Applications of high-resolution echoplanar spectroscopic imaging for structural imaging.

Echoplanar spectroscopic imaging (EPSI) was introduced as a fast alternative for spectroscopic imaging and has been recently implemented on clinical scanners. With further advances in gradient hardware and processing strategies, EPSI can be used to obtain spectroscopic images whose spatial resolution parallels that of conventional anatomic images within clinically acceptable acquisition time. The present work demonstrates that high-resolution EPSI can be used to derive structural images for applications in which spectroscopic information is beneficial. These applications are chemical shift (fat-water) imaging, narrow bandwidth imaging, and T2* mapping. In this paper, the EPSI sequence design and processing strategies are detailed and experimental results in normal volunteers are presented to illustrate the potential of using EPSI in imaging anatomic structures.