Abstract: A radio frequency coil for magnetic resonance imaging includes an active coil member (70, 701, 170, 270) that defines an imaging volume. The active coil member has a first open end (74) with a first cross-sectional dimension (dactive). A shield coil member (72, 721, 722, 723, 724, 725, 172, 1722, 272) substantially surrounds the active coil member. The shield coil member has a constricted open end (88) arranged proximate to the first open end of the active coil member with a constricted cross-sectional dimension (dconst) that is less than the cross-sectional dimension (dShieid) of the shield coil member. In some embodiments, the radio frequency coil further includes an outer shield coil member (100) that is substantially larger than the shield coil member (72, 721, 722, 723, 724, 725, 172, 1722, 272), and surrounds both the active coil member and the shield coil member.

Abstract: A radio frequency coil assembly (32) for magnetic resonance imaging includes a coil array portion (60, 60?, 88) and a TEM coil portion (62, 62?). The coil array portion includes a plurality of decoupled coil loops (70, 70?, 90). The TEM coil portion includes a plurality of rods (72, 72?) coupled with a radio frequency screen (34, 34?). Each rod of the TEM coil portion is electromagnetically orthogonal to a corresponding coil loop of the coil array portion.

Abstract: A radio frequency coil system (38) for magnetic resonance imaging includes a plurality of parallel spaced apart rungs (60) which each includes rung capacitors (68). An end cap (64) is disposed at a closed end (66) of the coil system (38). An RF shield (62) is connected to the end cap (64) and surrounds the rungs (60), extending in a direction substantially parallel to rungs (60). The RF coil system (38) may be used as birdcage, TEM, hybrid, combination birdcage and TEM, or other.

Abstract: A magnetic resonance imaging system includes main magnet (20) that produces a substantially spatially and temporally constant main magnetic field within a field of view. Magnetic field gradient coils (30) impose selected magnetic field gradients on the main magnetic field within the field of view. At least one radio frequency coil (44, 44?, 44?, 144, 154) is arranged to detect a magnetic resonance signal induced by an applied radio frequency pulse. The at least one radio frequency coil includes a radio frequency antenna (90) and electronics module (78, 78?) disposed on a substrate (72). The electronics are electrically connected with the radio frequency antenna (90). The electronics are mounted in a centered region (96) surrounded by the radio frequency antenna.

Abstract: A radio frequency apparatus for at least one of (i) receiving and (ii) exciting a magnetic resonance signal includes an item of clothing (102, 202). The item of clothing includes one or more layers (110, 112, 120, 122, 300, 402) that are stretchable to comport with differently sized and shaped imaging subjects. A plurality of radio frequency coils (104, 114, 204, 206, 208, 302, 404) are attached to one or more layers of the item of clothing. The coils are relatively movable with respect to one another responsive to stretching of the stretchable item of clothing. The one or more layers of the item of clothing include an anti-microbial agent (92, 92?, 94?) disposed on or incorporated into at least one layer.

Abstract: A radio frequency coil for magnetic resonance imaging includes an active coil member (70, 701, 170, 270) that defines an imaging volume. The active coil member has a first open end (74) with a first cross-sectional dimension (dactive). A shield coil member (72, 721, 722, 723, 724, 725, 172, 1722, 272) substantially surrounds the active coil member. The shield coil member has a constricted open end (88) arranged proximate to the first open end of the active coil member with a constricted cross-sectional dimension (dconst) that is less than the cross-sectional dimension (dShieid) of the shield coil member In some embodiments, the radio frequency coil further includes an outer shield coil member (100) that is substantially larger than the shield coil member (72, 721, 722, 723, 724, 725, 172, 1722, 272), and surrounds both the active coil member and the shield coil member.

Abstract: A radio frequency coil assembly (32) for magnetic resonance imaging includes a coil array portion (60, 60?, 88) and a TEM coil portion (62, 62?). The coil array portion includes a plurality of decoupled coil loops (70, 70?, 90). The TEM coil portion includes a plurality of rods (72, 72?) coupled with a radio frequency screen (34, 34?). Each rod of the TEM coil portion is electromagnetically orthogonal to a corresponding coil loop of the coil array portion.

