Prosecution Insights
Last updated: April 19, 2026
Application No. 18/836,161

METHOD FOR DETERMINING RELATIVE DETECTOR ELEMENT EFFICIENCIES IN A PET-SCANNING DEVICE

Non-Final OA §103
Filed
Aug 06, 2024
Examiner
MALEVIC, DJURA
Art Unit
2884
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Positrigo AG
OA Round
1 (Non-Final)
78%
Grant Probability
Favorable
1-2
OA Rounds
2y 10m
To Grant
88%
With Interview

Examiner Intelligence

Grants 78% — above average
78%
Career Allow Rate
640 granted / 819 resolved
+10.1% vs TC avg
Moderate +10% lift
Without
With
+10.3%
Interview Lift
resolved cases with interview
Typical timeline
2y 10m
Avg Prosecution
38 currently pending
Career history
857
Total Applications
across all art units

Statute-Specific Performance

§101
1.5%
-38.5% vs TC avg
§103
65.5%
+25.5% vs TC avg
§102
22.3%
-17.7% vs TC avg
§112
8.0%
-32.0% vs TC avg
Black line = Tech Center average estimate • Based on career data from 819 resolved cases

Office Action

§103
Notice of Pre-AIA or AIA Status The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . Information Disclosure Statement The information disclosure statement (IDS) submitted on 08/06/2024 was considered by the examiner. The PCT international search report filed 08/06/2024 and the PCT written opinion of the international searching authority were considered by the examiner. Claim Rejections - 35 USC § 103 The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action: A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made. Claim(s) 1 – 7 and 10 – 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang et al. (US Patent 7,718,954 B2) in view of Laurence et al. (US Pub. No. 2017/0371046 A1) and Bazrafan (US Pub. No. 2017/0032170 A1). With regards to claims 1 and 10, Wang discloses a method and apparatus (i.e., a small or a large PET scanner) for calibrating a PET scanner 100 (Figures 1 – 6B) (Col. 9, Lines 40 – 67) (Col. 10, Lines 1 – 36) (Abstract). Wang teaches acquiring LOR sinogram data. Each sinogram bin within a phantom region comprises multiple counts and crystal efficiency normalization is performed see equations 2, 8, 11, 12 and 14 (Col. 9, Line 40 – Col. 10, Lie 41). Notice that, in essence, the sinogram is the primary, organized form of raw PET data, acting as a collection of projection "histograms" that map the object's activity from many angles. Wang also teaches a singles detection capturing individual photon detection, providing essential data to filter out errors and accurately reconstruct the true annihilation events that form the PET image (Col. 10, Lines 38 – 41). Wang’s key teachings are directed to component method and system for PET detector efficiency normalization wherein determining crystal (detector-element) efficiencies for scan data; sinogram/histogram generations; phantom-based normalizing. Wang implements an iterative smoothing of crystal-efficiency normalization factors and panel detector PET geometry, see equations 1 - 16 (Figures 1 and 2). Lastly, Wang teaches improving noise in order to provide enhanced efficiency (Col. 6, Lines 63++). Wang fails to expressly disclose “singles” as in non-coincidence histogram binned with corresponding detector elements reflecting a sum detected during certain period of time and applying a spatial high pass filter to said singles data. Laurence discloses a positron emission tomography (PET) imaging system 10 (Figure 2). Radiation events are detected by the PET detector rings 20 via scintillator and silicon photomultipliers (SiPMs) or other detectors such as photomultiplier tubes (PMT's), or avalanche photodiodes (APDs) or the like making up detector arrays of the PET rings 20. A calibration processor 24 performs the SUV calibration including per-pixel dead time correction to generate an SUV calibration including dead time 26 [0021] Laurence further teaches single events detected at detector pixel/element level (i.e., list mode singles events) [0042]. Histograms are mapped and where pixel intensity corresponds to singles rate for a detector pixel, while summing of individual singles rates corresponds to a system singles rate, as in, per-element aggregation concept [0043] – [0047]. Notice that Laurence teaches that it is known that both singles and random events have a local spatial variance across the pixel pairs [0035] – [0037], [0041] – [0045]. Bazrafkan relates to imaging process apparatus and methods. Specifically, operating on the same type of data structure (i.e., a spatial map). Notice how FIG. 4 shows images after they have been high pass filtered with a Gaussian high-pass filter [0040] - [0042]. In view of the utility, to suppress spatial bias and emphasize localized detector elements in order to improve the detection of the device, it would have been obvious to a person of ordinary skill in the art at the time the invention was made to modify Wang to include the teachings such as that taught by Laurence and Bazrafkan. With regards to claim 2, Wang discloses a the high-pass filtered histogram data are used for calibration of the PET-scanning device and/or for correction of PET-data acquired by the PET-scanning device (Col. 9, Lines 49 – 64). Notice how the detector efficiency calibration/normalization workflow (See the steps 1 – 4, too). With regards to claim 3, Wang discloses the claimed invention according to claim 1 but fails to expressly disclose a step of norming the histogram data to the sum or average of the singles emissions detected by all detector elements. Laurence teaches to sum the individual single rates to the system singles rate [0043]. Bazrafkan teaches high pass filtering and then to normalized to produced a weighted image as needed [0041] – [0043]. In view of the utility, to reduces noise/artifacts and enhance clarity, it would have been obvious to a person of ordinary skill in the art at the time the invention was made to modify Wang to include the teachings such as that