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 .
Status of Claims
Claims 1-18 are pending in the application, with Claims 1, 7, and 13 having each been amended.
Response to Remarks
Drawing Objections
Examiner acknowledges the submitted Replacement Sheet overcoming the objection to the drawings set forth in the previous Office Action.
Claim Rejections - 35 U.S.C. 102, 103
Independent claims 1, 7, and 13 have been amended to clarify “second parameters of a second Gaussian distribution associated with imaging characteristics of the imaging system” to “second parameters of a second Gaussian distribution representing a point spread function (PSF) of the imaging system”. In light of these amendments and Applicant’s arguments, the rejections under 35 USC 102 are withdrawn and new rejections under 35 USC 103 are set forth below.
Applicant argues that the “intrinsic resolution of the PET scanner” mentioned in Trotter et al. does not read on the claimed “PSF of the imaging system”, as the intrinsic resolution refers to resolution dictated by physical limitations of a PET scanner such as scintillation crystal size (Remarks, second page, second full paragraph).
Examiner respectfully disagrees. Trotter defines “GF-18 is a 3D Gaussian kernel representing the image blur due to the F-18's annihilation photon non-collinearity, detector response function and positron range.” Especially due to the inclusion of “detector response function”, when Trotter says “the kernel GF-18 can be taken as representative of the kernel due to the intrinsic resolution of the PET scanner”, it includes various factors contributing to the PSF of the imaging system. In fact, the resolution dictated by the scintillation crystal size is inextricably one such factor. The “3D Gaussian kernel” reads on “a second Gaussian distribution representing a point spread function (PSF)”.
Applicant argues that Trotter cannot be seen to disclose or to suggest determination of the first and second parameters of the Gaussian distributions (Remarks, second page, third full paragraph).
Examiner respectfully disagrees. As “3D Gaussian kernels” representing both a positron range distribution of the radioactive tracer and a PSF of the imaging system are disclosed in Trotter and used in calculations, it is inherently disclosed that a step of determining the parameters of each distribution occurred prior to being used in Equation (3).
Applicant argues that Equation (3) of Trotter, which includes the convolution of two kernels (matrices) to generate image p’, cannot be seen to disclose or to suggest generation of a system matrix based on first parameters of a first Gaussian distribution and second parameters of a second Gaussian distribution (Remarks, second page, fourth full paragraph).
Examiner respectfully disagrees, acknowledging that the generation of the system matrix is not explicitly taught in Trotter. The previously set forth 102 rejection is reformulated as a 103 rejection below to expand upon and clarify Examiner’s position.
Claim Interpretation
The following is a quotation of 35 U.S.C. 112(f):
(f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The following is a quotation of pre-AIA 35 U.S.C. 112, sixth paragraph:
An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked.
As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph:
(A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function;
(B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and
(C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function.
Use of the word “means” (or “step”) in a claim with functional language creates a rebuttable presumption that the claim limitation is to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites sufficient structure, material, or acts to entirely perform the recited function.
Absence of the word “means” (or “step”) in a claim creates a rebuttable presumption that the claim limitation is not to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is not interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites function without reciting sufficient structure, material or acts to entirely perform the recited function.
Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action.
This application includes one or more claim limitations that do not use the word “means,” but are nonetheless being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, because the claim limitation(s) uses a generic placeholder that is coupled with functional language without reciting sufficient structure to perform the recited function and the generic placeholder is not preceded by a structural modifier. Such claim limitation(s) is/are: “processing unit” in claim 7.
Because this/these claim limitation(s) is/are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, it/they is/are being interpreted to cover the corresponding structure described in the specification as performing the claimed function, and equivalents thereof.
If applicant does not intend to have this/these limitation(s) interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, applicant may: (1) amend the claim limitation(s) to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph (e.g., by reciting sufficient structure to perform the claimed function); or (2) present a sufficient showing that the claim limitation(s) recite(s) sufficient structure to perform the claimed function so as to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph.
Claim Rejections - 35 USC § 103
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, 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.
Claims 1-6 are rejected under 35 U.S.C. 103 as being unpatentable over Trotter (US 20040225214 A1).
