Ex Parte Armstrong et al

Patent Trial and Appeal Board

Oct 31, 2012

11457033 (P.T.A.B. Oct. 31, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
11/457,033 07/12/2006 Randolph K. Armstrong 1000.148 6542
7590 11/01/2012
Timothy L. Scott
100 Cyberonics Blvd
Houston, TX 77058
EXAMINER
PORTER, JR, GARY A
ART UNIT PAPER NUMBER
3766
MAIL DATE DELIVERY MODE
11/01/2012 PAPER
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________________

Ex parte RANDOLPH K. ARMSTRONG and SCOTT A. ARMSTRONG
____________________

Appeal 2010-004628
Application 11/457,033
Technology Center 3700
____________________

Before EDWARD A. BROWN, MICHELLE R. OSINSKI, and
SCOTT E. KAMHOLZ, Administrative Patent Judges.

BROWN, Administrative Patent Judge.

DECISION ON APPEAL
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Application 11/457,033

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STATEMENT OF THE CASE
Appellants appeal under 35 U.S.C. § 134(a) from the Examiner's
decision rejecting claims 1-22. (App. Br. 5). We have jurisdiction over this
appeal under 35 U.S.C. § 6(b).
We AFFIRM-IN-PART.
THE CLAIMED SUBJECT MATTER
Independent claim 1, reproduced below, is illustrative:
1. A method for charge balance assessment in
an implantable medical device, the method
comprising:
delivering, via a current source, at least one
electrical signal to tissue of a patient through an
electrode; and
assessing, via a charge balance
determination unit, whether a net charge remains
on the electrode a predetermined period of time
after the delivery of the electrical signal;
wherein said predetermined period of time is
at least one hour.
THE REJECTIONS
Appellants request review of the following rejections:1
1. Claims 1-9 and 11-18 under 35 U.S.C. § 103(a) as unpatentable
over Zeijlemaker.2
2. Claims 10, 19, and 20 under 35 U.S.C. § 103(a) over
Zeijlemaker and Whigham (US 4,903,700; iss. Feb. 27, 1990).

1 The Examiner withdrew the rejection of claims 1-9 and 11-18 under 35
U.S.C. § 102(e) as anticipated by Zeijlemaker (US 2006/0224199 A1; pub.
Oct. 5, 2006). (Ans. 13-14).
2 Appellants correctly note that the Examiner's stated reasons for this
rejection also address claims 21 and 22. (App. Br. 9; Ans. 12). We treat
claims 21 and 22 as also being subject to this ground of rejection.
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Application 11/457,033

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ANALYSIS
Claims 1-9, 11-18, 21, and 22 – Zeijlemaker
Claims 1-9, 21, and 22
The Examiner found Zeijlemaker discloses a method for charge
balance assessment in an implantable device, comprising, inter alia, the
determination of residual charge (remaining on an electrode) and elimination
of the artifact (i.e., polarization artifact) on the electrode occurring over "a
very short period of time, i.e. 10 ms (Fig. 7)." (Ans. 8). The Examiner
found Zeijlemaker does not disclose "assessing after an hour whether a net
charge remains on the electrode," but found that Appellants' Specification
states, "more generally, a 'predetermined period of time' can be any time
period subsequent to the completion of delivery of the electrical signal . . . ."
(Ans. 8) (citing Spec. para. [0034]). The Examiner concluded that it would
have been an obvious matter of design choice to one of ordinary skill in the
art to determine the residual charge left on the electrode an hour after the
initial stimulus. (Ans. 8-9). The Examiner stated that one of ordinary skill
in the art "would have expected Zeijlemaker's artifact elimination circuit
and Appellant's invention to perform equally well with either the 10 ms time
period taught by Zeijlemaker or the claimed 1 hour time period because both
time periods would perform the same function of eliminating residual charge
on a stimulation electrode." (Ans. 9) (emphasis added).
Appellants contend that they address the problem of "net charge
build-up on the electrodes that occurs over a long period of time," whereas
the purpose of Zeijlemaker is "instantaneous polarization reduction for
sensing the evoked response that should occur almost immediately after the
stimulus." (App. Br. 11). Appellants contend Zeijlemaker must eliminate
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Application 11/457,033

