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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on September 2nd, 2026 has been entered.
Amendment Entered
In response to the amendment filed on September 2nd, 2026, amended claims 1, 3, 6, 8, and 18 are entered. Claims 1-10 and 18-19 are currently under examination.
Response to Arguments
Applicant's remarks and amendments with respect to the abstract objection have been fully considered. The objection is withdrawn in view of the amendment.
Applicant's remarks and amendments with respect to the claim objections have been fully considered. The objections are withdrawn in view of the amendment.
Applicant's remarks and amendments with respect to the rejections under 35 U.S.C. 112(b) have been fully considered. The rejections are withdrawn in view of the amendment.
Applicant's arguments, filed on September 2nd, 2026, with respect to the rejections under 35 U.S.C. 101 have been fully considered but they are not persuasive. The rejections are maintained, and further clarified, in view of the amendment.
At Pg. 7 of the Reply, Applicant argues that “each independent claim now recites various processes performed by a bioimpedance device and electrode so that the claims are not directed to a mental process”. Examiner respectfully disagrees. Although the Applicant has amended the independent claims, the newly added limitations regarding the “bioimpedance device” and “electrode” recite data-gathering steps, which is considered insignificant extra-solution activity, which is separate from the abstract idea.
The steps of “determining, during the treatment, an impedance curve at the first frequency; determining, during the treatment, an impedance curve at the second, higher frequency; and determining a dry weight of the patient during the treatment based on a flattening of the impedance curves at the first frequency and the second, higher frequency during the treatment” recite an abstract idea in the form of a mental processes, as consistent with Mayo Collaborative Servs. v. Prometheus Labs., Inc., 566 U.S. 66 (2012). If a claim, under its broadest reasonable interpretation, covers performance in the mind but for the recitation of generic computer components, then it is still in the mental processes category unless the claim cannot practically be performed in the mind, see Intellectual Ventures I LLC v. Symantec Corp., 838 F.3d 1307, 1318 (Fed. Cir. 2016). Determining impedance changes over time and determining a dry weight based on the rate of change are assessments that may be performed by a human.
Therefore, the claims recite mental processes performed on a computer control system. The “Federal Circuit has explained, ‘[c]ourts have examined claims that required the use of a computer and still found that the underlying, patent-ineligible invention could be performed via pen and paper or in a person’s mind.’ Versata Dev. Group v. SAP Am., Inc., 793 F.3d 1306, 1335, 115 USPQ2d 1681, 1702 (Fed. Cir. 2015).” MPEP 2106.04(a)(2) III. There is no time limit recited for performing the steps. The claimed steps can be performed via pen and paper or in a person’s mind with no time restraint. The computer is merely utilized as a tool to perform the mental steps.
Applicant further argues wherein “any abstract idea is integrated into a practical application as the claims recite an improvement in a technical field of determining dry weight and disclose using the flattening of impedance curves or resistivities at two frequencies in normal range that is a technical improvement in the measuring dry weight technical field”. Examiner respectfully disagrees.
“The full scope of the claim under the BRI should be considered to determine if the claim reflects an improvement in technology (e.g., the improvement described in the specification).” MPEP 2106.05(a). “That is, the claim must include the components or steps of the invention that provide the improvement described in the specification.” Id.
“[I]n McRO, the court relied on the specification’s explanation of how the particular rules recited in the claim enabled the automation of specific animation tasks that previously could only be performed subjectively by humans, when determining that the claims were directed to improvements in computer animation instead of an abstract idea.” MPEP 2106.05 (a). There is no improvement to a computer or other technology. Unlike McRO, the claimed method invokes a computer as a tool to perform a mathematical concept and/or mental process. Therefore, it is unclear how the abstract idea can improve the standard functions of the additional elements.
The Examiner would like to clarify that the claimed steps do not improve the functioning of the data acquisition or the signal exchange. “It is important to note, the judicial exception alone cannot provide the improvement.” MPEP 2106.05(a). The data acquisition and signal exchange appear to perform the same with or without the abstract idea. Therefore, any improvement resides solely within the abstract idea. Therefore, the current claims are rejected under 35 U.S.C. 101.
Applicant's arguments, filed on February 26th, 2026, with respect to the rejections under 35 U.S.C. 103 have been fully considered, but they are not persuasive. The rejections are maintained, and further clarified, in view of the amendment.
At Pgs. 8-9 of the Reply, Applicant argues that “there is no motivation to combine Chamney and Zhu and a prima facie case of obviousness has not been established since the motivation to modify Chamney and Zhu is lacking” regarding both independent claims 1 and 6. Examiner respectfully disagrees. The prior art’s disclosure of more than one alternative does not constitute a teaching away from any of these alternatives. MPEP 2145 X. D. 1. Although Chamney and Zhu disclose different methods, both share the intended objective of determining dry weight. Furthermore, “[i]t is not necessary that the prior art suggest the combination to achieve the same advantage or result discovered by applicant.” MPEP 2144 IV. It is well-settled that the suggestion to combine need not come from the reference itself. “The rationale to modify or combine the prior art does not have to be expressly stated in the prior art; the rationale may be expressly or impliedly contained in the prior art or it may be reasoned from knowledge generally available to one of ordinary skill in the art, established scientific principles, or legal precedent established by prior case law.” MPEP 2144 I.
