DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Priority
Receipt is acknowledged of certified copies of papers submitted under 35 U.S.C. 119(a)-(d), which papers have been placed of record in the file.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 04/10/2025. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
Claim Rejections - 35 USC § 112
4. The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 16 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 16 recites the limitation “the first reversed superconducting coil” in line 3. There is insufficient antecedent basis for this limitation in the claim.
Claim Rejections - 35 USC § 102
7. The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1-5 and 11-12 and 16-17 are rejected under 35 U.S.C. 102 as being anticipated by Westphal (U.S. Patent No. 5,545,997).
Regarding claim 1, Westphal discloses "A magnet arrangement for a magnetic resonance imaging device, comprising:" a nuclear magnetic resonance tomography apparatus having a superconducting main field magnet for producing a static homogeneous magnetic field in an investigational volume (Fig. 4; col. 1, lines 8-18).
Westphal discloses "a main magnet including a plurality of superconducting coils, a reversed superconducting coil, and a ferromagnetic element," wherein the magnet includes outer field coils 1a, 1b, inner field coils 2a, 2b, and superconducting correction coils C1 through Cp. Each correction coil comprises partial coils C1 i, C1 a through Cpi, Cpa driven with oppositely directed currents during operation. Westphal further provides ferromagnetic homogeneity elements 20 (Fig. 4; col. 7, line 54-col. 8, line 7; col. 8, lines 25-52).
Westphal discloses "wherein the reversed superconducting coil is arranged between two of the plurality of superconducting coils, and" wherein, as shown in Figure 4, correction coil partial coil C2i, having a current direction opposite to its corresponding partial coil, is positioned axially between superconducting coils 1 b and 2b (Fig. 4; col. 7, line 54--col. 8, line 7).
Westphal further discloses "wherein the ferromagnetic element is arranged between the reversed superconducting coil and one of the plurality of superconducting coils." As shown in the upper right portion of Figure 4, a ferromagnetic homogeneity element 20 is positioned axially between correction coil partial coils C2i and C2a. Westphal identifies elements 20 as ferromagnetic homogeneity elements and discloses positioning the elements at selected locations along the z axis for compensating field distortions (Fig. 4; col. 8, lines 25-52).
Regarding claim 2, Westphal further discloses "wherein the one of the plurality of
superconducting coils comprises an end coil of the main magnet" (Fig. 4, C2a; col. 7,
lines 54-65).
Regarding claim 4, Westphal further discloses "wherein the ferromagnetic element is arranged as a spacer between the reversed superconducting coil and the one of the plurality of superconducting coils."
As shown in the upper-right portion of Figure 4, ferromagnetic homogeneity element 20 is positioned in the space between superconducting correction coil partial coils C2i and C2a.
Westphal identifies elements 20 as ferromagnetic homogeneity elements and discloses positioning the elements at selected axial locations for correcting magnetic field distortions (Fig. 4; col. 8, lines 25-52). Thus, Figure 4 shows ferromagnetic element 20 occupying the intervening space between C2i and C2a, corresponding to the claimed ferromagnetic element "arranged as a spacer between" the reversed superconducting coil and the one of the plurality of superconducting coils.
Regarding claim 8, Westphal further discloses "wherein the ferromagnetic element comprises or consists of a high permeability material."
Westphal expressly identifies elements 20 as ferromagnetic homogeneity elements used for correcting magnetic field distortions and improving homogeneity of the magnetic field. A ferromagnetic material inherently possesses significant magnetic permeability; therefore, Westphal's ferromagnetic elements 20 necessarily comprise a high permeability material.
Regarding claim 12, Westphal further discloses "wherein the one of the plurality of superconducting coils comprises an end coil."
Westphal discloses outer field coils 1 a and 1 b positioned on opposite sides of the middle plane E, with the superconducting coil arrangement extending axially along the magnet. As shown in Figure 4, coil 1 b is positioned at the axial end region of the superconducting main field coil arrangement and thus comprises an end coil (Fig. 4; col. 7, lines 48-65).
Regarding claim 16, Westphal further discloses "wherein the reversed superconducting coil comprises a first reversed superconducting coil from among a plurality of reversed superconducting coils comprising the first superconducting coil and a second reversed superconducting coil, and further comprising: a first ferromagnetic element; and a second ferromagnetic element."
Westphal discloses four superconducting correction coils C1 through C4, each comprising partial coils driven with oppositely directed currents during operation. Thus, Westphal provides a plurality of superconducting coil portions having current directions opposite to the other superconducting coils. Westphal also discloses a plurality of ferromagnetic homogeneity elements 20 positioned at various locations along the z axis (Fig. 4; col. 7, line 54 col. 8). Westphal further discloses "wherein the first ferromagnetic element is arranged between the first reversed superconducting coil and the one of the plurality of superconducting coils, and wherein the second ferromagnetic element is arranged between the second reversed superconducting coil and another one of the one of the plurality of superconducting coils."
