UNITED STATES PATENT AND TRADEMARK OFFICE
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`
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`BEFORE THE PATENT TRIAL AND APPEAL BOARD
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`
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`ELEKTA INC.
`
`Petitioner
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`
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`v.
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`VARIAN MEDICAL SYSTEMS, INC. AND VARIAN MEDICAL SYSTEMS
`INTERNATIONAL AG
`
`Patent Owner
`
`
`
`CASE UNASSIGNED
`Patent No. 7,880,154
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`DECLARATION OF RYAN FLYNN, Ph.D.
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`Page 1 of 123
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`Elekta Exhibit 1002
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`I. 
`
`II. 
`
`TABLE OF CONTENTS
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`Introduction ...................................................................................................... 1 
`
`Qualifications ................................................................................................... 2 
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`III.  Compensation .................................................................................................. 3 
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`IV. 
`
`Information Considered ................................................................................... 3 
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`V.  Anticipation Principles .................................................................................... 4 
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`VI.  Obviousness Principles .................................................................................... 4 
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`VII.  Person of Ordinary Skill in the Art .................................................................. 6 
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`VIII.  Technology Background: Radiation Therapy ................................................. 6 
`
`A. 
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`B. 
`
`Radiation Treatment Machines ............................................................. 7 
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`Radiation Treatment Plans .................................................................. 11 
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`1. 
`
`Intensity-Modulated Radiation Therapy (“IMRT”) .................. 12 
`
`a) 
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`Earl ’261 ......................................................................... 13 
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`2. 
`
`Intensity-Modulated Arc Therapy (“IMAT”) ........................... 15 
`
`a) 
`
`b) 
`
`c) 
`
`d) 
`
`Yu ’902 ........................................................................... 15 
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`Earl Article ...................................................................... 17 
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`Earl ’261 ......................................................................... 18 
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`Duthoy ............................................................................ 19 
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`3. 
`
`Optimization of Treatment Plans .............................................. 20 
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`a) 
`
`Prior Art Techniques to Improve Speed and
`Accuracy of Automated Iterative Optimization of
`Treatment Plans .............................................................. 28 
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`(1)  Multistage or Progressive Approaches to
`Optimization ......................................................... 29 
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`4. 
`
`Delivery of Treatment Plans ..................................................... 31 
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`IX.  Overview of the ’154 Patent .......................................................................... 32 
`
`X. 
`
`Claim Construction ........................................................................................ 36 
`
`A. 
`
`B. 
`
`C. 
`
`“source trajectory direction” [claims 19 and 28] ................................ 37 
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`“leaf-translation direction” [claim 28] ................................................ 37 
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`“arc” [claims 20, 24-26, 34-36] ........................................................... 37 
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`XI.  Claims 19, 20, 23, 24, and 27 are Unpatentable Based on the
`Disclosure of Earl Article and Other Prior Art ............................................. 38 
`
`A. 
`
`Earl Article anticipates claim 19, 20, 23, 24, and 27 .......................... 38 
`
`1. 
`
`2. 
`
`3. 
`
`4. 
`
`Earl Article Discloses Each and Every Element of Claim
`19 ............................................................................................... 38 
`
`Earl Article Discloses Each and Every Element of Claims
`20 and 24 ................................................................................... 44 
`
`Earl Article Discloses Each and Every Element of Claim
`23 ............................................................................................... 45 
`
`Earl Article Discloses Each and Every Element of Claim
`27 ............................................................................................... 46 
`
`B. 
`
`The combination of Earl Article and Tobler renders obvious
`claims 19, 20, 23, 24, and 27 ............................................................... 47 
`
`1. 
`
`Earl Article and Tobler Teach Element [19.e] “wherein
`delivering the treatment radiation beam from the
`treatment radiation source to the subject comprises
`varying an intensity of the treatment radiation beam over
`at least a portion of the trajectory,” as Recited in Claim
`19 ............................................................................................... 50 
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`2. 
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`3. 
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`4. 
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`Earl Article and Tobler Teach Each and Every Element
`of Claims 20 and 24 .................................................................. 51 
`
`Earl Article and Tobler Teach Each and Every Element
`of Claim 23 ................................................................................ 51 
`
`Tobler Provides a Motivation to Combine Earl Article
`and Tobler ................................................................................. 52 
`
`C. 
