Mehmet Turgut, MD, PhD, is an Assistant Professor in the Department of Neurosurgery at Adnan Menderes University School of Medicine, Aydin, Turkey. He graduated in Medicine at the Ege University School of Medicine, Izmir, Turkey and subsequently obtained his Specialization in Neurosurgery from Hacettepe University School of Medicine. In 2004 he was awarded his PhD by the Ege University Health Sciences Institute, Izmir, Turkey. Dr. Turgut has authored more than 250 publications, many of them in peer-reviewed journals and 3 books. He is a member of the editorial boards of various journals, including Journal of Spine, Central European Neurosurgery, Journal of Brachial Plexus and Peripheral Nerve Injury, and Journal of Spine and Neurosurgery. Ashok Kumar Mahapatra, BSc, MB BS, M.S. (Surgery), M.Ch. (Neurosurgery), is Professor of Neurosurgery at the Department of Neurosurgery, AIIMS, New Delhi, India and also Honorary Visiting Professor to CBMR Lucknow. He is a past Director of the Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow. Currently he is working as Director, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India since August 2012. Dr. Mahapatra is the recipient of numerous awards, and in 2004 he became a Fellow of the National Academy of Sciences. He has also held many important administrative appointments. Dr. Mahapatra has conducted research in various areas and is the author or editor of 13 books and more than 485 journal papers and 115 book chapters. Michael Peter Powell, MA (Oxon), MB BS (Lond), FRCS (Eng), FRCP (Lond), is a Consultant Neurosurgeon at the National Hospital for Neurology and Neurosurgery, London and Civilian Neurosurgeon to the Royal Air Force. Dr. Powell is an examiner for the Intercollegiate Board of Colleges of Surgeons in Neurosurgery and from 2008 to 2010 was Chairman of the Neurosurgery Specialty Advisory Committee of the Joint Committee onSurgical Training, Royal Colleges of Surgeons. Dr. Powell has held many further appointments as an honorary consultant neurosurgeon. He is the author of more than 60 articles in peer-reviewed journals and of the book The Management of Pituitary Tumours, published in 2004. Natarajan Muthukumar, MB BS, M.Ch. (Neurosurgery), is Professor and Head of the Department of Neurosurgery at Madurai Medical College, Madurai, India. Dr. Muthukumar is Associate Editor of Neurology India, the official journal of the Neurological Society of India, and a referee for a number of other leading journals. He has been the author of 76 publications, most of them in peer-reviewed journals. His research interests include in particular congenital malformations of the nervous system, spinal surgery, and neurotrauma.