MR method with reduced motion artefacts

US5977769A · kind A · utility

Assignee

• U.S. Philips Corporation · US

Inventors

• Peter Bornert · Hamburg, DE
• Markus Weiger · Dietikon, CH
• Tobias Schaffter · Hamburg, DE

Key dates

• Filing date: Feb 7, 1997
• Grant date: Nov 2, 1999
• Expiry date: Feb 7, 2017

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R33/5676
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The invention relates to an MR method with reduced motion artefacts in which the displacement of a pulsating object, or of a part thereof, which is present in an examination zone is continuously measured relative to a reference position, and in which the reconstruction of an MR image utilizes exclusively MR signals acquired from the examination zone while the displacement from the reference position reaches or falls below a threshold value. This gating is enhanced in accordance with the invention in that prior to the acquisition of the MR signals there are generated phase encoding gradients k.sub.y) which act on the examination zone with different time integrals and that the threshold value (v.sub.s) can be varied in dependence on the respective phase encoding gradient (k.sub.y).