`
`The combination of Earl Article (or Earl Article and Tobler)
`and Yu renders obvious claims 25 and 26 ........................................... 55 
`
`1. 
`
`Earl Article (or Earl Article in view of Tobler) and Yu
`Collectively Teach Each and Every Element of Claims
`25 and 26 ................................................................................... 56 
`
`a) 
`
`b) 
`
`Earl Article (or Earl Article in view of Tobler) and
`Yu Teach Each and Every Element of Claim 25 ............ 56 
`
`Earl Article (or Earl Article in view of Tobler) and
`Yu Teach Each and Every Element of Claim 26 ............ 59 
`
`2. 
`
`Yu Provides a Motivation to Combine Earl Article or
`Earl Article and Tobler With Yu .............................................. 60 
`
`D. 
`
`The combination of Earl Article (or Earl Article and Tobler)
`and Otto ’530 renders obvious claims 28, 33, and 34 ......................... 63 
`
`1. 
`
`2. 
`
`3. 
`
`4. 
`
`Earl Article (or Earl Article in view of Tobler) and
`Otto ’530 Teach Each and Every Element of Claim 28 ........... 64 
`
`Earl Article (or Earl Article in view of Tobler) and
`Otto ’530 Teach Each and Every Element of Claim 33 ........... 69 
`
`Earl Article (or Earl Article in view of Tobler) and
`Otto ’530 Teach Each and Every Element of Claim 34 ........... 69 
`
`Otto ’530 Provides a Motivation To Combine Earl
`Article (or Earl Article and Tobler) and Otto ’530 ................... 70 
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`E. 
`
`The combination of Earl Article (or Earl Article and Tobler)
`and Otto ’530 and Yu renders obvious claims 35 and 36 .................... 72 
`
`1. 
`
`Earl Article (or Earl Article in view of Tobler), Otto ’530,
`and Yu Collectively Teach Each and Every element of
`Claims 35 and 36....................................................................... 75 
`
`XII.  Conclusion ..................................................................................................... 77 
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`iv
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`I, Dr. Ryan Flynn, declare as follows:
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`I.
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`Introduction
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`1. My name is Ryan Flynn, and I am a clinical associate professor of radiation
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`oncology at the University of Iowa Carver College of Medicine.
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`2.
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`I have been retained by Elekta AB (“Elekta” or “Petitioner”) as an
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`independent expert consultant in this proceeding before the United States Patent
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`and Trademark Office associated with Elekta’s Petition for Inter Partes Review
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`(“Petition”).
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`3.
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`I understand that this proceeding involves U.S. Patent No. 7,880,154
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`(“the ’154 patent”) (attached as Ex. 1001 to Elekta’s Petition).
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`4.
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`5.
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`I understand that Varian Medical Systems owns the ’154 patent.
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`I have been asked to investigate and opine on certain issues relating to
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`the ’154 patent and to consider whether certain references disclose or suggest the
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`features recited in the claims of the ’154 patent. As explained in detail below, in
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`my opinion: Earl Article (Ex. 1009) anticipates claims 19, 20, 23, 24, and 27; the
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`combination of Earl Article and Tobler (Ex. 1027) renders obvious claims 19, 20,
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`23, 24, and 27; the combination of Earl Article or Earl Article in view of Tobler
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`and Yu (Ex. 1008) renders obvious claims 25 and 26; the combination Earl Article
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`or Earl Article in view of Tobler and Otto ’530 (Ex. 1004) renders obvious claims
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`1
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`28, 33, and 34; and the combination of Earl Article or Earl Article in view of
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`Tobler, Otto ’530, and Yu renders obvious claims 35 and 36.
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`II. Qualifications
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`6. My curriculum vitae, which includes a more detailed summary of my
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`background, experience, and publications, is attached as Appendix A.
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`7.
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`I have either trained or worked in the radiotherapy field for approximately
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`14 years. I am the Director of the Medical Physics Division in the Department of
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`Radiation Oncology at the University of Iowa, a position I have held for nearly
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`three years.
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`8.
