US 11369322

US patent 11369322, titled "Methods and systems for retrospective internal gating," was issued on June 28, 2022, from an application filed on December 14, 2020. The patent is currently assigned to Memorial Sloan Kettering Cancer Center, and the inventor is Adam L. Kesner.

Abstract:
The patent describes a method for reconstructing respiratory-gated PET (Positron Emission Tomography) images directly from raw PET data. It achieves this by using motion information derived from the signal fluctuations within individual voxels (3D pixels) of the image data to create respiratory phase information. This approach enables the reconstruction of respiratory-gated PET images without the need for external hardware and in a fully automated manner.

Plain-language overview of independent claims:

• Claim 1 (Method for retrospective internal gating): This claim describes a multi-step method. First, image data is acquired over different time points (t1...tn) to create images of a moving object. Second, information from multiple "arrays" (which can be understood as voxels or regions of interest) within this image data is extracted. Third, this extracted information is used to generate a "time varying object motion function," essentially a profile of how the object is moving over time. Fourth, based on this motion function, the specific phase of the object's motion is determined (e.g., a particular point in a breathing cycle). Finally, an image is generated that corrects for the object's motion using this determined phase information and the original acquired image data.
• Claim 19 (Non-transitory computer-readable medium): This claim covers a computer-readable storage medium (like a hard drive or flash drive) that contains a program. When this program is run by one or more processors, it performs the exact same steps as described in Claim 1: acquiring image data, extracting array information, generating a time varying object motion function, determining motion phase information, and generating a motion-corrected image.
• Claim 20 (System): This claim describes a system comprising one or more processors and a non-transitory computer-readable medium. This medium stores instructions that, when executed by the processors, cause the system to perform the same method steps outlined in Claim 1: acquiring image data, extracting array information, generating a time varying object motion function, determining motion phase information, and generating a motion-corrected image.

A search for "CAFC 2026 dockets US11369322B2" did not yield any specific results indicating ongoing cases involving US11369322 in the U.S. Court of Appeals for the Federal Circuit for the year 2026.

As of April 26, 2026, there is no known litigation involving US patent 11369322. Searches on Unified Patents Portal for "Litigation Case List" and "PTAB Case List" did not return any results for US11369322.

Proceedings overview

There are no AIA trial proceedings (Inter Partes Review, Post-Grant Review, or Covered Business Method) on file for US patent 11369322. The USPTO ODP API reports no proceedings as of its most recent ingest, and a web search did not surface any additional or recently-filed proceedings. This means the patent has not been challenged at the PTAB, offering no specific defensive posture from prior PTAB outcomes for a potential defendant.

Strategic summary

As of the current date (2026-06-02), all 20 claims of US11369322 remain untested and are considered sustained by the PTAB simply due to the absence of any challenges. No claims have been canceled or invalidated through an AIA trial proceeding.

Estoppel landscape: Since no AIA trial proceedings have been instituted or concluded, there is no estoppel under 35 U.S.C. § 315(e)(2) for any petitioner or their privies concerning US11369322. All prior art grounds (e.g., § 102 or § 103 challenges) remain available for potential future IPR or PGR petitions.

Pattern signals: The absence of PTAB activity suggests that this patent, despite being granted in 2022 and having a priority date stretching back to 2007, has not yet been asserted in a way that would provoke an AIA trial, or potential infringers have not yet deemed it worthwhile to challenge at the PTAB. There is no pattern of aggressive PTAB appeals by the patent owner or involvement of defensive aggregators.

Recommended next steps

Given the absence of any PTAB activity, a potential defendant should be aware that the claims of US11369322 have not been judicially vetted for patentability against prior art in an IPR or PGR.

If facing an assertion of this patent:

• Prior Art Search: Conduct a thorough prior art search to identify potential invalidity grounds under 35 U.S.C. § 102 and § 103, as these grounds remain entirely open for a future PTAB petition.
• Claim Analysis: Perform a detailed claim construction and infringement analysis for all asserted claims.
• Evaluation of PTAB Challenge: Consider whether filing an IPR or PGR petition would be a viable strategy, particularly if strong prior art can be identified. The absence of previous challenges means that a petitioner would not be estopped from raising any grounds.