Chamney teaches wherein measurement of the impedance over at least two frequencies, better over a range of frequencies, allows an impedance locus to be constructed from which the resistance of the ICV and ECV components may be determined. Hence the volumes of the respective compartments can then be calculated from the resistance information, based on compartment resistivity constants available from prior studies for which the volumes were also determined by dilution measurements (Chamney [0050]). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have incorporated the flattening curve teachings of Zhu into the invention of Chamney, as Chamney already teaches the measurement of the impedance over at least two frequencies, because the slope of the curve approaching zero indicates that a substantially constant resistivity has been achieved, thereby reflecting that dry weight has been substantially attained. As the resistivity curve slope approaches zero, the hydration status of the patient approaches dry weight (Zhu [0048]).
Claim Objections
Claims 11-17 are objected to because they are identified as “Withdrawn”. However, if claims are “Withdrawn”, the claim limitations should still be present. In this case, Claims 11-17 are indicated as “Withdrawn” without any claim limitations present. Claim limitations can only be omitted when claims are “Canceled”. Appropriate correction is required.
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 1-10 and 18-19 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 “an electrode connected to the bioimpedance measurement device” in line 9. It is unclear as to whether this limitation is referring to the previously introduced “an electrode connected to the bioimpedance measurement device” from line 4 of Claim 1, or a separate element.
Claim 4 recites “an electrode array” in lines 1-2. It is unclear as to whether this limitation is referring to the previously introduced “electrode” limitations from Claim 1, or a separate element.
Claim 6 recites “a bioimpedance measurement device” in line 7. It is unclear as to whether this limitation is referring to the previously introduced “a bioimpedance measurement device” from line 3 of Claim 6, or a separate element.
Claim 6 recites “an electrode connected to the bioimpedance measurement device” in line 8. It is unclear as to whether this limitation is referring to the previously introduced “an electrode connected to the bioimpedance measurement device” from line 4 of Claim 6, or a separate element.
Claim 9 recites “an electrode array” in lines 1-2. It is unclear as to whether this limitation is referring to the previously introduced “electrode” limitations from Claim 6, or a separate element.
Claim Rejections - 35 USC § 101
35 U.S.C. 101 reads as follows:
Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title.
Claims 1-10 and 18-19 are rejected under 35 U.S.C. 101 because the claimed invention is directed to a judicial exception (i.e., a law of nature, a natural phenomenon, or an abstract idea) without significantly more. Each of Claims 1-10 and 18-19 has been analyzed to determine whether it is directed to any judicial exceptions.
Step 1
Claims 1-10 and 18-19 recite a series of steps or acts for assessing hydration for a patient. Thus, the claims are directed to a process, which is one of the statutory categories of invention.
Step 2A, Prong 1
Each of Claims 1-10 and 18-19 recites at least one step or instruction for assessing hydration for a patient, which is grouped as a mental process under the 2019 PEG. The claimed steps of determining can be practically performed in the human mind using mental steps or basic critical thinking, which are types of activities that have been found by the courts to represent abstract ideas.
Accordingly, each of Claims 1-10 and 18-19 recites an abstract idea.
Specifically, Claim 1 recites the abstract idea of: “determining, during the treatment, an impedance curve at the first frequency; determining, during the treatment, an impedance curve at the second, higher frequency; and determining a dry weight of the patient during the treatment based on a flattening of the impedance curves at the first frequency and the second, higher frequency during the treatment”.
Specifically, Claim 6 recites the abstract idea of: “determining euvolemia of the patient during the treatment based on when the resistivity at the first frequency and the second, higher frequency are both in the normal range”.
The other limitations regarding generating and measuring recite steps for pre-solution/data-gathering, which is considered insignificant, extra-solution activity. Furthermore, dependent claims 2-5, 7-10, and 18-19 merely include limitations that either further define the abstract idea (and thus don’t make the abstract idea any less abstract) or amount to no more than generally linking the use of the abstract idea to a particular technological environment or field of use because they’re merely incidental or token additions to the claims that do not alter or affect how the process steps are performed. The steps of generating and measuring recite data-gathering steps, which do not add a meaningful limitation to the method as they are insignificant extra-solution activity.
Accordingly, as indicated above, each of the above-identified claims recites an abstract idea.
Step 2A, Prong 2
The above-identified abstract idea in each of independent Claims 1 and 6 (and their respective dependent Claims 2-5, 7-10, and 18-19) is not integrated into a practical application under 2019 PEG because the additional elements (none present in independent Claims 1 and 6), either alone or in combination, generally link the use of the above-identified abstract idea to a particular technological environment or field of use. More specifically, the additional elements of: “bioimpedance measurement device”, “an electrode” in independent claims 1 and 6; and “an electrode array” in dependent claims 4 and 9 are generically recited sensors used for data-gathering. Nor do these above-identified additional elements serve to apply the above-identified abstract idea with, or by use of, a particular machine, effect a transformation or apply or use the above-identified abstract idea in some other meaningful way beyond generally linking the use thereof to a particular technological environment, such that the claim as a whole is more than a drafting effort designed to monopolize the exception. Furthermore, the above-identified additional elements do not add a meaningful limitation to the abstract idea because they amount to simply implementing the abstract idea on a computer. For at least these reasons, the abstract idea identified above in independent Claims 1 and 6 (and their respective dependent claims) is not integrated into a practical application under 2019 PEG.
Moreover, the above-identified abstract idea is not integrated into a practical application under 2019 PEG because the claimed method merely implements the above-identified abstract idea (e.g., mental process) using rules (e.g., computer instructions) executed by a computer (e.g., no computer is claimed). In other words, these claims are merely directed to an abstract idea with additional generic computer elements which do not add a meaningful limitation to the abstract idea because they amount to simply implementing the abstract idea on a computer.
