Ex Parte Mahajan et al

Patent Trial and Appeal Board

Dec 19, 2012

11198561 (P.T.A.B. Dec. 19, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte AJAY MAHAJAN and SUMEER LAL
____________

Appeal 2010-008922
Application 11/198,561
Technology Center 3700
____________

Before STEVEN D.A. McCARTHY, GAY ANN SPAHN, and
JOHN W. MORRISON, Administrative Patent Judges.

SPAHN, Administrative Patent Judge.

DECISION ON APPEAL

STATEMENT OF THE CASE
Ajay Mahajan and Sumeer Lal (Appellants) seek our review under 35
U.S.C. § 134 of the Examiner’s rejection of claims 1, 2, 4-11, and 13-20.
Appellants cancelled claims 3 and 12. We have jurisdiction under 35 U.S.C.
§ 6(b).
We REVERSE.

Appeal 2010-008922
Application 11/198,561

2
The Claimed Subject Matter
Claims 1, 10, and 20 are independent and claim 1, reproduced below,
with emphasis added, is illustrative of the subject matter on appeal.
1. A method for facilitating surgery, the method
comprising the acts of:
transmitting a first signal from a first transmitter coupled
to a surgical probe;
receiving the first signal at a plurality of receivers
including a first receiver and a second receiver;
determining an estimate of a position of a portion of the
surgical probe based on the first signal received by the plurality
of receivers including:
determining a first time difference between a time
at which the first signal is received by the first receiver
and a time at which the first signal is received by the
second receiver, and
determining the estimate of the position based on
the first time difference;
wherein the method further comprises displaying an
indication of the estimate of the position on a display unit,
wherein the display unit displays a representation of an
anatomy of a patient, and wherein the indication of the estimate
of the position is integrated with the representation of the
anatomy of the patient.

The Rejections
The following Examiner’s rejections are before us for review:
I. claims 1, 2, 7, 8, 10, 11, 13-15, 17, 18, and 20 under 35 U.S.C.
§ 102(b) as anticipated by Vesely (US 6,246,898 B1, issued Jun. 12, 2001);
II. claims 4-6 under 35 U.S.C. § 103(a) as unpatentable over
Vesely;
Appeal 2010-008922
Application 11/198,561

3
III. claims 9 and 16 under 35 U.S.C. § 103(a) as unpatentable over
Vesely and Sharf (US 2004/0236193 A1, published Nov. 25, 2004); and
IV. claim 19 under 35 U.S.C. § 103(a) as unpatentable over Vesely
and Martin (US 4,802,487, issued Feb. 7, 1989).

OPINION
Rejection I – Anticipation based on Vesely
The Examiner finds that Vesely discloses each and every limitation to
anticipate independent claims 1, 10, and 20. Ans. 3-4. In particular, the
Examiner finds that Vesely discloses “determining a first time difference
between a time at which the first signal is received by the first receiver and a
time at which the first signal is received by the second receiver,” and
“determining the estimate of [the] position [of a portion of the surgical
probe] based on the first time difference.” Ans. 4 (citing Vesely, col. 12, l.
58 to col. 13, l. 7, col. 14, ll. 50-55, and col. 15, ll. 1-10). Emphasis omitted.
Appellants argue that “Vesely does not disclose or suggest using a
time difference between a time at which a signal is received by a first
receiver and a time at which the signal is received by a second receiver to
determine an estimate of a position of a surgical probe.” App. Br. 8.1
Appellants refer to Vesely’s disclosure “that ‘[b]oth time of flight and phase
relationships may be used to determine distance.’” Id (quoting Vesely, col.
13, ll. 6-7). Appellants assert that “Vesely describes using the transit time

1 Appellants do not have page numbers on any of the 14 pages of the Appeal
Brief; however, we number the page beginning with the caption “IN THE
UNITED STATES PATENT AND TRADEMARK OFFICE” page 1,
and we number each consecutive page thereafter with pages 2 through 14,
respectively.
Appeal 2010-008922
Application 11/198,561