Regarding claim 1, Trotter teaches a method comprising:
obtaining emission data associated with a radioactive tracer and acquired by an imaging system (paragraph [0009]);
determining first parameters of a first Gaussian distribution representing a positron range distribution of the radioactive tracer (paragraphs [0051-52]: RI-124 in Equation (3) is a 3D Gaussian kernel representing the additional degradation in resolution due to the positron range of I-124);
determining second parameters of a second Gaussian distribution representing a point spread function (PSF) of the imaging system (paragraphs [0051-52]: GF-18 in Equation (3) is a 3D Gaussian kernel representing the image blur due to the F-18’s annihilation photon non-collinearity, detector response function and positron range. Note the image blur introduced by the F-18 positron range is negligible compared with the intrinsic resolution of the PET scanner, so GF-18 can be taken as representative of the kernel due to the intrinsic resolution of the PET scanner)
reconstructing a three-dimensional image (paragraph [0051] and Equation (3): image ρ’) based on the emission data (paragraph [0051] and Equation (3): 3D distribution of PET radionuclide ρ) and the system matrix
Trotter does not explicitly teach generating a system matrix based on the first parameters and the second parameters.
Trotter teaches instead a 3D Gaussian kernel based on the first parameters (implicitly discretized into a matrix in Trotter, as it is used for image reconstruction) and a 3D Gaussian kernel based on the second parameters. Implementing Equation (3) in practice exactly as Trotter defines (in pseudocode as an example) would be written as
Rho_prime = S * R_I124 * G_F18 * Rho
where all variables are matrices and “*” is convolution. A person of ordinary skill in the art would be motivated to store a general matrix based on the parameters representing the positron range and the parameters representing the PSF of the imaging system, for efficiency of repeated calculations. As matrix convolution is associative (meaning the convolution of R_I124 and G_F18 can be performed first rather than right-to-left), a person of ordinary skill would know to equivalently write
SYS_MATRIX = R_I124 * G_F18
Rho_prime = S * SYS_MATRIX * Rho
thus generating a “system matrix based on the first parameters and the second parameters” in a method trivially different from that taught by Trotter.
Regarding claim 2, Trotter does not teach a method according to claim 1, further comprising:
determining the positron range distribution of the radioactive tracer; and
determining the first Gaussian distribution based on the positron range distribution.
Per applicant’s disclosure, determining the positron range distribution of the radioactive tracer is a well-known technique (paragraph [0040]: “the statistical distribution of [the positron annihilation] distances can be modeled as is known in the art”). Approximating a Gaussian via statistical fitting is a well-known mathematical technique.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to apply known techniques (determining the positron range distribution of a radioactive tracer, and obtaining via statistical fitting a Gaussian that approximates the distribution) to a known method ready for improvement (the teachings of Trotter) to yield predictable results (an image reconstruction technique incorporating the effects of positron range blurring, with the positron range distribution approximated as a Gaussian, with the benefits being improved resolution and a convolution calculation that is computationally lighter than using a non-Gaussian distribution). See KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007).
Regarding claim 3, it is well-known in the art that the positron range distribution of the radioactive tracer is not Gaussian, e.g. as in Kertész et al., “Implementation of a Spatially-Variant and Tissue-Dependent Positron Range Correction for PET/CT Imaging”, Frontiers in Physiology (Volume 13), pp. 1-17, doi: 10.3389/fphys.2022.818463. See Page 7, Figure 4 A-E.
Regarding claim 4, Trotter teaches generating the system matrix comprising convolving a first PSF model based on the first parameters with a second PSF model based on the second parameters (paragraph [0054]: “convolved with Gaussian PSFs according to Equation (3)”, implying the aforementioned Gaussian kernels are PSFs).
Regarding claim 5, Trotter teaches generating the system matrix comprising convolving a first PSF model based on the first parameters with a second PSF model based on the second parameters (paragraph [0054]: “convolved with Gaussian PSFs according to Equation (3)”, implying the aforementioned Gaussian kernels are indeed PSFs).
Regarding claim 6, it is well-known in the art that the positron range distribution of the radioactive tracer is not Gaussian, e.g. as in Kertész et al., “Implementation of a Spatially-Variant and Tissue-Dependent Positron Range Correction for PET/CT Imaging”, Frontiers in Physiology (Volume 13), pp. 1-17, doi: 10.3389/fphys.2022.818463. See Page 7, Figure 4 A-E.
Claims 7-12 are rejected under 35 U.S.C. 103 as being unpatentable over Trotter in view of Kaushik et al. (US 2022/0101576 A1).