Additionally, Applicant’s specification does not include any discussion of how the claimed invention provides a technical improvement realized by these claims over the prior art or any explanation of a technical problem having an unconventional technical solution that is expressed in these claims. That is, like Affinity Labs of Tex. v. DirecTV, LLC, the specification fails to provide sufficient details regarding the manner in which the claimed invention accomplishes any technical improvement or solution. Thus, for these additional reasons, the abstract idea identified above in independent Claims 1 and 6 (and their respective dependent claims) is not integrated into a practical application under the 2019 PEG. Accordingly, independent Claims 1 and 6 (and their respective dependent claims) are each directed to an abstract idea under 2019 PEG.
Step 2B
None of Claims 1-10 and 18-19 include additional elements that are sufficient to amount to significantly more than the abstract idea for at least the following reasons.
These claims require the additional elements of: “bioimpedance measurement device”, “an electrode” in independent claims 1 and 6; and “an electrode array” in dependent claims 4 and 9. Furthermore, no processor/computer is claimed, although present within the specification. The above-identified additional elements are generically claimed data-gathering sensors and even if a processor or computer were claimed, the computer components would just enable the above-identified abstract idea(s) to be conducted by performing the basic functions of automating mental tasks. The courts have recognized such computer functions as well understood, routine, and conventional functions when claimed in a merely generic manner (e.g., at a high level of generality) or as insignificant extra-solution activity. See, Versata Dev. Group, Inc. v. SAP Am., Inc. , 793 F.3d 1306, 1334, 115 USPQ2d 1681, 1701 (Fed. Cir. 2015); and OIP Techs., 788 F.3d at 1363, 115 USPQ2d at 1092-93.
Those in the relevant field of art would recognize the above-identified additional elements as being well-understood, routine, and conventional means for data-gathering and computing, as demonstrated by
Applicant’s specification (e.g. paragraphs [0051]-[0058]) which discloses that the processor(s) comprise generic computer components that are configured to perform the generic computer functions (e.g. determining) that are well-understood, routine, and conventional activities previously known to the pertinent industry.
Applicant’s Background in the specification; and
The non-patent literature of record in the application.
Furthermore, Applicant’s specification does not describe any special programming or algorithms required for the processor. This lack of disclosure is acceptable under 35 U.S.C. §112(a) since this hardware performs non-specialized functions known by those of ordinary skill in the computer arts. By omitting any specialized programming or algorithms, Applicant's specification essentially admits that this hardware is conventional and performs well understood, routine and conventional activities in the computer industry or arts. In other words, Applicant’s specification demonstrates the well-understood, routine, conventional nature of the above-identified additional elements because it describes these additional elements in a manner that indicates that the additional elements are sufficiently well-known that the specification does not need to describe the particulars of such additional elements to satisfy 35 U.S.C. § 112(a) (see Berkheimer memo from April 19, 2018, (III)(A)(1) on page 3). Adding hardware that performs “‘well understood, routine, conventional activit[ies]’ previously known to the industry” will not make claims patent-eligible (TLI Communications). Simply using a computer or other machinery in its ordinary capacity for economic or other tasks (e.g., to receive, store, or transmit data) or simply adding a general purpose computer or computer components after the fact to an abstract idea (e.g., a fundamental economic practice or mathematical equation) does not provide significantly more. See Affinity Labs v. DirecTV, 838 F.3d 1253, 1262, 120 USPQ2d 1201, 1207 (Fed. Cir. 2016) (cellular telephone); and TLI Communications LLC v. AV Auto, LLC, 823 F.3d 607, 613, 118 USPQ2d 1744, 1748 (Fed. Cir. 2016) (computer server and telephone unit). Moreover, implementing an abstract idea on a generic computer, does not add significantly more, similar to how the recitation of the computer in the claim in Alice amounted to mere instructions to apply the abstract idea of intermediated settlement on a generic computer.
A claim that purports to improve computer capabilities or to improve an existing technology may provide significantly more. McRO, Inc. v. Bandai Namco Games Am. Inc., 837 F.3d 1299, 1314-15, 120 USPQ2d 1091, 1101-02 (Fed. Cir. 2016); and Enfish, LLC v. Microsoft Corp., 822 F.3d 1327, 1335-36, 118 USPQ2d 1684, 1688-89 (Fed. Cir. 2016). However, a technical explanation as to how to implement the invention should be present in the specification for any assertion that the invention improves upon conventional functioning of a computer, or upon conventional technology or technological processes. That is, the disclosure must provide sufficient details such that one of ordinary skill in the art would recognize the claimed invention as providing an improvement. Here, Applicant’s specification does not include any discussion of how the claimed invention provides a technical improvement realized by these claims over the prior art or any explanation of a technical problem having an unconventional technical solution that is expressed in these claims. Instead, as in Affinity Labs of Tex. v. DirecTV, LLC 838 F.3d 1253, 1263-64, 120 USPQ2d 1201, 1207-08 (Fed. Cir. 2016), the specification fails to provide sufficient details regarding the manner in which the claimed invention accomplishes any technical improvement or solution.
For at least the above reasons, the methods of Claims 1-10 and 18-19 are directed to applying an abstract idea as identified above on a general purpose computer without (i) improving the performance of the computer itself, or (ii) providing a technical solution to a problem in a technical field. None of Claims 1-10 and 18-19 provides meaningful limitations to transform the abstract idea into a patent eligible application of the abstract idea such that these claims amount to significantly more than the abstract idea itself.