4
(or propagation delay) of a signal traveling from a first transducer (acting as
a transmitter) to a second transducer, and then using that transit time to
calculate the distance between the pair of transducers” and “[t]he distances
between each pair of transducers in then used to determine positions of the
transducers.” Id. Appellants assert that Vesely alternatively describes “a
technique in which a difference between a phase at a transmitter and a phase
at a receiver is utilized to determine a distance between the transmitter and
the receiver.” App. Br. 9. Emphasis omitted. Appellants argue that neither
Vesely’s use of time of flight nor phase relationships satisfies the
requirement of claims 1, 10, and 20 that the time difference between a time
at which the first signal is received by the first and second receiver is used to
determine an estimate of the position of the surgical probe. Id.
The Examiner responds that Appellants allege “Vesely teaches 3D
tracking for medical procedures where a plurality of mobile transducers
fitted to a catheter are exclusively paired with a respective one of a plurality
of reference transducers” so that Vesely “merely determines the distance
between a single combination of transducers.” Ans. 7-8. It is the
Examiner’s position that Vesely teaches 3D triangulation requiring at least 4
transducers detecting signals from a single transmitter so that time of flight
information from all combinations of transducers is measured and the
distance between any combination of two transducers is determined by
having each transducer send a signal to all other transducers. Ans. 8-9.
Appellants reply that the Examiner has misinterpreted what
Appellants are arguing. Reply Br. 4. Appellants assert that they are not
arguing that Vesely fails to determine “respective distances between all
combinations of pairs of transducers” as the Examiner suggests. Id. Rather,
Appeal 2010-008922
Application 11/198,561

5
Appellants are arguing that Vesely does not anticipate claims 1, 10, and 20,
because Vesely uses time of flight, i.e., the time it takes a signal to travel
from a transmitter to a receiver, to calculate distances which are then used to
calculate locations of the transducers, whereas the present invention uses
time difference, i.e., the difference between the time at which the first signal
is received by the first and second receiver, to attain greater accuracy in the
determination of an estimate of the position of the surgical probe. Reply Br.
4-5.
We are persuaded by Appellants’ arguments that Vesely does not
anticipate independent claims 1, 10, and 20. Vesely discloses using time of
flight between pairs of transducers, not time difference between first and
second transducers receiving the same signal, to determine distance. Vesely,
col. 13, ll. 6-7. Indeed, Vesely discloses that a first transducer transmits
signals in the form of an ultrasound pulse to second and third transducers
which each receive a different signal from the first transducer to calculate a
respective distance to the first transducer. Vesely, col. 13, ll, 28-41 and 51-
56, col. 14, ll. 50-55, and col. 15, ll. 4-5. Then, using similarly calculated
distances between each pair of transducers, Vesely determines the location
of the first, second, and third transducers relative to a reference transducer.
Vesely, col. 13, ll. 41-42. As the Examiner has failed to show by a
preponderance of the evidence that Vesely discloses using time difference
between when first and second receivers receive the same signal from a
transmitter to determine an estimate of a position, we do not sustain the
Examiner’s rejection of independent claims 1, 10, and 20, and claims 2, 7, 8,
11, 13-15, 17 and 18 dependent thereon, under 35 U.S.C. § 102(b) as
anticipated by Vesely.
Appeal 2010-008922
Application 11/198,561

6
Rejections II-IV – Obviousness based on Vesely alone
or in combination with either Sharf or Martin, respectively
The Examiner’s obviousness rejections rely on the erroneous finding
that Vesely discloses using the time difference between receipt of a signal by
first and second receivers to determine an estimate of the position of a
surgical probe. Ans. 5-6. Appellants make the same arguments as discussed
supra with respect to the anticipation of independent claims 1 and 10 based
on Vesely, and Appellants also argue that neither Sharf nor Martin cure the
deficiencies of Vesely. App. Br. 12-13. We are persuaded by Appellants’
arguments, and for the same reasons as discussed supra, we do not sustain
the Examiner’s rejections, under 35 U.S.C. § 103(a), of: claims 4-6 as
unpatentable over Vesely; claims 9 and 16 as unpatentable over Vesely and
Sharf; and claim 19 as unpatentable over Vesely and Martin.

DECISION
We reverse the Examiner’s decision to reject claims 1, 2, 4-11, and
13-20.

REVERSED

mls