Abstract: The present disclosure is directed to a balun package comprising a set of inductive baluns for a magnetic resonance imaging (MRI) radio frequency (RF) coil. A first resonant circuit and a second resonant circuit each comprise an inductor. A first decoupling circuit leg is between and shared by the first and second resonant circuits and includes one or more decoupling inductors and/or one or more decoupling capacitors. A first cable bundle is wound to form the inductor of the first resonant circuit or is otherwise spaced from and inductively coupled to the inductor of the first resonant circuit.

Abstract: In some embodiments, the present disclosure relates to a multi-turn (MT) birdcage magnetic resonance imaging (MRI) radio-frequency (RF) coil. The MT birdcage MRI RF coil includes a first conductive ring, a second conductive ring, and a plurality of conductive rungs. Each of the plurality of conductive rungs includes a first end coupled to the first conductive ring, and a second end coupled to the second conductive ring. At least one of the first conductive ring and the second conductive ring includes more than one turn. The first conductive ring, the second conductive ring, and the plurality of conductive rungs form a plurality of meshes.

Abstract: A magnetic resonance imaging (MRI) system can include a gapped degenerate birdcage magnetic resonance imaging (MRI) radio frequency (RF) coil. The gapped degenerate birdcage MRI RF coil is tuned to a degenerate mode and comprises a row of RF coil elements and a mechanical gap. The RF coil elements may also be referred to as channels or meshes. The row extends circumferentially around an axis of a cylindrical-like former, and mechanical gap separates a pair of directly neighboring RF coil elements in the row. A transformer, a partial overlap, or the like minimizes inductive coupling between the pair of directly neighboring RF coil elements.

Abstract: In some embodiments, the present disclosure relates to a radio frequency (RF) surface coil for a magnetic resonance imaging (MRI) system. The RF surface coil includes a rigid lower member, at least one flexible upper member mechanically coupled to the rigid lower member, and one or more RF coil elements housed by the rigid lower member and the at least one flexible upper member. The at least one flexible upper member is dimensioned and manipulable to substantially conform the one or more RF coil elements to a portion of a patient anatomy to be imaged by the MRI system.

Abstract: The present disclosure relates to a magnetic resonance imaging (MRI) radio frequency (RF) array coil that includes first and second physical RF coils inductively coupled. A first matching circuit and a second matching circuit are coupled to the first physical RF coil and the second physical RF coil, respectively, and are coupled in a parallel configuration at a first RF port. A third matching circuit and a fourth matching circuit are coupled to the first physical RF coil and the second physical RF coil, respectively, and are coupled in an anti-parallel configuration at a second RF port. A first logical RF coil is formed by the first and second physical RF coils and the first and second matching circuits. A second logical RF coil, which is decoupled from the first logical RF coil, is formed by the first and second physical RF coils and the third and fourth matching circuits.

Abstract: In some embodiments, the present disclosure relates to a flexible magnetic resonance imaging (MRI) radio frequency (RF) array coil configured to operate in at least one of a transmit (Tx) mode or a receive (Rx) mode. The MRI RF array coil includes a first row of saddle coil elements. At least a first saddle coil element and a second saddle coil element are in the first row. The first and second saddle coil elements partially overlap with one another. Each of the first and second saddle coil elements include a left loop and a right loop that is coupled to the left loop by two connection segments.

Abstract: The present disclosure relates to a magnetic resonance imaging (MRI) radio frequency (RF) array coil that includes first and second physical RF coils inductively coupled. A first matching circuit and a second matching circuit are coupled to the first physical RF coil and the second physical RF coil, respectively, and are coupled in a parallel configuration at a first RF port. A third matching circuit and a fourth matching circuit are coupled to the first physical RF coil and the second physical RF coil, respectively, and are coupled in an anti-parallel configuration at a second RF port. A first logical RF coil is formed by the first and second physical RF coils and the first and second matching circuits. A second logical RF coil, which is decoupled from the first logical RF coil, is formed by the first and second physical RF coils and the third and fourth matching circuits.