Taking the additional elements individually and in combination, the additional elements do not provide significantly more. Specifically, when viewed individually, the above-identified additional elements of “bioimpedance measurement device”, “an electrode”, and “an electrode array” do not add significantly more because they are simply an attempt to limit the abstract idea to a particular technological environment. That is, the additional elements fail to add meaningful limitations to the abstract idea because they represent insignificant extra-solution activity. When viewed as a combination, these above-identified additional elements simply implement the claimed functions with well-understood, routine and conventional activity specified at a high level of generality in a particular technological environment. As such, there is no inventive concept sufficient to transform the claimed subject matter into a patent-eligible application. When viewed as whole, the above-identified additional elements do not provide meaningful limitations to transform the abstract idea into a patent eligible application of the abstract idea such that the claims amount to significantly more than the abstract idea itself. Thus, Claims 1-10 and 18-19 merely apply an abstract idea to a computer and do not (i) improve the performance of the computer itself (as in Bascom and Enfish), or (ii) provide a technical solution to a problem in a technical field (as in DDR).
Therefore, none of the Claims 1-10 and 18-19 amounts to significantly more than the abstract idea itself. Accordingly, Claims 1-10 and 18-19 are not patent eligible and rejected under 35 U.S.C. 101.
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.
Claims 1-10 and 18-19 are rejected under 35 U.S.C. 103 as being unpatentable over Chamney (U.S. Publication No. 2004/0064063 A1; previously cited) in view of Zhu et al (U.S. Publication No. 2006/0122540 A1; previously cited).
Regarding Claim 1, Chamney discloses a method for assessing hydration for a patient using multiple frequency bioimpedance measurements (Method and a device for determining the dry weight of a patient with kidney failure; Abstract), the method comprising:
generating, by a bioimpedance measurement device, a first frequency (The means 5 is a bioimpedance measurement device…each of the electrode units 5 a and 5 b consists of a current injection electrode and a potential pick up electrode…currents of different alternating frequencies are applied to the patient via the electrodes; [0049-0050]);
measuring, by an electrode connected to the bioimpedance measurement device (two electrode elements 5 a and 5 b are attached to the bioimpedance measurement device 5; [0049]) and based on the first frequency, an extracellular impedance of the patient during a treatment (The ECV(t) value is determined by exploiting the fact that the electrical impedance of body tissue changes as currents of different alternating frequencies are applied to the patient via the electrodes. At low frequencies the cells behave as insulators and the applied current passes only through the ECV spaces; [0050]);
generating, by the bioimpedance measurement device, a second, higher frequency (The means 5 is a bioimpedance measurement device…each of the electrode units 5 a and 5 b consists of a current injection electrode and a potential pick up electrode…currents of different alternating frequencies are applied to the patient via the electrodes; [0049-0050]);
measuring, by an electrode connected to the bioimpedance measurement device (two electrode elements 5 a and 5 b are attached to the bioimpedance measurement device 5; [0049]) and based on the second, higher frequency, an intracellular impedance of the patient during the treatment (At high frequencies the cells become conductive and thus current passes through both the ICV and ECV spaces. This is illustrated in FIG. 4; [0050]) at the same time that the extracellular impedance is measured (As indicated above the ICV(t) and ECV(t) values can be determined simultaneously by the same measurement process; [0020]; Measurement of the impedance over at least two frequencies, better over a range of frequencies, allows an impedance locus to be constructed from which the resistance of the ICV and ECV components may be determined; [0050]); and
determining a dry weight of the patient during the treatment based on the first frequency and the second, higher frequency (the microprocessor program derives the dry weight Wgt dry(t) as follows according to the invention: The extracellular water volume ECV(t) of the patient at the time t is determined and entered into the input unit 2 which passes the value to the computer storage unit 3 where it is stored…the function derived from the stored ECV(t) and Wgt(t) values reflects the fact that these values can only change in a particular manner in the predicted progress of dialysis therapy; [0047-0048]; A first procedure according to which the program stored in the microprocessor program storage unit 1 a derives the dry weight Wgtdry(t) is illustrated in FIG. 5a: In this figure the reference relation between the ECV and Wgtdry for healthy subjects is given as a straight line with slope αe according to equation (8). A single Wgt(t) and ECV(t) measurement of a dialysis patient is denoted by the offline circle. The program for deriving the dry weight Wgtdry(t) of the dialysis patient is now using equation (1) to derive Wgtdry(t). This equation represents the calculation of the intersection IS of a line through the Wgt(t)/ECV(t) data point with the reference line. This line has the slope βe. This slope is expected to be close to 1/ρe, i.e. in a first estimate the program uses βe=1 litre/kg. The weight coordinate of the intersection directly gives the sought Wgtdry(t) value; [0056]; The method which is used by the program stored in the microprocessor program storage unit 1 a to derive the dry weight Wgtdry(t) according to the fourth embodiment is illustrated in FIG. 7 where both a previously established ECV against Wgtdry reference relation and a previously established ICV against Wgtdry reference relation representing healthy subjects are shown. The shown relations simply correspond to equations (8) and (9), i.e. they are given by straight lines with slopes αe and αi, respectively…in the mode shown in FIG. 7 these function are taken as straight lines with slopes βe and βi. Similar to the derivation of equation (1) βi is set to 0 litres/kg; [0073-0075]).
Chamney fails to specifically disclose determining, during the treatment, an impedance curve at the first frequency; determining, during the treatment, an impedance curve at the second, higher frequency; and determining a dry weight of the patient during the treatment based on a flattening of the impedance curves at the first frequency and the second, higher frequency.