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polarization very quickly after the stimulus (pacing pulse) before the evoked
response, so that the evoked response can be sensed. (Id.). Appellants
contend that the recited time period of "at least one hour" would not permit
Zeijlemaker's device to achieve its intended functionality, and waiting this
long to assess charge for Zeijlemaker's device would render it unsuitable for
is intended purpose. (Id. at 11-12).
Appellants' contentions are persuasive. Zeijlemaker discloses
delivering a pacing (stimulation) pulse 120 to the heart, and then providing a
recharge pulse 122 to minimize a pace polarization artifact 124, which is
created by the pacing pulse 120 at the electrode – tissue interface and stored
on the stimulating electrode. (See Zeijlemaker, para. [0062], Figs. 6, 7).
Zeijlemaker also discloses:
Following a predetermined delay 126 after
termination of the recharge pulse 122, a sample
amplitude 128 of the pace polarization artifact 124
remaining on the electrode is measured by the
IMD 10, represented in step 102 of FIG. 6. Such
sampling is conducted as soon as possible after
termination of the recharge pulse 122 and
restoration of normal gain. Such prompt sampling
provides a significant sampling of the pace
polarization artifact 124, and in tum, a good
estimate for compensating a subsequent recharge
pulse (if warranted), leading to reduction of a
subsequent pace polarization artifact created by a
subsequent pacing pulse. As shown, the sample
amplitude 128 is taken after the predetermined
delay 126. The sampling delay 126 is generally a
characteristic of the electronics utilized, and such
delay 126 is generally minimized when possible.
One reason for minimizing the delay 126 lies in
the nature of the cardiac condition that is being
treated by the IMD 10.
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(Zeijlemaker, para. [0064]) (emphasis added).
Although Appellants' Specification discloses that a "predetermined
period of time" is not limited to a particular period of time subsequent to the
completion of delivery of the electrical signal, claim 1 requires that the
"predetermined period of time is at least one hour." The Examiner did not
provide an adequate reason with a rational underpinning why one of
ordinary skill in the art would have modified Zeijlemaker's method of
reducing polarization on an implanted electrode by assessing whether a net
charge remains on the electrode, to use a sampling delay of at least one hour
after the delivery of the pacing pulse. Accordingly, we do not sustain the
rejection of claim 1, or claims 2-9, 21, and 22 which depend therefrom.
Claims 11-18
Independent claim 11 is directed to a system comprising, inter alia, "a
charge balance determination unit that detects whether a net charge remains
on the electrode a predetermined period of time after the electrical signal is
delivered," "wherein said predetermined period of time is at least one hour."
While Zeijlemaker discloses a method of reducing polarization on an
implanted electrode using a delay that is minimized when possible,
Appellants have not provided any persuasive argument or evidence showing
that the charge balance determination unit of Zeijlemaker's system is
incapable of detecting whether a net charge remains on the electrode at least
one hour after an electrical signal is delivered. Accordingly, we sustain the
rejection of claim 11.
Appellants have not provided any separate argument for claims 12-14
and 16-18, which depend from claim 11. We also sustain the rejection of
these dependent claims.
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Claim 15 depends from claim 11 and recites that the charge balance
determination unit comprises "a resistance coupling the electrode to a
reference voltage." The Examiner found that it would have been inherent in
Zeijlemaker that voltage is measured with a resistive element. (Ans. 10).
Appellants contend that Zeijlemaker does not teach use of the resistor as a
component for measuring voltage differential. (App. Br. 12). In response,
the Examiner found that Zeijlemaker's measuring of a polarization artifact
inherently involves measuring a voltage differential across a resistance that
is closely associated with the electrode and a reference voltage, and that this
is a common practice of measuring any voltage in a circuit. (Ans. 16). As
Appellants do not apprise us of any error in these findings, we sustain the
rejection of claim 15.
Claims 10, 19, and 20 – Zeijlemaker and Whigham
Claim 10 depends from claim 1. The Examiner's application of
Whigham with respect to claim 10 (Ans. 12-13) does not cure the
deficiencies of the rejection of claim 1, as discussed supra. We do not
sustain the rejection of claim 10.
Claims 19 and 20 depend from claim 11. Claim 19 recites that the
system further comprises "an external programming device operable to
display a notification to one of the patient and a physician that a net charge
remains on the electrode." Claim 20 also recites an external programming
device. The Examiner found that Zeijlemaker fails to disclose "transmitting
from an IMD to an external device a signal indicative of whether a net
charge remains on the electrode and subsequently altering the stimulation
pulse applied to the body." (Ans. 13). The Examiner found Whigham
discloses an external programmer in communication with an IMD, and
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concluded that it would have been obvious to modify Zeijlemaker's device to
include transmitting a signal indicative of whether a net charge remains on
the electrode from an IMD to an external device and subsequently altering
the stimulation pulse applied to the body for efficiently adjusting the charge
balancing module. (Ans. 13).
Appellants contend that Whigham does not teach or suggest
"transmitting a signal 'indicative of whether a net charge remains on the
electrode.'" (App. Br. 14; see also Reply Br. 3). However, as discussed
supra, the Examiner found that Zeijlemaker discloses determining whether a
net charge remains on an electrode, and relied on Whigham for its teaching
of transmitting externally a signal from an IMD. Appellants' contention
does not persuasively address the Examiner's combination of teachings.
Accordingly, we sustain the rejection of claims 19 and 20.
DECISION
The Examiner's decision rejecting claims 1-10, 21, and 22 is
REVERSED, and rejecting claims 11-20 is AFFIRMED. No time period for
taking any subsequent action in connection with this appeal may be extended
under 37 C.F.R. § 1.136(a). See 37 C.F.R. § 1.136(a)(1)(iv).
AFFIRMED-IN-PART

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