Inventors

• Adam L. Kesner (Memorial Sloan Kettering Cancer Center at the time of filing)

Original assignee

The original assignee named on the issued patent is Memorial Sloan Kettering Cancer Center. They are a prominent cancer treatment and research institution, and their primary line of business is healthcare and medical research. Given the nature of their work, it is highly probable they utilize or embody the claimed methods and systems in their clinical and research activities. Memorial Sloan Kettering Cancer Center is currently operating.

Assignment timeline

• 2017-05-30 (executed) / recorded 2024-05-30 — Reel 067574/0953
  • Conveyance: Assignment
  • Assignor: Kesner, Adam
  • Assignee: Memorial Sloan Kettering Cancer Center
  • Correspondent: Not specified on this record.
  • Context: Internal transfer of inventor's interest to the employer.

Timeline diagram

timeline
    title Ownership of US 11369322
    2007 : Priority date
    2020 : Application filed
    2022 : Issued to Memorial Sloan Kettering Cancer Center
    2024 : Assignment of inventor interest

NPE / troll-pattern signals

1. Shell-entity transfer — not present. The sole recorded assignment is from the inventor to a major non-profit research institution.
2. Known asserter in the chain — not present. Memorial Sloan Kettering Cancer Center is not a known patent asserter.
3. Repeat correspondent across the chain — unclear. The correspondent information was not specified in the single recorded assignment, making it impossible to assess recurrence.
4. Cascading transfers — not present. Only one assignment is recorded.
5. Pre-litigation transfer — not present. There is no indication of litigation immediately following the recorded assignment.
6. Bankruptcy fire-sale — not present. Memorial Sloan Kettering Cancer Center is an active, operating institution.
7. Privateering — not present. There is no evidence of an operating company transferring the patent to an NPE for assertion.
8. Defensive aggregator (anti-NPE) — not present. The patent is held by Memorial Sloan Kettering Cancer Center, not a defensive aggregator.

Verdict

Insufficient data. Only one assignment is recorded (from the inventor to the original assignee), and there is no information available regarding a correspondent for this transaction. While Memorial Sloan Kettering Cancer Center is clearly an operating entity, without further assignment records, it's impossible to determine if the patent has been transferred to a licensing-only entity or a known asserter.

The USPTO website provides tools for patent searches, including Patent Public Search which allows searching by keywords, inventor, or publication number.

Here's an analysis of the prior art cited in US patent 11369322, focusing on potential anticipation under 35 U.S.C. § 102. Please note that a full anticipation analysis would require a detailed claim-by-claim comparison and expert legal opinion. The descriptions below highlight aspects that could potentially anticipate elements of the independent claims (1, 19, and 20).

Most Relevant Prior Art for US11369322:

The independent claims of US11369322 generally describe a method, computer-readable medium, and system for retrospective internal gating by:

1. Acquiring image data over time (t1...tn) from a moving object.
2. Extracting information from arrays (e.g., voxels) within this data.
3. Generating a time-varying object motion function from this extracted information.
4. Determining motion phase information from the motion function.
5. Generating a motion-corrected image using the phase information and acquired data.

The most relevant prior art would demonstrate these core steps, particularly the internal, software-based derivation of motion from image data itself for gating, as opposed to external hardware.

Here's a breakdown of the cited patents that appear most relevant to the core concepts of US11369322:

• US7359535B2 (Systems and methods for retrospective internal gating)

  • Full Citation: US7359535B2, "Systems and methods for retrospective internal gating", filed June 20, 2003, issued April 15, 2008.
  • Brief Description: This patent describes methods and systems for retrospective internal gating using time-varying data from an imaging system. It involves acquiring time-varying image data, deriving an internal gating signal from this data (e.g., from individual voxels or regions of interest), and then using this signal to sort or reconstruct images to reduce motion artifacts. The description explicitly mentions generating a "gating function" based on time-activity curves of voxels.
  • Potential Anticipation (35 U.S.C. § 102): This patent appears highly relevant as it describes "retrospective internal gating" and explicitly mentions deriving a gating signal from "time-activity information of individual voxels" to create a "gating function," which aligns closely with the "time varying object motion function" and "phase information" in claims 1, 19, and 20 of US11369322. The concept of using internal image data for gating, rather than external hardware, is central to both.

