DETAILED ACTION
Election/Restrictions
Claims 13-33 remain withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 3/3/2026.
Response to Arguments
Applicant's arguments filed 7/21/2026 have been fully considered but they are not persuasive except as noted below.
Applicant states that claim 1 has been amended to overcome the rejection. The rejection regarding “the sub-region” is withdrawn in light of the claim amendments. The rejection regarding “the programmable instructions” in maintained. The amendment did not address this limitation, and claim 1 still recites “program instructions” followed by “the programmable instructions”.
Applicant argues that each and every recitation of claim is not disclosed by Bulsink in view of Fukutani. Examiner disagrees and submits that this is a general allegation and does not specifically point out how the language of the claims that patentably distinguishes over the references. Each limitation of all the claims is mapped to Bulsink in view of Fukutani, below.
Applicant argues that the invention addresses problems in OA imaging related to chromophores. Examiner notes that the claims are examined as written, and limitations from the specification are not read into the claims. The problem Applicant set out to solve does not distinguish claimed structure and operations that Bulsink in view of Fukutani teach.
Applicant argues that Bulsink uses US segmentation to identify tissue type, such as water, soft tissue or muscle, and is therefore directed to fluence variation caused by tissue rather than to Hb chromophores. Examiner notes this argument supports the rejection. Claim 1 requires identifying an extend of non-Hb chromophore, and water, soft tissue and muscle are non-Hb chromophores in the sub-region. Bulsink identifies them by US segmentation (Fluence Compensation, pg. 4, Imaging a Two Slab Phantom, pg. 7) and assigns each its optical absorption coefficient ua (Light Propagation Model, pg. 5, Table 1). Applicant’s own claims identify the extent by classifying the sub-region into tissue types (Claim 4) and list water as a non-Hb chromophore (Claim 12).
Applicant argues that Bulsink is not directed to identifying and analyzing Hb chromophores, the light-absorbing pigment in blood. Applicant further argues that correcting for tissue effects on sO2 is not equivalent to identifying and analyzing pigments within blood. Examiner disagrees and submits that Applicant’s arguments are not commensurate in scope with the claimed invention. Claim 1 does not require identifying Hb chromophores, it requires computing an amount of the Hb chromophore based on the acoustic pressure data and the value assigned to the non-Hb chromophore factor. Bulsink does exactly this, it computes the HbO2 and HbR amounts by linear unmixing of the PA pressure data after normalizing by the fluence derived from the assigned non-Hb ua values (equations 1-7, p. 4).
Applicant argues that nothing in Bulsink suggests that blood-based analysis must occur, and that Bulsink details only tissue-based analysis. Examiner disagrees and submits that Bulsink’s stated purpose is quantitative sO2 imaging, which is an analysis of hemoglobin in blood (Introduction, p. 2; Oxygen Saturation Imaging Using Linear Unmixing, pg. 4). Bulsink’s tissue-based fluence correction is performed to enable that blood-based analysis.
The prior art rejections are maintained.
Claim Rejections - 35 USC § 112
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.
Claims 1-12 are 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 1 recites “program instructions” and then recites “the programmable instructions”. There is insufficient antecedent basis for the limitation “the programmable instructions”. For purposes of examination the indefinite limitation has been deemed to claim “the program instructions”.
Claim Rejections - 35 USC § 103
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 (i.e., changing from AIA to pre-AIA ) 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.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claim(s) 1-12 is/are rejected under 35 U.S.C. 103 as being unpatentable over “Oxygen Saturation Imaging Using LED-Based Photoacoustic System” to Bulsink et al. (hereinafter, Bulsink) in view of US 20120296192 A1 to Fukutani.
