical and Optometric Sciences, IEO Centre, Faculty of Science and Health, Technological University Dublin, D07 H6K8 Dublin, Ireland
2. Tissue Engineering Research Group (TERG), Department of Anatomy, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland
3. Medical Physics and Clinical Engineering Department, St Vincent’s Hospital, D04 T6F4 Dublin, Ireland
4. National Centre for Advanced Medical Imaging (CAMI), St James Hospital and with the School of Medicine, Trinity College Dublin, D08 NHY1 Dublin, Ireland
5. Department of Radiology, Mayo Clinic, Rochester, MN 55902, USA