Regarding claim 7, Trotter teaches a system comprising:
an imaging system to acquire emission data from an object while a radioactive tracer is present in the object (paragraph [0009]);
a processing unit (implicitly present for performing the calculations in a PET system) to:
determine first parameters of a first Gaussian distribution representing a positron range distribution of the radioactive tracer (paragraphs [0051-52]: RI-124 in Equation (3) is a 3D Gaussian kernel representing the additional degradation in resolution due to the positron range of I-124);
determine second parameters of a second Gaussian distribution representing a point spread function (PSF) of the imaging system (paragraphs [0051-52]: GF-18 in Equation (3) is a 3D Gaussian kernel representing the image blur due to the F-18’s annihilation photon non-collinearity, detector response function and positron range. Note the image blur introduced by the F-18 positron range is negligible compared with the intrinsic resolution of the PET scanner, so GF-18 can be taken as representative of the kernel due to the intrinsic resolution of the PET scanner)
reconstruct a three-dimensional image (paragraph [0051] and Equation (3): image ρ’) based on the emission data (paragraph [0051] and Equation (3): 3D distribution of PET radionuclide ρ) and the system matrix
Trotter does not explicitly teach generating a system matrix based on the first parameters and the second parameters; see the above explanation.
Trotter does not teach a display to display the three-dimensional image.
In the same field of endeavor, Kaushik teaches a display to display the three-dimensional image (paragraph [0029]). In light of the teachings of Kaushik, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Trotter such that a display is added to display the reconstructed three-dimensional image. The display improves functionality by providing the benefit of allowing the user to view the image to analyze it for abnormalities or diagnose conditions.
Regarding claim 8, Trotter does not teach a system according to claim 7, the processing unit to:
determine the positron range distribution of the radioactive tracer; and
determine the first Gaussian distribution based on the positron range distribution.
Per applicant’s disclosure, determining the positron range distribution of the radioactive tracer is a well-known technique (paragraph [0040]: “the statistical distribution of [the positron annihilation] distances can be modeled as is known in the art”). Approximating a Gaussian via statistical fitting is a well-known mathematical technique.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to apply known techniques (determining the positron range distribution of a radioactive tracer, and obtaining via statistical fitting a Gaussian that approximates the distribution) to a known device ready for improvement (the teachings of Trotter and Kaushik) to yield predictable results (an image reconstruction system incorporating the effects of positron range blurring, with the positron range distribution approximated as a Gaussian, with the benefits being improved resolution and a convolution calculation that is computationally lighter than using a non-Gaussian distribution). See KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007).
Regarding claim 9, it is well-known in the art that the positron range distribution of the radioactive tracer is not Gaussian, e.g. as in Kertész et al., “Implementation of a Spatially-Variant and Tissue-Dependent Positron Range Correction for PET/CT Imaging”, Frontiers in Physiology (Volume 13), pp. 1-17, doi: 10.3389/fphys.2022.818463. See Page 7, Figure 4 A-E.
Regarding claim 10, Trotter teaches generation of the system matrix comprising convolving a first PSF model based on the first parameters with a second PSF model based on the second parameters (paragraph [0054]: “convolved with Gaussian PSFs according to Equation (3)”, implying the aforementioned Gaussian kernels are PSFs).
Regarding claim 11, Trotter teaches generation of the system matrix comprising convolving a first PSF model based on the first parameters with a second PSF model based on the second parameters (paragraph [0054]: “convolved with Gaussian PSFs according to Equation (3)”, implying the aforementioned Gaussian kernels are PSFs).
Regarding claim 12, it is well-known in the art that the positron range distribution of the radioactive tracer is not Gaussian, e.g. as in Kertész et al., “Implementation of a Spatially-Variant and Tissue-Dependent Positron Range Correction for PET/CT Imaging”, Frontiers in Physiology (Volume 13), pp. 1-17, doi: 10.3389/fphys.2022.818463. See Page 7, Figure 4 A-E.
Claims 13-18 are rejected under 35 U.S.C. 103 as being unpatentable over Trotter in view of Kaushik.