Regarding Claim 1, Bulsink discloses an optoacoustic (OA) imaging system (Introduction, page 2 “PAI or optoacoustic imaging is a modality that combines the advantages of ultrasound (US) and optical imaging techniques.”), comprising inter alia:
one or more light sources configured to generate a first light pulse having a first predominant wavelength (Materials and Methods “For oxygen saturation imaging, we used a dual-wavelength approach with an LED array having 750nm and 850 nm elements.”);
an OA probe operatively coupled to the one or more light sources (Light Propagation Model, page 5 “The LED units were placed on either side of the transducer…”), the OA probe configured to deliver the first light pulse to a region of interest (ROI) of tissue, the ROI including i) at least one non-hemoglobin (non-Hb) chromophore, and ii) at least one hemoglobin (Hb) chromophore (The probe of Bulsink is capable of delivering light to tissue ROIS containing both hemoglobin and non-hemoglobin chromophores – the entire paper discloses correcting for non-hemoglobin chromophore contributions to the OA signal) (Introduction, page 2 “Hemoglobin is an excellent optical absorber with well-defined absorption spectra in the near-infrared wavelengths. Hence, measurement of sO2 is undoubtedly the most interesting application of PAI.”) (Introduction, pages 2-3 “In this work, we utilized the information offered by conventional US imaging to segment the tissue and used Monte-Carlo simulations of the LED probe to estimate the fluence map in the imaging plane.”),
the OA probe including a transducer array that is configured to collect OA return signal data associated with a response of the ROI to one or more of the first laser light pulses (Materials and Methods, page 3 “A 128 element, 7 MHz linear US transducer with a bandwidth of 80% was used in the probe (Figure 1e).”) (Introduction, page 2 “In PAI, nanosecond pulsed light excitation of optical absorbers in the tissue results in US signal generation. These US signals can be detected using US transducers.”);
memory configured to store program instructions and one or more processors configured to execute the programmable instructions to (Ultrasound Segmentation “All image processing operations were performed using MATLAB (MathWorks, MA, USA) imaging processing toolbox.”):
generate an acoustic pressure data set based on the OA return signal data, the acoustic pressure data associated with a sub-region of the ROI, wherein the acoustic pressure data is dependent on a composition of hemoglobin (Hb) and non-Hb chromophores in the sub-region (The reconstructed PA pressure image (e.g., result of Equation 1) is the acoustic pressure data set. The pressure data at any subregion depends on both the Hb chromophores (through the extinction coefficients described under Oxygen Saturation Imaging Using Linear Unmixing at page 4) and the non-Hb chromophores (through the fluence of Φ which is shaped by the background absorption µa of the non-Hb tissue) (Oxygen Saturation Imaging Using Linear Unmixing, page 4 “PA initial pressure resulting from pulsed light excitation of optical absorber with the assumption of stress confinement can be expressed as [Equation 1] … Thus the reconstructed PA image can be written as [Equation 2]”) (Introduction “Fluence variations in the tissue hinder the possibility of quantitative sO2 imaging.”);
identify an extent of the at least one non-Hb chromophore within the sub-region (The US segmentation identifies which tissue type, whether it’s water, soft tissue or muscle, occupies each subregion. Each tissue type is defined by its non-Hb chromophore content. The binary mask is the spatial record of that identification) (Fluence Compensation, page 4, “The US image was segmented to obtain a binary mask of the tissue boundary.”) (Imaging a Two Slab Phantom, page 7 “B-mode US imaging was performed and used to identify the two mediums.”);
assign a value to a non-Hb chromophore factor based on the extent of the at least one non-Hb chromophore within the sub-region (The ua values in Table 1 are assigned per tissue type based on which type the segmentation identified in each sub region. Water subject gets water optical properties, soft tissue gets soft tissue optical properties and the assignment is conditional on the segmentation result.) (Light Propagation Model, page 5 “A binary mask from the US segmentation and prior optical properties of the tissue was used as input to the model.”); and
compute an amount of at least one of i) the Hb chromophore or ii) a second non-Hb chromophore in the sub-region based on the acoustic pressure data and the value assigned to the non-Hb chromophore factor (Equation 2 at Oxygen Saturation Imaging Using Linear Unmixing at page 2 shows that to get the Hb amount, PA pressure signal p (the acoustic pressure data) is divided by the fluence Φ (which is calculated using the assigned ua non-Hb factor values from Table 1. Both inputs are required, Hb cannot be computed without the pressure measurement and the non-Hb factor, thereby, satisfying this “computer an amount” limitation.
Bulsink discloses the claimed invention except for expressly disclosing where the first light pulse is a first laser light pulse having a first predominant wavelength. However, Fukutani teaches a photoacoustic imaging apparatus (Abstract) for using in skin imaging ([0043]) and expressly states in [0039] that the light source for such imaging may be a laser. One having an ordinary skill in the art at the time the invention was filed would have found it obvious to modify the LED light source of Bulsink to be the laser of Fukutani, as Fukutani teaches at [0039] that a laser is a preferable light source over a light emitting diode, and the two are interchangeable. A skilled artisan would have found such substitution of a LED light source for a laser light source, as this would have been routine in the art as both are excited as but sufficient light sources for biological imaging.
Regarding Claim 2, Bulsink teaches the system of claim 1, wherein the one or more processors are further configured to identify the extent of at least one non-Hb chromophore within the sub-region, by analyzing an imaging data set for the sub-region to determine an aspect of the composition related to the extent of the one non-Hb chromophore (Ultrasound Segmentation, page 5 “The tissue boundary was obtained by segmenting the US image. First, a median filter was applied to smoothen the speckles in the US image. Next, a binary image was obtained by thresholding the grayscale US image.”).