In a similar technical field, Zhu teaches a device and method for the determination of dry weight by continuous measurement of resistance and calculation of circumference in a body segment using segmental bioimpedance analysis (Abstract), comprising: determining, during the treatment, an impedance curve (The present invention segmental bioimpedance is continuously measured in a body segment during hemodialysis…multiple resistivity data points are obtained over time, a curve is derived…bioimpedance is measured at the start and end of the dialysis treatment, periodically, during most or all of the dialysis treatment; [0047-0049]) at the first frequency (The measured resistivity of the body segment depends on a number of factors including the frequency of the injected current and the body mass index (BMI). Preferably a single frequency, and optionally multiple frequencies (multi-frequencies) are used. Injected frequencies from about 1 kHz to about 1000 kHz, more preferably from about 1 kHz to about 50 kHz, most preferably from about 1 kHz to about 10 kHz are utilized; [0036-0037]);
determining, during the treatment, an impedance curve (The present invention segmental bioimpedance is continuously measured in a body segment during hemodialysis…multiple resistivity data points are obtained over time, a curve is derived…bioimpedance is measured at the start and end of the dialysis treatment, periodically, during most or all of the dialysis treatment, optionally from about every 10 minutes to about every 20 minutes; [0047-0049]) at the second, higher frequency (optionally multiple frequencies (multi-frequencies) are used. Injected frequencies from about 1 kHz to about 1000 kHz, more preferably from about 1 kHz to about 50 kHz, most preferably from about 1 kHz to about 10 kHz are utilized; [0036-0037]; Examiner’s Note: If multiple frequencies are used, there will be at least two different frequencies, and one will be greater than the other; therefore, there will be a second, higher frequency used for subsequent measurements); and
determining a dry weight of the patient during the treatment based on a flattening of the impedance curves at the first frequency and the second, higher frequency (Multiple resistivity data points are obtained over time, a curve is derived, and the slope of the curve determined. The slope of the curve approaching zero indicates that a substantially constant resistivity has been achieved, thereby reflecting that dry weight has been substantially attained. As the resistivity curve slope approaches zero, the hydration status of the patient approaches dry weight; [0048]; the curve of continuous measurement of the λ(t) function is “flattening”…according to the criteria of dry weight, if the curve of R0/Rt (i.e., λ(t)) flattens, then the calculated slope should be equal to, for example, 0.01/20 min=0.0005/min; [0064-0065]; FIGS. 9 and 10 show exemplary embodiments of the present invention wherein the dry weight is determined from a graph of R0/Rt as a function of time (i.e., λ(t)). In FIG. 9, the dry weight of a patient is indicated by point B (200 minutes), wherein λ(180 min)-λ(200 min)<0.01 over the time interval tm=20 min, and ρN(t)≧ρN,H(20×10−2 Ωm3/kg). In FIG. 10, in; [0078-0079]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have incorporated the flattening curve teachings of Zhu into the invention of Chamney because the slope of the curve approaching zero indicates that a substantially constant resistivity has been achieved, thereby reflecting that dry weight has been substantially attained. As the resistivity curve slope approaches zero, the hydration status of the patient approaches dry weight (Zhu [0048]).
Regarding Claim 2, Chamney discloses wherein determining the dry weight of the patient further comprises determining a ratio of the extracellular impedance at a start of the treatment to the extracellular impedance at a predetermined later time (An even more advantageous embodiment of the invention involves the storage of several ECV(t i) and Wgt(ti) values at times ti, i=1 . . . j, preferably between subsequent dialysis treatments; [0012]; The computer storage unit 3 of the device 10 is hence also able to store Wgt(ti)/ECV(ti) data pairs for various times ti, which are preferably be aquired directly before subsequent dialysis treatments i=1 . . . j, as represented by the measurements shown in FIG. 5b. The program for deriving the dry weight Wgtdry(tj) at the latest time tj is then able to retrieve all Wgt(ti)/ECV(ti) data pairs from the computer storage unit 3; [0058]) during the treatment and determining the dry weight based on the determined ratio (The weight Wgt(t) of the patient at the time t is also determined and processed similarly. The program for deriving the dry weight Wgt dry(t) is capable of calculating an intersection between a function derived from the stored ECV(t) and Wgt(t) values and the previously established ECV against Wgtdry reference line representing healthy subjects according to equation (8); [0048]).
Regarding Claim 3, Chamney fails to disclose wherein the first frequency is 5 kHz and the second, higher frequency is 100 kHz.
In a similar technical field, Zhu teaches a device and method for the determination of dry weight by continuous measurement of resistance and calculation of circumference in a body segment using segmental bioimpedance analysis (Abstract), wherein the first frequency is 5 kHz and the second, higher frequency is 100 kHz (optionally multiple frequencies (multi-frequencies) are used. Injected frequencies from about 1 kHz to about 1000 kHz, more preferably from about 1 kHz to about 50 kHz, most preferably from about 1 kHz to about 10 kHz are utilized; [0036-0037]; Examiner’s Note: Although Zhu does not explicitly disclose wherein the first frequency is 5 kHz and the second higher frequency is 100 kHz, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the multiple frequencies of Zhu from between “about 1 kHz to about 1000 kHz, more preferably from about 1 kHz to about 50 kHz, most preferably from about 1 kHz to about 10 kHz” to 5 kHz and 100 kHz, since it has been held that “[i]n the case where the claimed ranges ‘overlap or lie inside ranges disclosed by the prior art’ a prima facie case of obviousness exists.” In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). Further, although Applicant recites using “5 kHz” and “100 kHz” during the measurement process (see [0029-0031] of the Applicant’s Specification), Applicant merely discloses that the monitor generates these two frequency signals, but appears to have placed no criticality on the claimed range).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have incorporated the frequency teachings of Zhu into the invention of Chamney as the frequency range is fit to a known mathematical model of biological tissue.