taught by Laurence and Bazrafkan. With regards to claim 4, Wang modified discloses a detector element is formed by a single crystal 107 of the detector 106 of the PET- scanning device 100 (Figure 1) (Col. 9, Lines 49 – 64). With regards to claim 5, Wang modified discloses a histogram data are acquired from a human or animal patient (see the small and large scanners discussed for animals and humans (Col. 9, Lines 40 to Col. 10, Line 42). With regards to claim 6, Wang modified discloses wherein the histogram data are acquired from a phantom (See steps 1 – 4) (Col. 9, Lines 49 – 64). With regards to claim 7, Wang modified discloses an outer surface of the phantom substantially deviates from the inner surface of the detector of the PET-scanning device with respect to its dimensions and/or shape (i.e., scan acquisition of a cylindrical phantom) (Figure 6a – 6b discussion). Notice how FIG. 6 provides an illustration of the differences in solid angle for cylindrical and planar phantoms (Col. 9, Lines 10 – Col. 10, Line 42). With regards to claim 11, Wang discloses a PET-scanning device such as that claimed in claim 1 and a computer and/or processor 130 to carry out corrections, imaging data generation, any techniques or instructions as needed and the like (Col. 4, Lines 7 ++) Laurence discloses subject imaging, wherein the processing performed by the calibration processor 24 to generate the SUV calibration 26 is described. This calibration processing leverages the coincidence-based data processing machinery 34, 36 used during imaging. With continuing reference to FIG. 2, the calibration processor 24 determines the relationship of a singles rate to radioactivity of the radiopharmaceutical through direct measurement of the singles rate during the SUV calibration. With reference to FIG. 6, the calibration processor solves the nonlinear system of equations by generating a 2D histogram 600, 602, 604 of the random events. The histogram 600, 602, 604 is a map of the singles rate with a scaling factor [0042] [0043]. Bazrafkan teaches a to image capture and arranged to combine component images corresponding to the succession of images by selecting a median value for corresponding pixel locations of the component images as a pixel value for the combined image (Abstract). At the time the invention was made, it would have been an obvious matter of design choice to a person of ordinary skill in the art to use any of the processors and modify any of the processors taught by Wang, Laurence and Bazrafkan to include instructions to perform the method of claim 1 as needed. With regards to claim 12, Wang discloses the claimed invention according to claim 1 and a computer program for controlling a PET-scanning (Col. 10, Lines 42 – 62). Notice how the method is embodied in a computer program stored in suitable memory storage device 140 and made available to the system 100 and reconstructor 129 (Col. 10, Lines 42 – 62). Claim(s) 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang et al. (US Patent 7,718,954 B2), Laurence et al. (US Pub. No. 2017/0371046 A1) and Bazrafan (US Pub. No. 2017/0032170 A1) in view of Panin (US Pub. No. 2015/0297168 A1). With regards to claim 8, Wang modified discloses a detector of the PET-scanning device according to claim 1 but fails to expressly disclose that the device has a non-circular inner surface. Panin relates to patient-based detector crystal quality control for time-of-flight data acquisition in positron emission tomography systems [0002]. Panin further teaches that PET systems may be used with a particle therapy system and may deviate from the conventional ring form. For example, an in-beam PET system may include only two opposed detectors. The additional opening between the two detectors, for example, may be used to position the patient, or irradiate the patient with a beam passing through this opening without the beam striking the detectors [0006]. In view of the utility, to enable additional capabilities as needed in the therapy arts, it would have been obvious to a person of ordinary skill in the art at the time the invention was made to modify Wang to include the teachings such as that taught by Panin. Claim(s) 9, 13 and 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Wang et al. (US Patent 7,718,954 B2), Laurence et al. (US Pub. No. 2017/0371046 A1) and Bazrafan (US Pub. No. 2017/0032170 A1) in view of Chen et al. (US Pub. No. 2009/0074152 A1). With regards to claims 9, 13 and 14, Wang modified discloses the claimed invention according to claim 1, but fails to expressly disclose a period of time during which the histogram data are acquired is less than 60s, 30s, and/or 10s. Notice that Laurence already uses timing or periods as time periods are used in histograms [0043] (Figure 6). Chen discloses a method for determining quality of sinograms produced by a medical imaging device (Abstract). Chen further discloses how acquisition time can be shorten as needed and treats scan time as a managed parameter with motivation to have shorter scan times [0061] – [0065]. Notice that where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. In view of the utility, to enable additional capabilities such as quality check procedure should make efficient, increase scanner throughput, and potentially lower radiation dose or tracer amount, it would have been obvious to a person of ordinary skill in the art at the time the invention was made to modify Wang to include the teachings such as that taught by Chen. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to DJURA MALEVIC whose telephone number is (571)272-5975. The examiner can normally be reached M-F (9-5). Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Dave Porta can be reached at (571) 272-2444. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /DJURA MALEVIC/Examiner, Art Unit 2884 /UZMA ALAM/Supervisory Patent Examiner, Art Unit 2884
Read full office action