• US20050123183A1 (Data driven motion correction for nuclear imaging)

  • Full Citation: US20050123183A1, "Data driven motion correction for nuclear imaging", filed September 2, 2003, published June 9, 2005.
  • Brief Description: This application details a method for motion correction in nuclear imaging (like PET) where motion information is extracted directly from the acquired emission data. It describes identifying pixels (or voxels) that exhibit cyclical variations corresponding to physiological motion (e.g., respiration) and using these variations to derive a motion curve for gating.
  • Potential Anticipation (35 U.S.C. § 102): This application is highly relevant as it focuses on "data driven motion correction" in nuclear imaging by extracting cyclical motion signals from individual pixels/voxels to create a motion curve for gating. This directly addresses the acquisition of image data, extraction of information from arrays, generation of a motion function, and subsequent image correction, as described in claims 1, 19, and 20 of US11369322.

• US7574249B2 (Device-less gating of physiological movement for improved image detection)

  • Full Citation: US7574249B2, "Device-less gating of physiological movement for improved image detection", filed February 8, 2005, issued August 11, 2009.
  • Brief Description: This patent discloses a method and system for generating a physiological movement gating signal without external devices. It involves acquiring medical image data over time, identifying areas in the data that exhibit physiological motion, generating a motion curve from these areas, and using the motion curve to gate the image data.
  • Potential Anticipation (35 U.S.C. § 102): The emphasis on "device-less gating" and deriving a "motion curve" directly from medical image data to correct for physiological movement (like respiration) aligns very closely with the claimed invention of US11369322 (claims 1, 19, and 20).

• US20080253636A1 (Respiratory motion extraction from tomographic projection and image data)

  • Full Citation: US20080253636A1, "Respiratory motion extraction from tomographic projection and image data", filed April 11, 2007, published October 16, 2008.
  • Brief Description: This application describes techniques for extracting respiratory motion from tomographic projection data or reconstructed image data. It includes analyzing changes in image features or signal intensities over time to derive a respiratory motion signal, which can then be used for gating or motion correction.
  • Potential Anticipation (35 U.S.C. § 102): This reference explicitly addresses "respiratory motion extraction" from image data, which is a key component of generating the "time varying object motion function" and "phase information" in US11369322 (claims 1, 19, and 20). The focus on internal data for motion detection makes it highly relevant.

Other relevant citations, but potentially less direct anticipation of the core "internal gating" aspect:

While the patents below also address motion correction or gating, they may differ in their specific approach to deriving the motion information internally from image data in the same manner as US11369322, or they might focus on different aspects of imaging or correction.

• US6144874A (Respiratory gating method for MR imaging)

  • Full Citation: US6144874A, "Respiratory gating method for MR imaging", filed October 15, 1998, issued November 7, 2000.
  • Brief Description: This patent describes a method for respiratory gating in MRI using a navigator echo to detect respiratory motion.
  • Potential Anticipation (35 U.S.C. § 102): This discusses respiratory gating, but the method for detecting motion (navigator echo) is different from the voxel-based signal fluctuation analysis of US11369322.

• US6298260B1 (Respiration responsive gating means and apparatus and methods using the same)

  • Full Citation: US6298260B1, "Respiration responsive gating means and apparatus and methods using the same", filed February 25, 1998, issued October 2, 2001.
  • Brief Description: This patent describes an apparatus for respiration-responsive gating using a sensor that detects movement of the chest or abdomen.
  • Potential Anticipation (35 U.S.C. § 102): This relies on an external sensor for gating, which is explicitly contrasted by the internal, software-derived gating of US11369322.