Abstract: A radio frequency coil system (38) for magnetic resonance imaging includes a plurality of parallel spaced apart rungs (60) which each includes rung capacitors (68). An end cap (64) is disposed at a closed end (66) of the coil system (38). An RF shield (62) is connected to the end cap (64) and surrounds the rungs (60), extending in a direction substantially parallel to rungs (60). The RF coil system (38) may be used as birdcage, TEM, hybrid, combination birdcage and TEM, or other.

Abstract: A radio frequency coil for a magnetic resonance imaging system includes a birdcage section having a plurality of parallel spaced apart conductors and one or more cross or end conductors aligned generally transverse to the spaced apart conductors, and a TEM section having a plurality of parallel spaced apart conductors and a radio frequency screen. The birdcage section and the TEM section resonate at a birdcage resonant frequency and a TEM resonant frequency, respectively. The birdcage section and the TEM section are relatively disposed with the parallel spaced apart conductors of each section aligned and define a subject receiving region.

Abstract: The invention relates to an MR method in which the nuclear magnetization is enhanced under the influence of a first steady magnetic field and a second steady magnetic field acts on the nuclei previously influenced by the first magnetic field. According to the invention, the two magnetic fields overlap in time and enclose an angle other than 0° relative to one another, the angle preferably amounting to 90°. The enhanced nuclear magnetization is then sustained after the activation of the first steady magnetic field while the direction of the nuclear magnetization is determined by the second steady magnetic field. The use of two mutually perpendicular magnetic fields is advantageous notably for Overhauser imaging methods, because it enables the use of mutually perpendicular RF fields for the ESR saturation and the MR excitation, thus uncoupling the coils generating such RF fields from one another.

Abstract: An MR apparatus which includes a cylindrical coil system and a surface coil system. In order to form a coherent MR image of an as large as possible examination zone by means of an MR apparatus, without necessitating the use of a larger number of receiving channels with respect to a conventional MR apparatus, the cylindrical coil system, for example a bird-cage resonator, and the surface coil system, for example a quadrature coil system, are arranged to overlap and the magnitude of the region of overlap can be varied in order to reduce mutual coupling.

Abstract: As rf quadrature coil system for a magnetic resonance examination apparatus, comprises two similar rf coils connected to an rf receiver and/or an rf transmitter and arranged so as to be offset 90.degree. with respect to one another. Each rf coil comprises several turns which are situated in mutually parallel planes. The planes of the turns of one rf coil extend perpendicular to the planes of the turns of the other rf coil. The quadrature coil system can be used in magnetic resonance examination apparatus in which the uniform, steady magnetic field required for the examination extends perpendicular to the longitudinal axis of the patient to be examined.

Abstract: A magnetic resonance examination apparatus includes a coil system (10) for receiving spin resonance signals generated in an examination zone, and a processing unit remote from the examination zone for processing the signals received in the coil system. Disturbing effects are liable to occur when a coil system is connected to the processing unit via a cable. These disturbing effects are avoided in that in the direct vicinity of the coil system there is arranged a transmitter for transmitting the spin resonance signals. This transmitter cooperates in a wireless fashion with a receiver to which the processing unit is connected.

Abstract: The invention relates to a magnetic resonance imaging apparatus comprising an RF coil. A high Q and a high sensitivity are achieved in that the coil consists of separate resonators which are tuned to the same resonance frequency and which are inductively coupled to one another but not conductively connected to one another.

Abstract: An MR examination apparatus has a quadrature coil arrangement which consists of two coil systems and a circuit for decoupling the two coil systems. In such an MR examination apparatus the decoupling between the coil systems is improved in that the circuit comprises a variable capacitor which connects one coil system to the other.

Abstract: An rf quadrature coil system comprises two coil pairs, each of which consists of two coils; only one of the two coils of each pair is connected to an rf transmitter or rf receiver. High-quality factors and a high homogeneity of the rf field are thus obtained.