title: Preface.
authors.affiliation: Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, 110029, India.
authors.forename: Rakesh
authors.initials: R
authors.lastname: Kumar
authors.affiliation: Radiation Medicine Centre, BARC, Mumbai, India.
authors.forename: Sandip
authors.initials: S
authors.lastname: Basu
authors.affiliation: Nuclear Medicine Section, Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, USA.
authors.forename: Abass
authors.initials: A
authors.lastname: Alavi