Abstract: Embodiments relate to integrated MRI (Magnetic Resonance Imaging) coil arrays that can be stored within a patient table when not in use. One example embodiment comprises a coil array comprising: at least one flat spine-like coil array arranged within a patient table of a MRI system; and flexible coil array(s) configured to be in a stored position within the patient table, wherein, in the stored position, the flexible coil array(s) are one of within or under the at least one flat spine-like rigid coil array, wherein the flexible coil array(s) are further configured to be in an extended position, wherein, in the extended position, the flexible coil array(s) is configured to be extracted from the patient table and to wrap around at least one anatomical region of a patient on the patient table to facilitate MRI of the at least one anatomical region.

Abstract: Embodiments relate to MRI RF multi-tune coil elements, arrays, and MRI systems comprising such elements. One example embodiment comprises: a LC coil comprising one or more matching points; and two or more matching branches, each of which connected to the LC coil at matching point of the one or more matching points that is associated with that matching branch, wherein each matching branch comprises an associated set of one or more RF traps configured to block each frequency of two or more frequencies other than a frequency associated with that matching branch, and wherein each matching branch is configured to match to an associated predetermined impedance at the frequency associated with that matching branch.

Abstract: Various embodiments of the present disclosure are directed towards a magnetic resonance imaging (MRI) radio frequency (RF) coil array configured to operate in at least one of a transmit mode or a receive mode on a cylindrical former. The MRI RF coil array includes at first row of RF coil elements. Each row of RF coil elements includes at least three RF coil elements that circumferentially surround a cylindrical axis. The MRI RF coil array also includes a first birdcage coil that circumferentially surrounds the first row of RF coil elements. Each RF coil element of the first row is configured to inductively couple to the first birdcage coil and to each other RF coil elements. The first birdcage coil has an impedance configured to negate inductive coupling between the RF coil elements of the first row.

Abstract: Various embodiments of the present disclosure are directed towards a magnetic resonance imaging (MRI) radio frequency (RF) coil configured to operate in at least one of a transmit mode or a receive mode. A first birdcage coil includes a pair of first-birdcage end rings and at least four first-birdcage rungs circumferentially arranged along the first-birdcage end rings. A second birdcage coil including a pair of second-birdcage end rings and at least four second-birdcage rungs circumferentially arranged along the second-birdcage end rings. The first and second birdcage coils neighbor and are spaced by a first non-zero distance along an axis. The axis is surrounded by the first-birdcage end rings and the second-birdcage end rings, and the first non-zero distance is greater than individual lengths of the first and second birdcage coils along the axis.

Abstract: Various embodiments of the present disclosure are directed towards a magnetic resonance imaging (MRI) head coil comprising an open shield. A transmit coil surrounds a phased array receive coil and comprises a resonant birdcage structure. The resonant birdcage structure comprises multiple transmit rungs spaced in a first closed path, and inter-rung spacing at one or more first locations on the first closed path is greater than at a remainder of the first closed path. The open shield surrounds the transmit coil and comprises a non-resonant birdcage structure. The non-resonant birdcage structure comprises multiple shield rungs spaced in a second closed path. The shield rungs are elongated in parallel with the transmit rungs, and inter-rung spacing at one or more second locations on the second closed path is greater than at a remainder of the second closed path. Further, the second location(s) respectively and radially border the first location(s).

Abstract: Embodiments relate to MRI coils with a reduced number of baluns. One example embodiment is a MRI coil comprising: a plurality of coil elements in one or more groups of coil elements, wherein each group of coil elements comprises at least two coil elements and a shared trace comprising portions of associated traces of each coil element of that group RF shorted together, and wherein, for each coil element of that group, the shared trace of the group is RF shorted to a shield of an associated coaxial cable for that coil element; and one or more baluns, wherein, for each group of coil elements, at least one balun of the one or more baluns is configured to mitigate leakage current on the coaxial cable of each coil element of that group of coil elements.