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`I graduated with my Ph.D. in Medical Physics from the University of
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`Wisconsin in 2007, where I wrote my dissertation on treatment planning
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`optimization and delivery techniques that applied to proton therapy and x-ray
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`therapy, particularly helical tomotherapy. I have authored or co-authored 38 peer-
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`reviewed publications and am a co-inventor of 7 awarded patents with 3 patents
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`pending. I have been a board-certified radiotherapy physicist since 2011. My
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`training, clinical, and management experience qualify me as a person skilled in the
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`art of radiotherapy physics.
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`9.
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`I am not an attorney and offer no legal opinions, but in the course of my
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`work, I have had experience studying and analyzing patents and patent claims from
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`the perspective of a person skilled in the art.
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`2
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`III. Compensation
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`10.
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`I am being compensated at my standard rate of $500 per hour for the time I
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`spend on this matter. No part of my compensation depends on my performance, the
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`outcome of this proceeding, or any issues involved in or related to this inter partes
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`review proceeding.
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`IV.
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`11.
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`Information Considered
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`In forming my opinions, I have relied on the ’154 patent, its prosecution
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`history, and materials cited in Elekta’s Petition that are listed in the attached
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`Appendix B. I have also relied on my own experience and expertise of the
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`knowledge of the person of ordinary skill in the relevant art in the timeframe of
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`July 25, 2005, which I understand is the earliest potential effective filing date of
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`the application that became the ’770 patent.
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`12. This declaration is based on information currently available to me. To the
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`extent additional information becomes available, I reserve the right to continue my
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`investigation and study, which may include a review of documents and information
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`that recently have been or may be produced, as well as testimony from depositions
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`that may be taken after I complete this declaration.
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`13. For convenience, I have included exhibit numbers in this declaration that I
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`understand are the exhibit numbers being used in the Petition.
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`3
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`V. Anticipation Principles
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`14.
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`I understand that for a patent claim to be anticipated under 35 U.S.C. § 102,
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`a single prior art document must disclose, either expressly or inherently, each and
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`every claim limitation. I further understand that to be inherently anticipated, a
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`single prior art document must necessarily and inevitably disclose the claim
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`limitations at issue. For a patent claim to be anticipated under § 102(b), I
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`understand that the claim must have been patented or described in a printed
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`publication in any country, or in public use or on sale in the United States, more
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`than one year prior to the United States patent application date.
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`VI. Obviousness Principles
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`15.
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`I have been advised that a patent claim may be invalid as obvious and
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`unpatentable under § 103 if the differences between the subject matter patented
`
`and the prior art are such that the subject matter as a whole would have been
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`obvious at the time the invention was made to a person having ordinary skill in the
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`art to which the subject matter pertains.
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`16.
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`I have also been advised that several factual inquiries underlie a
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`determination of obviousness. These inquiries include the scope and content of the
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`prior art, the level of ordinary skill in the field of the invention, the differences
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`between the claimed invention and the prior art, and any objective evidence of
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`non-obviousness to the extent it exists.
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`17.
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`I understand that obviousness can be established by combining or modifying
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`the teachings of the prior art to achieve the claimed invention. It is also my
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`understanding that where there is a reason to modify or combine the prior art to
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`achieve the claimed invention, there must also be a reasonable expectation of
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`success for a finding of obviousness.
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`18.
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`I understand that a claimed invention may be obvious if some teaching,
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`suggestion, or motivation that would have led a person of ordinary skill in the art
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`to combine the invalidating references exists. I also understand that this suggestion
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`or motivation may come from such sources as explicit statements in the prior art or
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`from the knowledge of one of ordinary skill in the art. Alternatively, any need or
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`problem known in the field at the time and addressed by the patent may provide a
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`reason for combining elements of the prior art.
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`19.
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`I also understand that the law requires a “common sense” approach of
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`examining whether the claimed invention is obvious to a person of ordinary skill in
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`the art. For example, I understand that combining familiar limitations according to
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`known methods is likely to be obvious when it does no more than yield predictable
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`results. I have been advised that when there is a design need or market pressure
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`and a finite number of predictable solutions, a person of ordinary skill may be
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`motivated to apply his or her skill and common sense in trying to combine the
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`known options in order to solve the problem.
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`20.