Regarding Claim 3, Bulsink teaches the system of claim 1, wherein the ROI includes first and second sub-regions having different first and second compositions, the one or more processors further configured to i) identify first and second extents of the non-Hb chromophore within the first and second sub-regions, respectively, and, based thereon, to assign first and second values to the non-Hb chromophore factor for the first and second sub-regions, respectively (Water and soft tissue are two subregions with explicit different compositions – Table 1 shows different ua values assigned to each.) (Imaging a Two Slab Phantom, page 7 “Water was used for the top slab and a soft tissue-mimicking medium for the bottom slab Figure 1d… B-mode US imaging was performed and used to identify the two mediums.”).
Regarding Claim 4, Bulsink teaches the system of claim 1, wherein, to identify the extent, the one or more processors are further configured to ii) classify the sub-region into one or more tissue types (Discussion, page 12 “we segmented the phantom and tissue as two layers (water and soft tissue layer in phantom, water and muscle in mouse imaging, and water and soft tissue in human wrist imaging)”.
Regarding Claim 5, Bulsink teaches the system of claim 1, wherein the acoustic pressure data for the ROI represents an OA image and wherein the one or more processors are further configured to: apply a fluence adjustment to the acoustic pressure data of the OA image to form a fluence- adjusted OA image; and compute a parametric map based on the fluence-adjusted OA image after applying the fluence adjustment (Fluence Compensation, pages 4-5 “The binary mask and the optical properties of the tissue were used in the light propagation model to obtain fluence maps… PA images at two wavelengths were normalized using the fluence maps… Linear unmixing was used to obtain oxygen saturation images from the fluence normalized PA images.”) (The fluence normalization is the fluence adjustment and the resulting sO2 image is the parametric map, see Equation 3 at page 4).
Regarding Claim 6, Bulsink teaches the system of claim 1, wherein the one or more processors are further configured to assign the value for the non-Hb chromophore factor based on i) an optical absorption coefficient of the non-Hb chromophore in the sub-region (Light Propagation Model, page 5 “A binary mask from the US segmentation and prior optical properties of the tissue was used as input to the model.”) (see Table 1 headers optical absorption coefficient ua and reduced scattering coefficient u’s).
Regarding Claim 7, Bulsink teaches the system of claim 1, wherein the non-Hb chromophore factor corresponds to i) an optical absorption coefficient of the non-Hb chromophore in the sub-region (Light Propagation Model, page 5 “A binary mask from the US segmentation and prior optical properties of the tissue was used as input to the model.”) (see Table 1 headers optical absorption coefficient ua and reduced scattering coefficient u’s).
Regarding Claim 8,teaches discloses the system of claim 1, wherein the non-Hb chromophore factor corresponds to a non-blood absorption coefficient and wherein, to compute the amount of the Hb chromophore, the one or more processors are further configured to: determine a tissue absorption coefficient based on the acoustic pressure data (the ua value devired from the PA pressure data and the fluence model); determine a blood absorption coefficient based on the tissue absorption coefficient and the value of the non-blood absorption coefficient (the assigned ua from Table 1 for the background tissue); and determine the amount of the Hb chromophore based on the blood absorption coefficient (the b value, the fluence corrected PA signal isolating Hb contribution) and an Hb extinction coefficient (the HbR and eHbO in matrix A) (see all Equations 1-7 at page 4).
Regarding Claim 9, teaches discloses wherein the one or more processors are further configured to compute a parametric map based on the amount of the Hb chromophore (see Equation 7 at page 4 where the sO2 image is a parametric map computer from the computed Hb chromophore amounts cHbO2 and cHbR.
Regarding Claim 10, Bulsink teaches the system of claim 1, wherein the acoustic pressure data includes a collection of pressure data values representative of an acoustic response at corresponding positions throughout the sub-region of the ROI (The 128 element array collects a separate pressure signal at each transducer position, and produces a collection of pressure data values at corresponding positions across the subregion) (Materials and Methods, page 3 “A 128 element, 7 MHz linear US transducer with a bandwidth of 80% was used in the probe (Figure 1e).”).
Regarding Claim 11, teaches discloses the system of claim 1, wherein the amount of the Hb chromophore includes a first amount for an oxygenated Hb (HbO) chromophore and a second amount for a de-oxygenated Hb (HbR) chromophore (The linear unmixing at set forth in Equation 5 at page 4 solves for separate amounts of both HbO2 and HbR).
Regarding Claim 12, Bulsink teaches the system of claim 1, wherein the non-Hb chromophore includes a water chromophore (Discussion, page 12 “… we segmented the phantom and tissue as two layers (water and soft tissue layer in phantom, water and muscle in mouse imaging, and water and soft tissue in human wrist imaging)…”).
Conclusion
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 SEAN PATRICK DOUGHERTY whose telephone number is (571)270-5044. The examiner can normally be reached 8am-5pm (Pacific Time).
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/SEAN P DOUGHERTY/Primary Examiner, Art Unit 3791
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