Regarding claim 13, Trotter teaches a processing unit (implicitly present) to:
acquire emission data from an object while a radioactive tracer is present in the object (paragraph [0009]);
determine first parameters of a first Gaussian distribution representing a positron range distribution of the radioactive tracer (paragraphs [0051-52]: RI-124 in Equation (3) is a 3D Gaussian kernel representing the additional degradation in resolution due to the positron range of I-124);
determine second parameters of a second Gaussian distribution representing a point spread function (PSF) of the imaging system (paragraphs [0051-52]: GF-18 in Equation (3) is a 3D Gaussian kernel representing the image blur due to the F-18’s annihilation photon non-collinearity, detector response function and positron range. Note the image blur introduced by the F-18 positron range is negligible compared with the intrinsic resolution of the PET scanner, so GF-18 can be taken as representative of the kernel due to the intrinsic resolution of the PET scanner)
reconstruct a three-dimensional image (paragraph [0051] and Equation (3): image ρ’) based on the emission data (paragraph [0051] and Equation (3): 3D distribution of PET radionuclide ρ) and the system matrix
Trotter does not explicitly teach generating a system matrix based on the first parameters and the second parameters; see the above explanation.
Trotter does not teach a non-transitory computer-readable medium storing program code executable by a processing unit to perform the claimed functions and display the three-dimensional image.
In the same field of endeavor, Kaushik teaches a non-transitory computer-readable medium storing program code executable by a processing unit (paragraph [0028]) to display the image (paragraph [0029]). In light of the teachings of Kaushik, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Trotter such that a non-transitory computer-readable medium storing program code executable by a processing unit is used to perform the functions and display the reconstructed three-dimensional image. The non-transitory computer-readable medium is a functional necessity for performing the computations, and the display improves functionality by providing the benefit of allowing the user to view the image to analyze it for abnormalities or diagnose conditions.
Regarding claim 14, Trotter does not teach a medium according to claim 13, the program code executable by a processing unit to:
determine the positron range distribution of the radioactive tracer; and
determine the first Gaussian distribution based on the positron range distribution.
Per applicant’s disclosure, determining the positron range distribution of the radioactive tracer is a well-known technique (paragraph [0040]: “the statistical distribution of [the positron annihilation] distances can be modeled as is known in the art”). Approximating a Gaussian via statistical fitting is a well-known mathematical technique.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to apply known techniques (determining the positron range distribution of a radioactive tracer, and obtaining via statistical fitting a Gaussian that approximates the distribution) to a known device ready for improvement (the teachings of Trotter and Kaushik) to yield predictable results (a non-transitory computer-readable medium for use in an image reconstruction system incorporating the effects of positron range blurring, with the positron range distribution approximated as a Gaussian, with the benefits being improved resolution and a convolution calculation that is computationally lighter than using a non-Gaussian distribution). See KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007).
Regarding claim 15, it is well-known in the art that the positron range distribution of the radioactive tracer is not Gaussian, e.g. as in Kertész et al., “Implementation of a Spatially-Variant and Tissue-Dependent Positron Range Correction for PET/CT Imaging”, Frontiers in Physiology (Volume 13), pp. 1-17, doi: 10.3389/fphys.2022.818463. See Page 7, Figure 4 A-E.
Regarding claim 16, Trotter teaches generation of the system matrix comprising convolving a first PSF model based on the first parameters with a second PSF model based on the second parameters (paragraph [0054]: “convolved with Gaussian PSFs according to Equation (3)”, implying the aforementioned Gaussian kernels are PSFs).
Regarding claim 17, Trotter teaches generation of the system matrix comprising convolving a first PSF model based on the first parameters with a second PSF model based on the second parameters (paragraph [0054]: “convolved with Gaussian PSFs according to Equation (3)”, implying the aforementioned Gaussian kernels are PSFs).
Regarding claim 18, it is well-known in the art that the positron range distribution of the radioactive tracer is not Gaussian, e.g. as in Kertész et al., “Implementation of a Spatially-Variant and Tissue-Dependent Positron Range Correction for PET/CT Imaging”, Frontiers in Physiology (Volume 13), pp. 1-17, doi: 10.3389/fphys.2022.818463. See Page 7, Figure 4 A-E.
Conclusion
Applicant’s amendment necessitated the new grounds of rejection presented in this office action. Accordingly, THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to WILLIAM L TAYLOR whose telephone number is (571)272-8389. The examiner can normally be reached Mon-Fri, 8am-4pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, David Makiya can be reached at (571) 272-2273. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/WILLIAM LAURENCE TAYLOR/Examiner, Art Unit 2884
/DAVID J MAKIYA/Supervisory Patent Examiner, Art Unit 2884
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