# US 11,026,650 B2 · Methods, systems, apparatuses, and computer program products for automatically determining exposure time for an intraoral image > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,026,650 B2 - Document ID: US11026650B2 - Status: Granted - Kind: B2 - Application number: 16/239,570 - Filed: 2019-01-04 - Published: 2019-07-11 - Granted: 2021-06-08 - Earliest claimed: 2018-01-10 - Assignees: DENTSPLY SIRONA Inc. - Applicants: DENTSPLY SIRONA Inc. - Inventors: Frederick W. Duewer - Web page: https://patentgrep.com/patent/US11026650B2 ## CPC - A61B 6/542: {involving control of exposure} - A61B 6/025: {Tomosynthesis} - A61B 6/467: {characterised by special input means} - A61B 6/488: {involving pre-scan acquisition} - A61B 6/512: {Intraoral means} - A61B 6/5211: {involving processing of medical diagnostic data} - A61B 6/5235: {combining images from the same or different ionising radiation imaging techniques, e.g. PET and CT} - A61B 6/5258: {involving detection or reduction of artifacts or noise} - A61B 6/545: {involving automatic set-up of acquisition parameters} - G16H 50/20: for computer-aided diagnosis, e.g. based on medical expert systems - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - G16H: HEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA ## Abstract A method, apparatus, system, and computer program product for automatically determining exposure time for an intraoral image. The method includes acquiring a low dose pilot projection image of an object to be imaged, performing a sanity check to ensure that a usable exposure is attainable, estimating a remaining exposure time required for an additional projection image, taking the additional projection image and adding the two images together to generate a final image wherein the dose delivered to the x-ray detector is influenced by patient specific dental anatomy. ## Claims ### Claim 1 A method for automatically determining a required exposure time for an intraoral x-ray projection image, the method comprising: acquiring a low dose pilot projection image of an object to be imaged; performing a sanity check to ensure that a usable exposure is attainable; estimating a remaining required exposure time for obtaining one or more additional projection images, the estimating including determining that one or more final images will not be saturated by computing an estimated saturation exposure time required for saturation of an x-ray detector, and comparing said estimated saturation exposure time required for saturation with at least one of an estimated optimal exposure time and a maximum possible exposure time and responsive to determining that the one or more final images will not be saturated, obtaining the one or more additional projection images for one or more final images using the estimated remaining required exposure time such that a dose delivered to the x-ray detector is influenced by patient specific dental anatomy. ### Claim 2 (depends on 1) The method according to claim 1, wherein the obtaining includes performing x-ray imaging and wherein the pilot projection image and one additional projection image are combined to form one final image. ### Claim 3 (depends on 1) The method according to claim 1, wherein the obtaining includes performing tomosynthesis x-ray imaging, wherein the one or more additional projection images are final images and wherein the final images are reconstructed into tomographic images, and wherein the tomographic images are tomosynthesis images. ### Claim 4 (depends on 1) The method according to claim 1, wherein the acquiring includes performing a setup comprising selecting an expectation of an image quality wherein the image quality is discrete or according to a sliding scale. ### Claim 5 (depends on 1) The method according to claim 1, further comprising processing the pilot projection image and the one or more additional projection images by performing a dark field image subtraction. ### Claim 6 (depends on 1) The method according to claim 1, wherein the performing includes calculating a cumulative histogram of said pilot projection image and removing contributions by at least one of (i)defective pixels, (ii)metal regions of the object to be imaged and (iii)tissue regions of the object to be imaged to said cumulative histogram and, wherein the removing further includes at least one of (i)determining a pilot projection image range and (ii)calculating a high threshold and a low threshold using the determined pilot projection image range. ### Claim 7 (depends on 6) The method according to claim 6, wherein the estimating further includes determining a median gray level value of pixels between the determined high and low thresholds, wherein the median gray level value represents teeth and trabeculae. ### Claim 8 (depends on 7) The method according to claim 7, wherein the estimating further includes determining an estimated optimal exposure time using a target value, the determined median gray level value and a pilot projection image exposure time. ### Claim 9 (depends on 1) The method according to claim 1, further comprising processing the one or more final images by applying gain and bad pixel correction. ### Claim 10 (depends on 1) The method according to claim 1, further comprising displaying at least one of the one or more final images and an exposure quality on a display unit. ### Claim 11 A system for automatically determining a required exposure time for an intraoral x-ray image, the system comprising: at least one processor operable to: acquire a low dose pilot projection image of an object to be imaged; perform a sanity check to ensure that a usable exposure is attainable; estimate a remaining required exposure time for obtaining one or more additional projection images by determining that one or more final images will not be saturated by computing an estimated saturation exposure time required for saturation of an x-ray detector, and comparing said estimated saturation exposure time required for saturation with at least one of an estimated optimal exposure time and a maximum possible exposure time and responsive to determining that the one or more final images will not be saturated, obtain the one or more additional projection images for one or more final images using the estimated remaining required exposure time such that a dose delivered to the x-ray detector is influenced by patient specific dental anatomy. ### Claim 12 (depends on 11) The system according to claim 11, wherein the processor is operable to perform x-ray imaging and wherein the pilot projection image and one additional projection image are combined to form one final image. ### Claim 13 (depends on 11) The system according to claim 11, wherein the processor is operable to perform tomosynthesis imaging wherein the one or more additional projection images are final images and wherein the final images are reconstructed into tomographic images, and wherein the tomographic images are tomosynthesis images. ### Claim 14 (depends on 11) The system according to claim 11, wherein the processor is operable to perform a setup comprising selecting an expectation of an image quality wherein the image quality is discrete or according to a sliding scale. ### Claim 15 (depends on 11) The system according to claim 11, wherein the processor is operable to further process the pilot projection image and the one or more additional projection images by performing a dark field image subtraction. ### Claim 16 (depends on 11) The system according to claim 11, wherein the processor is operable to calculate a cumulative histogram of said pilot projection image and to remove contributions by at least one of (i)defective pixels, (ii)metal regions of the object to be imaged and (iii)tissue regions of the object to be imaged to said cumulative histogram and, wherein the removing by the processor further includes at least one of (i)determining a pilot projection image range and (ii)calculating a high threshold and a low threshold using the determined pilot projection image range. ### Claim 17 (depends on 16) The system according to claim 16, wherein the processor is further operable to determine a median gray level value of pixels between the determined high and low thresholds, wherein the median gray level value represents teeth and trabeculae. ### Claim 18 (depends on 17) The system according to claim 17, wherein the processor is further operable to determine an estimated optimal exposure time using a target value, the determined median gray level value and a pilot projection image exposure time. ### Claim 19 (depends on 11) The system according to claim 11, wherein the processor is operable to provide at least one of the one or more final images and an exposure quality to a display unit. ### Claim 20 A non-transitory computer-readable storage medium storing a program which, when executed by a computer system, causes the computer system to perform a procedure comprising: acquiring a low dose pilot projection image of an object to be imaged; performing a sanity check to ensure that a usable exposure is attainable; estimating a remaining required exposure time for obtaining one or more additional projection images, the estimating including determining that one or more final images will not be saturated by computing an estimated saturation exposure time required for saturation of an x-ray detector, and comparing said estimated saturation exposure time required for saturation with at least one of an estimated optimal exposure time and a maximum possible exposure time and responsive to determining that the one or more final images will not be saturated, obtaining the one or more additional projection images for one or more final images using the estimated remaining required exposure time such that a dose delivered to the x-ray detector is influenced by patient specific dental anatomy.