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`It is also my understanding that one way to rebut a finding of obviousness is
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`to present evidence of secondary considerations of nonobviousness, such as
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`unexpected results, commercial success, long felt but unsolved need, and the
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`failure of others to achieve the claimed invention. I also understand that, in order to
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`be relevant to the issue of obviousness, such secondary indicia must have some
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`connection (or nexus) to the claimed invention.
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`21.
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`I have followed these principles in my analysis below.
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`VII. Person of Ordinary Skill in the Art
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`22. The ’154 patent claims priority to a U.S. provisional application filed on
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`July 25, 2005. In my opinion, a person of ordinary skill in the art in July 2005
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`would be a person with a graduate degree (MS or PhD) in medical physics or a
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`related field (e.g., Physics or Engineering), and three years of work in radiation
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`oncology beyond the completion of their degree, including at least three years of
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`experience with programming of treatment planning software systems and
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`programming of optimization processes.
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`VIII. Technology Background: Radiation Therapy
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`23. The ’154 patent is not the first reference to disclose treatment plans for
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`rotatable radiation therapy machines, or the general use of iterative optimization
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`for optimizing such treatment plans. As described here in my declaration, radiation
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`treatment plans, along with methods to optimize such treatment plans and the
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`machines to implement them, have long been known in the radiation therapy field.
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`By July 2004, it was well known in the radiation therapy industry to develop and
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`deliver radiation treatment plans by a machine that rotates a radiation source
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`around a patient. The following discussion of the prior art supports this.
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`A. Radiation Treatment Machines
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`24.
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`In radiation therapy, a device such as a linear accelerator (“linac”) generates
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`a source of radiation for the treatment of patients. The radiation source outputs a
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`beam having a controlled amount of radiation. A typical linac includes a gantry to
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`rotate the radiation source, and thus the beam, around a horizontal axis. Because
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`the gantry’s horizontal axis is fixed and the source is fixed to the gantry, the source
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`rotates in a plane around the patient. A patient table (or couch) supports the patient
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`laying down along the horizontal axis. Fig. 1 of Whitham (Ex. 1039) (annotated
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`version reproduced here) shows a typical radiation treatment machine.
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`25. During therapy, a patient is positioned on the couch so that a specified target
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`(e.g., a tumor) to be irradiated coincides with the beam’s isocenter, which is the
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`location where the beam’s central axis intersects the gantry’s rotational axis. As the
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`gantry rotates, the beam output at each angle of rotation irradiates the tumor. A
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`goal of radiation therapy is to irradiate target tissue while minimizing radiation
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`delivered to healthy tissue. See Ex. at 1008 at Abstract; 3:15-17.
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`26. Prior to the therapy, a dosimetrist or other clinician will create a “treatment
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`plan” that defines the set of instructions used by the treatment machine to deliver
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`radiation to the target. One goal of this treatment plan will be to irradiate the
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`cancerous target tissue, while minimizing the amount of radiation delivered to
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`healthy tissue. The treatment plan will thus define the directions (or angles) at
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`which the machine outputs a beam towards the patient, as well as the type of beam
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`(e.g., the shape of the beam) at each direction. See Ex. at 1008 at Abstract; 3:15-17.
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`27. The basic strategy is to use multiple beams of radiation from multiple
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`directions that “cross-fire” at the tumor volume. The dose delivered along the beam
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`axes will be relatively low as compared to the prescribed tumor dose, while the
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`cumulative radiation dose received at the tumor, which often contains the isocenter,
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`will be relatively higher. In this way, the healthy tissue that each beam passes
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`through receives a relatively low level of radiation, while the dose to the tumor
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`cells is higher.
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`28. To protect healthy tissue, a typical treatment plan will shape the beam to
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`conform it to a cross-sectional shape of the target tumor as viewed from the
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`corresponding beam direction, known as a beam’s eye view (“BEV”). The
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`treatment machine uses a multileaf collimator (“MLC”), with two opposing banks
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`of movable “leaves” (also referred to as “veins”), to form an aperture that shapes
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`the cross-section of the beam passing through this aperture. The shape of the beam
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`may be formed so it roughly matches the tumor’s shape or has a shape defined by
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`an optimizer.