As shown in Figure 4, Westphal provides the superconducting correction coil arrangement symmetrically on opposite sides of middle plane E, and provides multiple ferromagnetic homogeneity elements 20 at axial locations along the bore. The same arrangement shown on the right side of Figure 4 is provided on the opposite side of the middle plane, thereby providing respective ferromagnetic elements positioned between respective oppositely driven superconducting coil portions and superconducting coils on the two sides of the magnet (Fig. 4; col. 7, line 54-col. 8).
Regarding claim 17, the structure recited is intrinsic to the method recited in claim 1, as disclosed by Westphal (U.S. Patent No. 5,545,997) as the recited structure will be used during the normal operation of the method, as discussed above with regard to claim. Westphal further teaches "an imaging region configured to receive an object" by disclosing an NMR tomography apparatus having an investigational volume Vin which the magnetic field is generated and a patient is examined (Fig. 2; col. 1, lines 8-18, 54-65; col. 6, lines 26- 34). Westphal further teaches "a controller configured to control the magnetic resonance device to acquire, using magnetic fields generated via the main magnet, magnetic resonance data of the object positioned within the imaging region." Westphal expressly discloses an NMR tomography apparatus that generates a static homogeneous magnetic field in the investigational volume and produces NMR slice images of the patient. Acquisition and processing of magnetic resonance data using the generated magnetic field necessarily occurs in operation of the disclosed NMR tomography apparatus to produce the disclosed NMR slice images (col. 1, lines -
18; col. 1, line 66-col. 2, line 4).
Claim Rejections - 35 USC § 103
8. The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102 of this title, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over Westphal (U.S. Patent No. 5,545,997)
Regarding claim 3, Westphal does not expressly teach "wherein the ferromagnetic element is arranged directly adjacent to the reversed superconducting coil."
Westphal, however, teaches ferromagnetic homogeneity elements 20 positioned at different locations along the z axis and teaches experimentally determining the distribution and locations of the ferromagnetic elements to eliminate magnetic field distortions (Fig. 4; col. 8, lines 25-52).
It would have been obvious to one of ordinary skill in the art to arrange the ferromagnetic element directly adjacent to the reversed superconducting coil because Westphal teaches selecting the location of the ferromagnetic elements according to the magnetic field distortion to be corrected. Such positioning would have been a predictable variation of the disclosed placement of the ferromagnetic elements for the purpose taught by Westphal of compensating magnetic field distortions and improving field homogeneity.
Claims 5-7 are rejected under 35 U.S.C. 103 as being unpatentable over Westphal (U.S. Patent No. 5,545,997) in view of Cao (CN210323334U).
Regarding claim 5, Westphal does not expressly teach "wherein the ferromagnetic element comprises the shape of a ring."
CAO in a relevant art, however, teaches using ferromagnetic material in a magnetic resonance imaging device to change the local magnetic field distribution and improve magnetic field uniformity, and teaches that the ferromagnetic material can be formed as a coil ([0030]). CAO further teaches first coil 31 extending as a closed curve around the axis of superconducting magnet 1 and expressly teaches that first coil 31 "is in the shape of a ring" ([0031]; Fig. 2).
It would have been obvious to one of ordinary skill in the art to provide the ferromagnetic element of Westphal in the ring shape taught by CAO to provide ferromagnetic
material circumferentially about the magnet axis for adjusting the magnetic field distribution and improving magnetic field uniformity,
Regarding claim 6, Westphal does not expressly teach "wherein the main magnet and the ferromagnetic element are cylindrical and coaxially arranged."
CAO in a relevant art, however, teaches superconducting magnet 1 having a cylindrical configuration and gradient coil assembly 2 being cylindrical and coaxial with superconducting magnet 1 ([0029]; Fig. 1). CAO further teaches that ferromagnetic material may be disposed on the inner wall of superconducting magnet 1 or the outer wall of gradient coil assembly 2, and teaches first coil 31 as a closed ring extending around the axis of superconducting magnet 1 ([0030]-[0031]; Fig. 2).
It would have been obvious to one of ordinary skill in the art to provide the ferromagnetic element of Westphal in the cylindrical, coaxial arrangement taught by CAO, such
that the ferromagnetic element extends circumferentially about and shares the axis of the
cylindrical main magnet, for adjusting the magnetic field distribution and improving
magnetic field uniformity as taught by CAO.
Regarding claim 7, Westphal does not expressly teach "wherein a projected cross-section of the ferromagnetic element overlaps with a projected cross-section of the reversed superconducting coil."
CAO in a relevant art, however, teaches arranging the first, second, and third coil groups so that they overlap each other along the radial direction of superconducting magnet 1. CAO
further teaches that these coil groups may be stacked on the outer wall of gradient coil
assembly 2, with the second coil group superimposed on the first coil group and the third coil
group superimposed on the second coil group ([0035]; Fig. 2).
It would have been obvious to one of ordinary skill in the art to arrange the ferromagnetic element and reversed superconducting coil of Westphal with overlapping projected cross sections in view of the radially overlapping arrangement taught by CAO, as an arrangement of the magnetic field correction components about the magnet axis for adjusting magnetic field uniformity.
Claims 10-11, 13-15 are rejected under 35 U.S.C. 103 as being unpatentable over Westphal (U.S. Patent No. 5,545,997) in view of Dorri (U.S. Patent No. 5,594,401).