Abstract: Various embodiments of the present disclosure are directed towards a radio frequency (RF) coil comprising a first combination coil and a second combination coil. The first combination coil comprises a first resonant coil and a first resonant shield coupled inductively or by a capacitor, and the first combination coil has a first resonant frequency and a second resonant frequency. The second combination coil comprises a second resonant coil and a second resonant shield coupled inductively or by a capacitor, and the second combination coil has a third resonant frequency and a fourth resonant frequency. The first and second resonant coils are inductively coupled to each other and respectively to the second and first resonant shields. The first and third resonant working frequencies are the same, and the second and fourth resonant isolation frequencies are such that inductive coupling between the first and second resonant coils is negated.

Abstract: In some embodiments, the present disclosure relates to a flexible magnetic resonance imaging (MRI) radio frequency (RF) array coil configured to operate in at least one of a transmit (Tx) mode or a receive (Rx) mode. The MRI RF array coil includes a first row of saddle coil elements. At least a first saddle coil element and a second saddle coil element are in the first row. The first and second saddle coil elements partially overlap with one another. Each of the first and second saddle coil elements include a left loop and a right loop that is coupled to the left loop by two connection segments.

Abstract: Various embodiments of the present disclosure are directed towards a magnetic resonance imaging (MRI) radio frequency (RF) coil configured to operate in at least one of a transmit mode or a receive mode. A first birdcage coil includes a pair of first-birdcage end rings and at least four first-birdcage rungs circumferentially arranged along the first-birdcage end rings. A second birdcage coil including a pair of second-birdcage end rings and at least four second-birdcage rungs circumferentially arranged along the second-birdcage end rings. The first and second birdcage coils neighbor and are spaced by a first non-zero distance along an axis. The axis is surrounded by the first-birdcage end rings and the second-birdcage end rings, and the first non-zero distance is greater than individual lengths of the first and second birdcage coils along the axis.

Abstract: Embodiments relate to cylindrical MRI coils with at least one row as a birdcage row in a transmit mode. One example embodiment is a MRI Radio Frequency (RF) coil array comprising two or more rows of four or more RF coil elements each. Each of the RF coil elements can be configured to resonate at a working frequency of the coil array in a receive mode. At least one of the rows can be configured as a birdcage coil in the transmit mode, and the two or more rows can inductively couple together such that all the two or more rows can resonate together in the transmit mode at the working frequency.

Abstract: Embodiments relate to cylindrical MRI coil arrays with reduced coupling between coil elements. One example embodiment comprises two or more rows, wherein each row comprises at least three RF coil elements of that row enclosing a cylindrical axis; and a ring comprising an associated portion of each RF coil element of a first row and a second row electrically connected together, wherein the associated portion of each RF coil element of the first row and of each RF coil element of the second row comprises an associated capacitor of that RF coil element, and wherein the associated capacitor of that RF coil element is configured to reduce coupling among the RF coil elements of the first row and the RF coil elements of the second row.

Abstract: A single-layer magnetic resonance imaging (MRI) radio frequency (RF) coil element configured to operate in a transmit (Tx) mode and a receive (Rx) mode, the coil element comprising: an LC coil and a failsafe circuit electrically connected with the LC coil, where the LC coil, upon resonating with a primary coil of an MRI system, generates a local amplified Tx field based on an induced current generated in the LC coil by inductive coupling between the LC coil and the primary coil, where the failsafe circuit provides, upon injection of a forward DC bias current into the failsafe circuit, a first impedance, and upon the absence of the forward DC bias current, a second, higher impedance; where the failsafe circuit, upon the single-layer MRI RF coil array element being disconnected from an MRI system, provides the second, higher impedance, and reduces the magnitude of the induced current.

Abstract: A magnetic resonance imaging (MRI) radio frequency (RF) coil array configured to operate in a transmit (Tx) mode or in a receive (Rx) mode, comprising: a plurality of rows configured in an anatomy-specific shape, a row including a plurality of RF coil elements, an RF coil element including an LC coil and a magnitude/phase control component, where the LC coil, upon resonating with a primary coil at the working frequency of the primary coil, generates a local amplified Tx field based on an induced current in the LC coil, where a magnitude or a phase of the induced current is independently adjustable, where the magnitude/phase control component is configured to adjust the magnitude or phase of the induced current, and where the magnitude or phase of the induced current of a first RF coil element is independently adjustable from that of a second, different RF coil element.