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`29. Fig. 1a of Yu ’902 (Ex. 1008) (reproduced below on the left) shows a
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`radiation “field” shaped by leaves 21 of an MLC. Id. at col. 6, lines 28-43. Fig. 4 of
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`Earl Article (Ex. 1009) (reproduced below on the right) shows a sample sequence
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`of MLC aperture shapes. Id. at 1083. In the figure on the right, the darkened area
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`represents the MLC aperture, while the remaining area represents the position of
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`the MLC leaves that block or absorb any impinging portion of the field. The
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`portion of the beam passing through the MLC aperture will thus have a cross-
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`sectional shape defined by the MLC aperture (e.g., the darkened area in the figure
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`at below right). The term “field” is commonly used in this art to refer to the two-
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`dimensional projection of radiation delivered by a beam. The term “subfield” is
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`commonly used in this art when overlapping fields (or beams) are delivered at a
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`beam direction and, thus, each field is referred to as a “subfield.”
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`B. Radiation Treatment Plans
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`30. By 2004, several methods of radiation delivery were widely known. These
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`included Conformal Therapy, Intensity Modulated Radiation Therapy (“IMRT”),
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`and Intensity Modulated Arc Therapy (“IMAT”).
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`31. The Conformal Therapy method, for instance, uses multiple beams, each
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`having a cross-sectional shape that conforms to the cross-sectional shape of the
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`tumor as seen from the BEV of the corresponding beam direction. IMRT and
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`IMAT are more advanced and will be described below.
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`32.
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`In developing a treatment plan, the arrangement of beams is chosen so the
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`dose distribution meets a clinician's prescription. Thus, the main objective of
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`treatment planning is designing a collection of beams (e.g., beams of particular
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`shapes, orientations, and associated doses) to optimize the dose distribution in the
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`patient. A treatment planning system typically uses computers to optimize the dose
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`distribution based on a set of preselected variables. After optimization, the
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`variables defined by the treatment plan, such as gantry beam angles, couch angles,
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`and corresponding MLC aperture shapes, are transferred to the linac’s control
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`system to deliver radiation to the patient.
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`33.
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`I describe below the relevant types of radiation delivery techniques known
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`by July 2004 and the known techniques to optimize the associated treatment plans.
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`1.
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`Intensity-Modulated Radiation Therapy (“IMRT”)
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`34. With IMRT, radiation beams shaped by an MLC are delivered at different
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`angles around the patient. The beam shapes either remain constant during the
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`delivery of radiation or can dynamically change during radiation delivery. That is,
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`the MLC can use a constant shape for each beam at each angle or the MLC can use
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`multiple shapes at each angle (or, said differently, multiple overlapping beams of
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`different shapes at each angle).
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`35. Fig. 17 of Löf (Ex. 1013) (reproduced below) shows examples of beams
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`delivered at different gantry angles as is typical in IMRT. Ex. 1013.
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`The above annotated version of Fig. 17 identifies the different beam angles for
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`scenarios with 3 fixed beams (the top two images). Although not annotated, Fig. 17
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`also shows the different beam angles for scenarios with 5 fixed beams (the middle
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`two images) and for scenarios with 9 fixed beams (the bottom two images). The
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`greater the number of subfields for each beam direction, the more likely it is that
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`the IMRT treatment plan will achieve the clinical goals. For this reason, it is
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`common for more complicated IMRT plans to include multiple subfields at each
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`angular direction.
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`36. Because IMRT allows for an increased number of beams, where each
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`subfield at each direction can have any shape defined by the optimizer, IMRT is an
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`improvement over conventional conformal techniques, which restrict each beam to
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`a single field that conforms to the target tumor’s cross-sectional shape as seen from
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`the BEV of the corresponding beam direction. IMRT thus has the ability to better
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`sculpt the dose distribution around critical structures by allowing for a greater
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`number of possible beam combinations. Consequently, the sparing of critical
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`structures and normal tissue is improved, allowing physicians to escalate the dose
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`to the tumor.
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`37. Several of the prior art references relied upon in Section XI below describe
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`IMRT.
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`a)
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`Earl ’261
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`38. For instance, Earl ’261 (Ex. 1003) discloses that IMRT can be used to
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`deliver “optimized non-uniform radiation beam intensities from each beam angle.”
