Patent · US Expired

Magnetic resonance imaging

US7230424B1 · kind B1 · utility

11Cited by
8References
25Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 17, 2005
Grant dateJun 12, 2007
Priority date
Expiry dateJul 9, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R33/56563
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Through advancing the phase of radio frequency (RF) excitation with each phase-encoding level, a method and apparatus increases the effectiveness of a Magnetic Resonance Imaging (MRI) device by correcting for main magnetic field inhomogeneities without noticeably decreasing the signal-to-noise ratio. The present invention also increases the effectiveness of fast imaging with steady precession (FISP) scans and allows FISP scans to image multiple slices. In an MRI device, a patient is subjected to a constant magnetic field, and RF pulses are used to excite the nuclei in the patient's body. The nuclei release a corresponding RF signal as the nuclei relax, which can be measured and mapped into a visual display. The RF pulses used to excite the nuclei in the body cooperate with a slice select gradient and a phase-encoding gradient. When the RF pulse is phase shifted with each phase-encoding gradient level, improved signal-to-noise ratios are observed.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.