Apparatus for the identification of nuclear magnetic spectra from spatially selectable regions of an examination subject

US4801884A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Arnulf Oppelt · Spardorf, DE
• Uwe Klose · Braunschweig, DE
• Ralf Ladebeck · Erlangen, DE
• Dietmar Hentschel · Vacha, DE

Key dates

• Filing date: Feb 1, 1988
• Grant date: Jan 31, 1989
• Expiry date: Feb 1, 2008

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R33/482
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An apparatus for identifying nuclear magnetic spectra from spatially selectable regions of an examination subject supplies pulse signals to the examination subject in the following sequence. A first, non-selective 90.degree. RF pulse is supplied to the patient so that the magnetization of the examination subject is oriented out of the z-direction into an x-y plane perpendicular thereto. A first, selective 180.degree. RF pulse is then supplied simultaneously with a first magnetic gradient G.sub.z which effects a dephasing of the spins outside of a first, selected slice S.sub.1. A second, selective 180.degree. RF pulse is then supplied simultaneously with a second magnetic gradient G.sub.x disposed perpendicularly to the first magnetic gradient. The second magnetic gradient effects a dephasing of the spins outside of a second selected slice S.sub.2. A second, selective 90.degree. RF pulse is then supplied simultaneously with a third magnetic gradient G.sub.y, which is disposed perpendicularly relative to the first and second magnetic gradients. A third 90.degree. RF pulse is then supplied, and the signal emitted by the examination subject in response thereto is evaluated.