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`Ex. 1003 at ¶ 10. Earl ’261 further describes that each beam is conceptually
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`divided into a grid of pencil beams or “beamlets.” Id. at ¶ 19. As known in this
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`industry, dividing a beam into beamlets can enable software calculations to
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`determine how each beamlet impacts the overall dose distribution delivered by the
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`actual beam. Earl ’261 thus explains how, by using a conventional dose calculation
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`method, “[t]he dose distribution from each of these pencil beams is calculated.” Id.
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`39. Earl ’261 also addresses the complexity of IMRT treatment plans. “Because
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`of the complexity of the treatment plans for IMRT, an automated system is
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`required” to generate the optimized plan. Id. at ¶ 11. In IMRT, “[w]hen radiation is
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`delivered with fixed beam angles, a series of beam shapes are delivered at each
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`beam angle either dynamically, where the leaves of the MLC move during
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`irradiation, or in a step-and-shoot fashion, where the radiation is paused during the
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`movement of MLC leaves.” Id. at ¶ 12.
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`40. Earl ’261 includes a block-diagram of a radiation delivery machine for
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`implementing an IMRT treatment plan (or, as discussed below, an IMAT plan). Id.
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`at ¶¶ 21, 24, 33; Fig. 4. Specifically, Fig. 4 shows a linac 1 as a source for
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`delivering radiation to a target volume of a patient. Id. at ¶ 25. Radiation exits the
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`source’s treatment head mounted on a rotatable gantry (not illustrated in Fig. 4). Id.
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`The treatment head can include an MLC to shape the radiation field. Id. The gantry
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`can “rotate about a horizontal axis H of rotation around the patient who is lying on
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`the bed.” Id. The linac source then outputs a radiation beam aimed at a target of the
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`patient. Id. at ¶ 25-26. By rotating about the horizontal axis H, the gantry allows
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`for a change in the angle of treatment. Id. at ¶ 26.
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`2.
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`Intensity-Modulated Arc Therapy (“IMAT”)
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`41. As noted above, IMAT was well known by July 2004. In IMAT, radiation is
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`delivered continuously by a source that rotates continuously along one or more
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`arcs around the patient. During delivery, the MLC changes the shape of the
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`radiation beam in an optimized fashion to provide tumor-conformal dose
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`distributions. The beam’s intensity can also change along the arcs.
`
`a)
`
`Yu ’902
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`42. One of the earliest patent publications on IMAT is an Elekta patent to Cedric
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`Yu. Ex. 1008.1 Yu ’902 is recognized as a pioneering patent on IMAT; Cedric Yu
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`was one of the original pioneers of IMAT. See Ex. 1044. Yu ’902 depicts a subject
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`undergoing IMAT. Id. at Fig. 1 (annotated version reproduced here). The apparatus
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`10 includes a rotatable gantry 14, a couch 16, an MLC controller 22, and a linear
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`accelerator 24, where the gantry 14 has a radiation source 18 and an MLC 20. See
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`id. at 6:8-62.
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`1 I understand that during prosecution of the application that became the ’770
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`patent, Yu ’902 was cited. Ex. 1001 at 2.
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`43.
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`IMAT has benefits over IMRT particularly in reduced delivery time. IMAT
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`is also more complex in that the gantry continuously moves as the MLC also varies
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`the shape of the beam in a manner that is not always conformal to the target
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`tumor’s physical dimensions. See id. at 3:20-23. For instance, Yu ’902 explains that
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`IMAT may use multiple arcs around the patient. See id. at Fig. 3 and 10:50-58.
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`Each arc has “subfields” associated with different angular directions along the arc,
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`each of which has a particular shape and a particular intensity. See id. at 7:13-18.
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`Yu ’902 teaches, however, that a complex plan having different intensity levels
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`may be implemented by delivering multiple arcs around the patient. See id. at
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`7:18-26. Each arc is thus associated with one or more subfields.