• US6501981B1 (Apparatus and method for compensating for respiratory and patient motions during treatment)

  • Full Citation: US6501981B1, "Apparatus and method for compensating for respiratory and patient motions during treatment", filed March 16, 1999, issued December 31, 2002.
  • Brief Description: This patent focuses on compensating for motion during radiation treatment, often involving tracking markers or external respiratory monitors.
  • Potential Anticipation (35 U.S.C. § 102): Similar to US6298260B1, this patent appears to rely on external means for motion compensation rather than the internal data-driven approach of US11369322.

• US6539074B1 (Reconstruction of multislice tomographic images from four-dimensional data)

  • Full Citation: US6539074B1, "Reconstruction of multislice tomographic images from four-dimensional data", filed August 25, 2000, issued March 25, 2003.
  • Brief Description: This patent describes methods for reconstructing 4D (3D + time) tomographic images, which inherently deal with time-varying data but may not specifically detail the derivation of a motion function from voxel fluctuations for gating in the same way.
  • Potential Anticipation (35 U.S.C. § 102): While dealing with 4D data, the specific mechanism for deriving the "time varying object motion function" from internal image data for gating as claimed in US11369322 might not be fully present.

• US7756307B2 (Method of, and software for, conducting motion correction for a tomographic scanner)

  • Full Citation: US7756307B2, "Method of, and software for, conducting motion correction for a tomographic scanner", filed October 17, 2003, issued July 13, 2010.
  • Brief Description: This patent describes software-based motion correction for tomographic scanners, which is broad and could encompass various techniques.
  • Potential Anticipation (35 U.S.C. § 102): The broad nature of "software for motion correction" means a detailed comparison would be needed to see if the specific steps of deriving the motion function from individual array fluctuations for retrospective gating are disclosed.

This analysis provides an initial assessment of the most relevant prior art. A definitive statement on anticipation would require a more in-depth legal analysis.

Obviousness Analysis of US11369322 under 35 U.S.C. § 103

The patent US11369322, titled "Methods and systems for retrospective internal gating," claims a method, a computer-readable medium, and a system for correcting for motion in acquired image data. The effective prior art date for US11369322 is May 4, 2007, based on its priority claim to U.S. Provisional Patent Application 60/916,200, filed on that date.

The independent claims (Claims 1, 19, and 20) essentially describe a process involving:

1. Acquiring image data over time (t1...tn) for a moving object.
2. Extracting information from multiple arrays (e.g., voxels) derived from this image data.
3. Generating a time-varying object motion function based on this extracted information.
4. Determining phase information for the object's motion from the motion function.
5. Generating a motion-corrected image using the phase information and acquired data.

The core of the invention lies in using "retrospective internal gating" where motion information is derived from "individual voxel signal fluctuations" within the image data itself, rather than external hardware.

A person having ordinary skill in the art (PHOSITA) in medical imaging, as of May 4, 2007, would have been motivated to combine existing prior art references to arrive at the claimed invention, particularly given the known advantages of software-derived, image-based motion correction. The patent itself highlights that "Acquiring and using software derived respiratory signals have several advantages over hardware based methods. The algorithms are image based, and thus machine independent, and can be used with existing scans, or scanners."

For an obviousness analysis, the following prior art references, cited by US11369322 and having priority dates before May 4, 2007, are particularly relevant:

• US7359535B2 (Priority: 2003-06-20, Publication: 2008-04-15) titled "Systems and methods for retrospective internal gating."
• US20050123183A1 (Priority: 2003-09-02, Publication: 2005-06-09) titled "Data driven motion correction for nuclear imaging."
• US20080253636A1 (Priority: 2007-04-11, Publication: 2008-10-16) titled "Respiratory motion extraction from tomographic projection and image data."

Obviousness Argument for Claim 1

1. Acquiring image data corresponding to times t1...tn to be used to generate one or more images corresponding to a moving object:
This step is fundamental to virtually all medical imaging techniques, including CT, PET, and MRI, as acknowledged by the patent itself. Prior art such as US7359535B2 ("Systems and methods for retrospective internal gating"), US20050123183A1 ("Data driven motion correction for nuclear imaging"), US6144874A ("Respiratory gating method for MR imaging"), and US6298260B1 ("Respiration responsive gating means and apparatus and methods using the same") all inherently teach the acquisition of image data for a moving object for subsequent processing or correction.

