MRI RF pulse sequence for multidimensional outer volume suppression

US10690739B2 · kind B2 · utility

Assignee

• The Board of Trustees of the Leland Stanford Junior University · US

Inventors

• David Y. Zeng · San Francisco, US
• Dwight G. Nishimura · Palo Alto, US

Key dates

• Filing date: Apr 7, 2017
• Grant date: Jun 23, 2020
• Expiry date: Nov 16, 2038

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R33/5617
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A magnetic resonance imaging (MRI) techniques uses a T2-preparation outer volume suppression (OVS) pulse sequence to reduce the longitudinal magnetization outside a region of interest. A region is excited that includes the region of interest, radiofrequency (RF) signals are detected, and MRI images generated from the RF detected signals. The T2-preparation OVS pulse sequence includes, sequentially: a first tip-down excitation pulse, a first refocusing excitation pulse, a first tip-up excitation pulse that is selective spatially and/or spectrally, a second tip-down excitation pulse that is 180° out of phase with respect to the first tip-down excitation pulse, a second refocusing excitation pulse, and a second tip-up excitation pulse that is selective spatially and/or spectrally. Alternatively, the first tip-down excitation pulse is selective spatially and/or spectrally instead of the first tip-up excitation pulse, and the second tip-down excitation pulse is selective spatially and/or spectrally instead of the second tip-up excitation pulse.