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`b)
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`Earl Article
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`44. Earl Article improves upon Yu ’902 by providing an optimization system for
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`IMAT treatment plans. In contrast to previous “forward planning” systems (e.g.,
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`that generate radiation delivery parameters based on the particular tumor), Earl
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`Article describes an automated “inverse planning” system that optimizes the
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`delivery parameters based on a desired dose distribution. Earl Article thus
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`proposes an iterative optimization process that “simultaneously optimizes both the
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`field shapes and the arc weights.” Id.; see also id. at 1079. The “field shapes” refer
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`to the shapes of the beam defined by the MLC aperture. See, e.g., id. at 1076
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`(explaining that “the leaves of the MLC change shape as the gantry rotates during
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`delivery”). The “arc weights” (also referred to as “beam weights”) refer to a
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`parameter, such as dose rate, that can change a beam intensity value. See, e.g., id.
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`at 1086 (describing that the system programs the “weights of the beams” to be
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`“independent” and, thus, “different from one another” to allow “the dose rate to
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`change during delivery”). Finally, while Earl Article teaches that dose rate and
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`gantry speed may be varied during delivery of radiation, id. at 1076, 1084-86, Earl
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`Article notes that the particular radiation therapy machine will impose “delivery
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`constraints” on the optimization process, id. at 1079; see also id. at 1080 (noting
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`that the linac used in the underlying study was limited in that it required a
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`“constant dose rate and a constant gantry rotation speed.”)
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`c)
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`Earl ’261
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`45. Like Yu ’902 and Earl Article, the system described in Earl ’261 specifies
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`evenly-spaced discrete angles or the number and range of each arc at which
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`parameters are calculated. Ex. 1003 at ¶¶ 25, 36-37. Then, the treatment planning
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`system “automatically calculates evenly spaced radiation beams to approximate the
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`range of rotation of the gantry.” Id. at ¶ 37. The different beam angles, beam
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`energies, and the number and range of arcs, each constitute a set of one or more
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`radiation delivery parameters associated with various points along the trajectory of
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`the radiation source. Other radiation delivery parameters include “the positions of
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`the MLC leaves used to shape each aperture for each beam angle, and the relative
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`weight (intensity) of each aperture shape assigned to each aperture.” Ex. 1003 at
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`¶ 41. Each of these parameters is associated with a point along the trajectory, and
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`thus they make up the claimed “control points.”2 Given these parameters, Earl ’261
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`also notes the complexity of IMAT. See, e.g., Ex. 1003 at ¶ 15 (explaining that due
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`2 The term “control point” has become the standardized term in the radiation
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`therapy field to refer to the set of radiation delivery parameters used to control a
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`therapy machine during radiation delivery. The DICOM standard from 1997, for
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`example, explains that applicable treatment parameters are specified at a given
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`control point (“Control Point 0”). Ex. 1048 at 80.
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`to maximum speed of MLC leaves, constraints are placed on differences in
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`aperture shapes between adjacent beam gantry angles). Earl ’261 thus discloses an
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`inverse-planning method for IMAT treatment planning, as discussed more below.
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`d) Duthoy
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`46. While Duthoy (Ex. 1005) details a particular type of clinical treatment using
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`IMAT, it describes a strategy for optimizing an IMAT plan over several steps,
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`including “weight optimization of machine states, leaf position optimization
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`adapted to meet the maximal leaf speed constraint, and planner-interactive
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`optimization of the start and stop angles.” Id. at 1019. The system then calculates
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`and delivers a sequence of “control points” associated with various parameters to
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`control the therapy machine as the gantry rotates along an arc. Id. at 1022. Duthoy
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`thus addresses complexities recognized in, e.g., Earl ’261. And in doing so, the
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`strategy employed by Duthoy transforms optimized “virtual arcs” into deliverable
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`arcs. Id. at 1022. The resultant IMAT strategy was found to be “deliverable in an
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`acceptable time slot and to produce dose distributions that are more homogeneous
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`than those obtained with a [conventional] plan.” Id. Thus, Duthoy provides an
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`example of the implementation and progression of IMAT from its inception by
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`Cedric Yu.
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`3. Optimization of Treatment Plans
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`47. The complexity of radiation treatment planning, including IMRT and IMAT,
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`is such that generating treatment plans via manual trial-and-error is undesirable in
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`a clinical environment due to inefficiency. Instead, automated software systems
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`optimize these plans through “inverse-planning” optimization techniques. These
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`optimization techniques first define a desired output (e.g., an optimal dose
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`distribution in the patient) and then optimize the combination of input parameters
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`(e.g., the parameters that c