Patent · US Expired

MRI apparatus

US7180293B2 · kind B2 · utility

1Cited by
8References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 8, 2005
Grant dateFeb 20, 2007
Priority date
Expiry dateNov 8, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R33/389
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

For the purpose of providing an MRI apparatus which gives rise to no phase deviation due to frequency alteration of the RF magnetic field and signals for detection use, the MRI apparatus includes: signal collecting means which detects and collects magnetic resonance signals generated by applying a magnetostatic field, a gradient magnetic field and an RF magnetic field onto an object; frequency altering means which alters the frequency of the RF magnetic field and the frequency of signals for detection use in accordance with change in the Larmor frequency with time; and image reconstructing means which reconstructs an image on the basis of the collected signals, and further comprises: phase control means which sets as the phase at the time of starting detection of signals for detection use a phase Δθ given by a relational expression Δθ=2π·Δf·T using the difference Δf between the frequency altered by the frequency altering means and a reference frequency, and a time period T from the start of applying the RF magnetic field to the start of detection of magnetic resonance signals.

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