Regarding claim 10, Westphal does not expressly teach "wherein the ferromagnetic element comprises a ferrous material."
Dorri, however, teaches an MRI superconducting magnet having ferromagnetic rings 140 and 142, and expressly teaches that the ferromagnetic rings may comprise carbon steel, thereby teaching a ferrous material (Fig. 1; col. 5).
It would have been obvious to one of ordinary skill in the art to form the ferromagnetic element of Westphal from the carbon steel taught by Dorri, since Dorri teaches use of carbon steel for ferromagnetic elements in a superconducting MRI magnet, thereby providing a suitable ferromagnetic material for influencing the magnetic field.
Regarding claim 11, Westphal does not expressly teach "wherein the ferromagnetic element is attached to the reversed superconducting coil and the one of the plurality of superconducting coils."
Dorri, however, teaches a superconductive MRI magnet in which the superconductive main coils and ferromagnetic rings form part of a single superconductive coil assembly. Dorri further teaches an embodiment in which ferromagnetic rings 240 and 242 are attached to coil
housing 214, with the superconducting coils being supported and maintained as components of the superconductive coil assembly (Figs. 2-3; col. 5).
It would have been obvious to one of ordinary skill in the art to mechanically attach the
ferromagnetic element of Westphal with the adjacent superconducting coil structure, including
the reversed superconducting coil and the one of the plurality of superconducting coils, in view
of Dorri's teaching of mechanically securing the ferromagnetic elements as part of the superconductive coil assembly, to maintain the components in their intended relative positions within the magnet assembly.
Regarding claim 13, Westphal does not expressly teach "wherein the ferromagnetic element is configured to modify an inter-coil force within the main magnet such that an outwardly directed force that would otherwise act on the end coil of the main magnet in an absence of the ferromagnetic element is reduced by one of at least 30%, at least 40%, at least 50%, or at least 60%."
Dorri teaches incorporating ferromagnetic rings into a superconducting MRI magnet and selecting the configuration of the ferromagnetic rings to modify the magnetic field produced by the superconducting coils. The ferromagnetic rings are used to compensate magnetic field distortions and obtain a desired magnetic field distribution within the imaging region.
It would have been obvious to one of ordinary skill in the art to optimize the dimensions and placement of the ferromagnetic element of Westphal to obtain a desired magnetic interaction between the reversed superconducting coil and the end coil. The size and position of the ferromagnetic element are result effective variables because changing these parameters
changes the magnetic field distribution and, consequently, the electromagnetic interaction
between the coils. Selecting these parameters to reduce the outwardly directed force on the end coil by at least 30%, at least 40%, at least 50%, or at least 60% would have amounted to
routine optimization of the disclosed ferromagnetic element to obtain a desired degree of force reduction.
Regarding claim 14, Westphal and Dorri do not expressly teach "wherein the ferromagnetic element is configured to modify the inter-coil force within the main magnet such that an inwardly-directed force acts on the one of the plurality of superconducting coils."
Dorri, however, teaches using ferromagnetic rings in the superconducting magnet and selecting the configuration of the ferromagnetic rings to modify the magnetic field produced by the superconducting coils.
It would have been obvious to optimize the dimensions and placement of the ferromagnetic element of Westphal to obtain the desired magnetic interaction between the reversed superconducting coil and the superconducting coil and to continue such optimization until the outwardly directed force is reduced and inverted such that an inwardly directed force acts on the superconducting coil. Such a result represents further optimization of the same magnetic interaction and would predictably reduce expansive loading on the magnet support structure.
Regarding claim 15, Westphal does not expressly teach "wherein the ferromagnetic element is configured to modify an inter-coil force within the main magnet such that an inwardly directed force that would otherwise act on the end coil in an absence of the ferromagnetic element is increased by one of at least 10%, at least 20%, or at least 30%."
Dorri teaches using ferromagnetic rings in a superconducting MRI magnet and selecting the configuration of the ferromagnetic rings to modify the magnetic field produced by the
superconducting coils.
It would have been obvious to one of ordinary skill in the art to optimize the dimensions and placement of the ferromagnetic element of Westphal to obtain a desired magnetic interaction between the reversed superconducting coil and the end coil. The size and position of the ferromagnetic element are result effective variables because changing these parameters changes the magnetic field distribution and corresponding electromagnetic interaction between the coils. Selecting these parameters to increase the inwardly directed force acting on the end coil by at least 10%, at least 20%, or at least 30% would have amounted to routine optimization of the disclosed ferromagnetic element to obtain a desired degree of compressive force on the end coil.
Conclusion
9. The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Xu (US Publication 20020163412) discloses Superconducting Magnetic Resonance Imaging Magnet Assembly And Method With Reverse Wire Channel Orientation.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to TAQI R NASIR whose telephone number is (571)270-1425. The examiner can normally be reached 9AM-5PM EST M-F.
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/TAQI R NASIR/Examiner, Art Unit 2858 /JERMELE M HOLLINGTON/Primary Examiner, Art Unit 2858
