This book presents an extensive insight into various applications of ultrasonography in medical science and associated domains. Compiled with contributions from international experts, it offers the readers with current information and future research pathways of diagnostic and therapeutic ultrasound and spectroscopy. Major topics comprise of Duplex ultrasound, transcranial color Duplex, MRA guided Doppler ultrasonography and near-infrared spectroscopy. The applications of ultrasound for the discovery of intra-cardiac and intra-pulmonary shunts have also been explained along with its utility for the assessment of gastric regulation and emptying in the book. New directions in the use and application of transcranial and color Duplex ultrasound have also been presented, along with the use of ultrasound and arterial stiffness for measuring human vascular health and circulatory control.