Regarding Claim 4, Chamney discloses adhering an electrode array to the patient to measure the extracellular impedance and the intracellular impedance (two electrode elements 5 a and 5 b are attached to the bioimpedance measurement device 5. Each of the electrode units 5 a and 5 b consists of a current injection electrode and a potential pick up electrode (not shown). By applying the two electrode units 5 a and 5 b to the wrist and the ankle of a patient, respectively, as outlined in FIG. 3a, the wholy body impedance may be determined; [0049]).
Regarding Claim 5, Chamney discloses wherein the treatment is dialysis (The invention is based on the observation that dialysis patients have an expanded ECV and that therefore the measured ECV must be higher for a given weight than for healthy subjects. If the weight of a fluid overloaded dialysis patient is reduced over many treatments by removal of fluid then the measured ECV should fall, too. Eventually the ECV of the dialysis patient should converge to or close to that of a healthy subject with no renal failure; [0045]; The function derived from the stored ECV(t) and Wgt(t) values reflects the fact that these values can only change in a particular manner in the predicted progress of dialysis therapy; [0048]).
Regarding Claim 6, Chamney discloses a method for assessing hydration for a patient using multiple frequency bioimpedance measurements (Method and a device for determining the dry weight of a patient with kidney failure; Abstract), the method comprising:
generating, by a bioimpedance measurement device, a first frequency (The means 5 is a bioimpedance measurement device…each of the electrode units 5 a and 5 b consists of a current injection electrode and a potential pick up electrode…currents of different alternating frequencies are applied to the patient via the electrodes; [0049-0050]);
measuring, by an electrode connected to the bioimpedance measurement device (two electrode elements 5 a and 5 b are attached to the bioimpedance measurement device 5; [0049]) and based on the first frequency, an extracellular impedance of the patient during a treatment (The ECV(t) value is determined by exploiting the fact that the electrical impedance of body tissue changes as currents of different alternating frequencies are applied to the patient via the electrodes. At low frequencies the cells behave as insulators and the applied current passes only through the ECV spaces; [0050]);
generating, by a bioimpedance measurement device, a second, higher frequency (The means 5 is a bioimpedance measurement device…each of the electrode units 5 a and 5 b consists of a current injection electrode and a potential pick up electrode…currents of different alternating frequencies are applied to the patient via the electrodes; [0049-0050]);
measuring, by an electrode connected to the bioimpedance measurement device (two electrode elements 5 a and 5 b are attached to the bioimpedance measurement device 5; [0049]) and based on the second, higher frequency, an intracellular impedance of the patient during the treatment (At high frequencies the cells become conductive and thus current passes through both the ICV and ECV spaces. This is illustrated in FIG. 4; [0050]) at the same time that the extracellular impedance is measured (As indicated above the ICV(t) and ECV(t) values can be determined simultaneously by the same measurement process; [0020]; Measurement of the impedance over at least two frequencies, better over a range of frequencies, allows an impedance locus to be constructed from which the resistance of the ICV and ECV components may be determined. Hence the volumes of the respective compartments can then be calculated from the resistance information, based on compartment resistivity constants available from prior studies for which the volumes were also determined by dilution measurements; [0050]);
measuring a resistivity of the patient using each of the first frequency and the second, higher frequency (Measurement of the impedance over at least two frequencies, better over a range of frequencies, allows an impedance locus to be constructed from which the resistance of the ICV and ECV components may be determined. Hence the volumes of the respective compartments can then be calculated from the resistance information, based on compartment resistivity constants available from prior studies for which the volumes were also determined by dilution measurements; [0050]); and
determining euvolemia of the patient during the treatment (the microprocessor program derives the dry weight Wgt dry(t) as follows according to the invention: The extracellular water volume ECV(t) of the patient at the time t is determined and entered into the input unit 2 which passes the value to the computer storage unit 3 where it is stored…the program for deriving the dry weight Wgt dry(t) is capable of calculating an intersection between a function derived from the stored ECV(t) and Wgt(t) values and the previously established ECV against Wgtdry reference line representing healthy subjects according to equation (8); [0047-0048]; Examiner’s Note: Euvolemia is the state where the body’s total fluid volume is at a normal healthy level, and dry weight is the specific weight a person reaches when they are euvolemic; therefore, the determination of dry weight would be the equivalent to determination of euvolemia).
Chamney fails to specifically disclose determining euvolemia of the patient during the treatment based on when the resistivity at the first frequency and the second, higher frequency are both in the normal range.
In a similar technical field, Zhu teaches a device and method for the determination of dry weight by continuous measurement of resistance and calculation of circumference in a body segment using segmental bioimpedance analysis (Abstract), comprising: determining euvolemia of the patient during the treatment based on when the resistivity at the first frequency and the second, higher frequency (optionally multiple frequencies (multi-frequencies) are used. Injected frequencies from about 1 kHz to about 1000 kHz, more preferably from about 1 kHz to about 50 kHz, most preferably from about 1 kHz to about 10 kHz are utilized; [0036-0037]; Examiner’s Note: If multiple frequencies are used, there will be at least two different frequencies, and one will be greater than the other; therefore, there will be a second, higher frequency used for subsequent measurements) are both in the normal range (To measure resistivity, current is injected into the body segment through injector electrodes and the current transmitted through the body segment is received by the measurement electrodes and transmitted to the BIA measurement unit for calculation of the resistivity of the body segment…to obtain a range of normal resistivity values, the bioimpedance of healthy subjects is measured repeatedly at specific body segments, which may be the whole body, preferably a limb segment, more preferably a leg or an arm segment, most preferably a calf segment, over about 15 minute periods. From these values, a set of normal resistivity values is derived that correlates with dry weights. Preferably a large group of healthy subjects is studied to produce a set of normal resistivity values for a specific population. Optionally, determination of resistivity in subsets of the healthy population can be performed in order to more precisely correlate resistivity values with a dialysis patient's dry weight...at any particular time point, the resistivity of the dialysis patient's body segment is compared to the resistivity of the equivalent body segment in healthy subjects, in order to determine the patient's hydration status. When the resistivity of the dialysis patient's body segment is substantially equal to the resistivity in normal subjects, the dialysis patient is determined to be substantially at dry weight, and preferably the patient's body weight is measured; [0050-0052]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have incorporated the normal range resistivity teachings of Zhu into the invention of Chamney in order to determine the patient's hydration status. When the resistivity of the dialysis patient's body segment is substantially equal to the resistivity in normal subjects, the dialysis patient is determined to be substantially at dry weight (Zhu [0052]).