Prosecution Timeline

Aug 06, 2024
Application Filed
Jan 21, 2026
Non-Final Rejection — §103 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12589258
COMPUTER-IMPLEMENTED MEDICAL METHOD OF IRRADIATION (RT) TREATMENT PLANNING
2y 5m to grant Granted Mar 31, 2026
Patent 12571729
APPARATUS FOR TRANSMITTING AND/OR RECEIVING TERAHERTZ RADIATION, AND CONTROL DEVICE THEREFOR
2y 5m to grant Granted Mar 10, 2026
Patent 12553770
METHOD AND APPARATUS CONFIGURED TO COUNT N-PHOTON EVENTS
2y 5m to grant Granted Feb 17, 2026
Patent 12553824
MONITORING CONDITIONS AND HEALTH OF ARTISTIC WORKS
2y 5m to grant Granted Feb 17, 2026
Patent 12553830
FLUORESCENT INK AND IMAGING SYSTEM FOR DEFECT DETECTION ON PRINTED PHOTOSENSITIVE OBJECTS
2y 5m to grant Granted Feb 17, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

AI Strategy Recommendation

Get an AI-powered prosecution strategy using examiner precedents, rejection analysis, and claim mapping.
Powered by AI — typically takes 5-10 seconds

Prosecution Projections

1-2
Expected OA Rounds
78%
Grant Probability
88%
With Interview (+10.3%)
2y 10m
Median Time to Grant
Low
PTA Risk
Based on 819 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month