Local coil unit for a magnetic resonance apparatus

US7002347B2 · kind B2 · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Thorsten Feiweier · Peising, DE
• Razvan Lazar · Erlangen, DE
• Wolfgang Renz · Erlangen, DE
• Lothar Schön · Neunkirchen, DE

Key dates

• Filing date: Sep 29, 2004
• Grant date: Feb 21, 2006
• Expiry date: Sep 29, 2024

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R33/341
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A local coil unit for a magnetic resonance apparatus, which radiates a radio-frequency field into an examination subject, has a housing and at least a part of the housing is formed of an insulating dielectric material that passively compensates for an inhomogeneity in the high-frequency field in the subject. The material has a relative dielectric value εr of greater than 50, preferably greater than 100, and a dielectric loss factor tan δ of less than 2.5×10−2, preferably less than 1×10−3. In the dielectric material displacement currents are generated which create an additional magnetic field that compensates for the minima in the B1 field as a result of the eddy currents arising in the patient due to the radio-frequency radiation.