Regarding Claim 7, Chamney discloses wherein determining euvolemia of the patient further comprises determining a ratio of the extracellular impedance at a start of the treatment to the extracellular impedance at a predetermined later time (An even more advantageous embodiment of the invention involves the storage of several ECV(t i) and Wgt(ti) values at times ti, i=1 . . . j, preferably between subsequent dialysis treatments; [0012]; The computer storage unit 3 of the device 10 is hence also able to store Wgt(ti)/ECV(ti) data pairs for various times ti, which are preferably be aquired directly before subsequent dialysis treatments i=1 . . . j, as represented by the measurements shown in FIG. 5b. The program for deriving the dry weight Wgtdry(tj) at the latest time tj is then able to retrieve all Wgt(ti)/ECV(ti) data pairs from the computer storage unit 3; [0058]) during the treatment and determining the dry weight based on the determined ratio (The weight Wgt(t) of the patient at the time t is also determined and processed similarly. The program for deriving the dry weight Wgt dry(t) is capable of calculating an intersection between a function derived from the stored ECV(t) and Wgt(t) values and the previously established ECV against Wgtdry reference line representing healthy subjects according to equation (8); [0048]).
Regarding Claim 8, Chamney fails to disclose wherein the first frequency is 5 kHz and the second, higher frequency is 100 kHz.
In a similar technical field, Zhu teaches a device and method for the determination of dry weight by continuous measurement of resistance and calculation of circumference in a body segment using segmental bioimpedance analysis (Abstract), wherein the first frequency is 5 kHz and the second, higher frequency is 100 kHz (optionally multiple frequencies (multi-frequencies) are used. Injected frequencies from about 1 kHz to about 1000 kHz, more preferably from about 1 kHz to about 50 kHz, most preferably from about 1 kHz to about 10 kHz are utilized; [0036-0037]; Examiner’s Note: Although Zhu does not explicitly disclose wherein the first frequency is 5 kHz and the second higher frequency is 100 kHz, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the multiple frequencies of Zhu from between “about 1 kHz to about 1000 kHz, more preferably from about 1 kHz to about 50 kHz, most preferably from about 1 kHz to about 10 kHz” to 5 kHz and 100 kHz, since it has been held that “[i]n the case where the claimed ranges ‘overlap or lie inside ranges disclosed by the prior art’ a prima facie case of obviousness exists.” In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). Further, although Applicant recites using “5 kHz” and “100 kHz” during the measurement process (see [0029-0031] of the Applicant’s Specification), Applicant merely discloses that the monitor generates these two frequency signals, but appears to have placed no criticality on the claimed range).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have incorporated the frequency teachings of Zhu into the invention of Chamney as the frequency range is fit to a known mathematical model of biological tissue.
Regarding Claim 9, Chamney discloses adhering an electrode array to the patient to measure the extracellular impedance and the intracellular impedance (two electrode elements 5 a and 5 b are attached to the bioimpedance measurement device 5. Each of the electrode units 5 a and 5 b consists of a current injection electrode and a potential pick up electrode (not shown). By applying the two electrode units 5 a and 5 b to the wrist and the ankle of a patient, respectively, as outlined in FIG. 3a, the wholy body impedance may be determined; [0049]).
Regarding Claim 10, Chamney discloses wherein the treatment is dialysis (The invention is based on the observation that dialysis patients have an expanded ECV and that therefore the measured ECV must be higher for a given weight than for healthy subjects. If the weight of a fluid overloaded dialysis patient is reduced over many treatments by removal of fluid then the measured ECV should fall, too. Eventually the ECV of the dialysis patient should converge to or close to that of a healthy subject with no renal failure; [0045]; The function derived from the stored ECV(t) and Wgt(t) values reflects the fact that these values can only change in a particular manner in the predicted progress of dialysis therapy; [0048]).
Regarding Claim 18, although Chamney discloses measuring a resistivity of the patient using each of the first frequency and the second, higher frequency (Measurement of the impedance over at least two frequencies, better over a range of frequencies, allows an impedance locus to be constructed from which the resistance of the ICV and ECV components may be determined. Hence the volumes of the respective compartments can then be calculated from the resistance information, based on compartment resistivity constants available from prior studies for which the volumes were also determined by dilution measurements; [0050]), Chamney fails to specifically disclose wherein determining the dry weight further comprises determining the dry weight when the resistivity at the first frequency and the second, higher frequency are both in the normal range.