2. Extracting information for a plurality of arrays derived from the image data:
The patent describes "arrays" as individual voxels or regions of interest within the image data, with "information" being their time-activity values. A PHOSITA, seeking to perform "data driven motion correction" as taught by US20050123183A1, would naturally look to the raw image data itself (e.g., pixel or voxel values) as the source of this "data." Furthermore, US20080253636A1 explicitly teaches "Respiratory motion extraction from tomographic projection and image data," directly supporting the concept of extracting motion-related information from the acquired image data.

3. Generating a time varying object motion function based on the extracted information for the plurality of arrays of the image data:
The concept of generating a function that characterizes motion from internal data was known. US20050123183A1, with its "Data driven motion correction," strongly implies deriving such a motion function directly from the acquired image data. US20080253636A1 further specifies "Respiratory motion extraction from tomographic projection and image data," which is precisely the generation of a time-varying function of respiratory motion from image data elements (arrays/voxels). The patent itself mentions that "software based methods have been proposed which utilize characterization of structural movement to gate the scans."

4. Determining, based on the time varying object motion function, phase information for motion of the moving object:
Once a time-varying object motion function is generated, determining phase information (e.g., identifying peaks and troughs corresponding to different phases of a respiratory cycle) is a standard practice in medical imaging, particularly for gating applications. Patents like US7359535B2 ("retrospective internal gating"), US6144874A ("Respiratory gating method for MR imaging"), and US6298260B1 ("Respiration responsive gating means and apparatus and methods using the same") would all require and teach the determination of motion phase information for their gating functionalities.

5. Generating at least one image correcting for the motion of the moving object based on the determined phase information for motion of the moving object and the acquired image data:
The ultimate goal of gating is to produce motion-corrected images. The patent explains that "Respiratory gating in is an approach to lessen the image degradation from respiratory motion by separating the breathing cycle into different phases and generating images from data corresponding to each of these phases." Therefore, using the determined phase information to reconstruct motion-corrected images is a direct and obvious consequence of any gating process, as taught by US7359535B2 and other gating references.

Motivation to Combine

A PHOSITA would be motivated to combine the teachings of US7359535B2, US20050123183A1, and US20080253636A1 to arrive at the invention of US11369322 for the following reasons:

1. Addressing a Known Problem: Patient motion during image acquisition was a widely recognized problem causing image degradation and blurring. Respiratory gating was a known solution.
2. Desire for Software-Based Solutions: The advantages of "software derived respiratory signals" over hardware-based methods (machine independence, use with existing scans, automation, temporal alignment) were well-understood and desired in the art.
3. Combination of Retrospective Internal Gating with Data-Driven Extraction:
   • US7359535B2 explicitly teaches "retrospective internal gating," providing the overarching goal of deriving motion information internally from the patient (without external sensors) and applying it retrospectively.
   • US20050123183A1 teaches "data driven motion correction" in nuclear imaging, suggesting that motion information should be extracted directly from the acquired image data itself.
   • US20080253636A1 provides a specific method for "Respiratory motion extraction from tomographic projection and image data," demonstrating how to derive the specific type of motion (respiratory) from the source data (tomographic projection/image data).

A PHOSITA seeking to implement the "internal" aspect of "retrospective internal gating" (US7359535B2) in a software-based manner would naturally look to "data driven" methods (US20050123183A1) that extract motion information directly from image data (US20080253636A1). It would be obvious to use the fluctuations of individual voxel signals (arrays) within the image data as the source for this "data driven" respiratory motion extraction to generate the time-varying object motion function required for retrospective gating. The subsequent steps of determining phase information and generating a corrected image are inherent to any gating process once the motion function is established.

Therefore, the combination of these prior art references would render Claim 1, and by extension the functionally identical Claims 19 and 20, obvious to a PHOSITA as of the priority date of US11369322.