US 12,303,340 B2
Calibration of 2D images for digital templating using monomarker
Christoph K. Boese, Hamburg (DE)
Assigned to Smith & Nephew, Inc., Memphis, TN (US); Smith & Nephew Asia Pacific Pte. Limited, Singapore (SG); and Smith & Nephew Orthopaedics AG, Zug (CH)
Filed by Smith & Nephew, Inc., Memphis, TN (US); Smith & Nephew Asia Pacific Pte. Limited, Singapore (SG); and Smith & Nephew Orthopaedics AG, Zug (CH)
Filed on May 29, 2024, as Appl. No. 18/676,908.
Application 18/676,908 is a continuation of application No. 17/524,349, filed on Nov. 11, 2021, granted, now 12,016,736.
Prior Publication US 2024/0307146 A1, Sep. 19, 2024
Int. Cl. A61B 90/00 (2016.01); A61B 34/10 (2016.01); G06T 7/80 (2017.01)
CPC A61B 90/36 (2016.02) [A61B 34/10 (2016.02); G06T 7/80 (2017.01); A61B 2034/105 (2016.02); A61B 2090/363 (2016.02); A61B 2090/367 (2016.02); G06T 2207/30008 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A system for calibration of a 2D image of a pelvis of a patient, the system comprising:
a calibration device comprising:
a base configured to be positioned proximate a suprapubic region of the patient, and
a single fiducial marker coupled to the base, wherein the single fiducial marker is configured to be positioned at a suprapubic region of the patient;
at least one processor; and
a non-transitory, computer-readable medium storing instructions that, when executed, cause the at least one processor to:
receive a frontal 2D image of the pelvis and a lateral 2D image of the pelvis, each 2D image captured by an imaging detector with the single fiducial marker positioned on the suprapubic region of the patient, wherein the frontal 2D image comprises a first representation of the single fiducial marker and the lateral 2D image comprises a second representation of the single fiducial marker,
measure a diameter of the first representation of the single fiducial marker in the frontal 2D image and a diameter of the second representation of the single fiducial marker in the lateral 2D image,
determine, based on the diameter of the first representation and a known diameter of the single fiducial marker, a first distance of the single fiducial marker from the imaging detector,
determine, based on the diameter of the second representation and the known diameter of the single fiducial marker, a second distance of the single fiducial marker from a coronal plane of the pelvis in the lateral 2D image,
modify the second distance based on a rotational offset of the patient in the lateral 2D image,
determine, based on the first distance and the modified second distance, a third distance of the coronal plane from the imaging detector in the frontal 2D image,
determine, based on the third distance, a calibration factor for the frontal 2D image,
scale the frontal 2D image based on the calibration factor, and
output the scaled frontal 2D image to a computer-readable storage device.