In a similar technical field, Zhu teaches a device and method for the determination of dry weight by continuous measurement of resistance and calculation of circumference in a body segment using segmental bioimpedance analysis (Abstract), wherein determining the dry weight further comprises determining the dry weight when the resistivity at the first frequency and the second, higher frequency (optionally multiple frequencies (multi-frequencies) are used. Injected frequencies from about 1 kHz to about 1000 kHz, more preferably from about 1 kHz to about 50 kHz, most preferably from about 1 kHz to about 10 kHz are utilized; [0036-0037]; Examiner’s Note: If multiple frequencies are used, there will be at least two different frequencies, and one will be greater than the other; therefore, there will be a second, higher frequency used for subsequent measurements) are both in the normal range (To measure resistivity, current is injected into the body segment through injector electrodes and the current transmitted through the body segment is received by the measurement electrodes and transmitted to the BIA measurement unit for calculation of the resistivity of the body segment…to obtain a range of normal resistivity values, the bioimpedance of healthy subjects is measured repeatedly at specific body segments, which may be the whole body, preferably a limb segment, more preferably a leg or an arm segment, most preferably a calf segment, over about 15 minute periods. From these values, a set of normal resistivity values is derived that correlates with dry weights. Preferably a large group of healthy subjects is studied to produce a set of normal resistivity values for a specific population. Optionally, determination of resistivity in subsets of the healthy population can be performed in order to more precisely correlate resistivity values with a dialysis patient's dry weight...at any particular time point, the resistivity of the dialysis patient's body segment is compared to the resistivity of the equivalent body segment in healthy subjects, in order to determine the patient's hydration status. When the resistivity of the dialysis patient's body segment is substantially equal to the resistivity in normal subjects, the dialysis patient is determined to be substantially at dry weight, and preferably the patient's body weight is measured; [0050-0052]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have incorporated the normal range resistivity teachings of Zhu into the invention of Chamney in order to determine the patient's hydration status. When the resistivity of the dialysis patient's body segment is substantially equal to the resistivity in normal subjects, the dialysis patient is determined to be substantially at dry weight (Zhu [0052]).
Regarding Claim 19, Chamney fails to specifically disclose wherein determining the euvolemia further comprises determining, during the treatment, an impedance curve at the first frequency; determining, during the treatment, an impedance curve at the second, higher frequency; and determining euvolemia of the patient during the treatment based on a flattening of the impedance curves at the first frequency and the second, higher frequency.
In a similar technical field, Zhu teaches a device and method for the determination of dry weight by continuous measurement of resistance and calculation of circumference in a body segment using segmental bioimpedance analysis (Abstract), comprising: determining, during the treatment, an impedance curve (The present invention segmental bioimpedance is continuously measured in a body segment during hemodialysis…multiple resistivity data points are obtained over time, a curve is derived…bioimpedance is measured at the start and end of the dialysis treatment, periodically, during most or all of the dialysis treatment, optionally from about every 10 minutes to about every 20 minutes; [0047-0049]) at the first frequency (The measured resistivity of the body segment depends on a number of factors including the frequency of the injected current and the body mass index (BMI). Preferably a single frequency, and optionally multiple frequencies (multi-frequencies) are used. Injected frequencies from about 1 kHz to about 1000 kHz, more preferably from about 1 kHz to about 50 kHz, most preferably from about 1 kHz to about 10 kHz are utilized; [0036-0037]);
determining, during the treatment, an impedance curve (The present invention segmental bioimpedance is continuously measured in a body segment during hemodialysis…multiple resistivity data points are obtained over time, a curve is derived…bioimpedance is measured at the start and end of the dialysis treatment, periodically, during most or all of the dialysis treatment, optionally from about every 10 minutes to about every 20 minutes; [0047-0049]) at the second, higher frequency (optionally multiple frequencies (multi-frequencies) are used. Injected frequencies from about 1 kHz to about 1000 kHz, more preferably from about 1 kHz to about 50 kHz, most preferably from about 1 kHz to about 10 kHz are utilized; [0036-0037]; Examiner’s Note: If multiple frequencies are used, there will be at least two different frequencies, and one will be greater than the other; therefore, there will be a second, higher frequency used for subsequent measurements); and
determining euvolemia of the patient during the treatment based on a flattening of the impedance curves at the first frequency and the second, higher frequency (Multiple resistivity data points are obtained over time, a curve is derived, and the slope of the curve determined. The slope of the curve approaching zero indicates that a substantially constant resistivity has been achieved, thereby reflecting that dry weight has been substantially attained. As the resistivity curve slope approaches zero, the hydration status of the patient approaches dry weight; [0048]; the curve of continuous measurement of the λ(t) function is “flattening”…according to the criteria of dry weight, if the curve of R0/Rt (i.e., λ(t)) flattens, then the calculated slope should be equal to, for example, 0.01/20 min=0.0005/min; [0064-0065]; FIGS. 9 and 10 show exemplary embodiments of the present invention wherein the dry weight is determined from a graph of R0/Rt as a function of time (i.e., λ(t)). In FIG. 9, the dry weight of a patient is indicated by point B (200 minutes), wherein λ(180 min)-λ(200 min)<0.01 over the time interval tm=20 min, and ρN(t)≧ρN,H(20×10−2 Ωm3/kg). In FIG. 10, in; [0078-0079]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have incorporated the flattening curve teachings of Zhu into the invention of Chamney because the slope of the curve approaching zero indicates that a substantially constant resistivity has been achieved, thereby reflecting that dry weight has been substantially attained. As the resistivity curve slope approaches zero, the hydration status of the patient approaches dry weight (Zhu [0048]).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHANEL J YOON whose telephone number is (571) 272-2695. The examiner can normally be reached on Monday-Friday 9:00AM-5:00PM.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Alexander Valvis can be reached on 571-272-4233. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see https://ppair-my.uspto.gov/pair/PrivatePair. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/CHANEL J YOON/Examiner, Art Unit 3791
