title: Interventional Cone-Beam CT with Arbitrary Acquisition Orbits: Simulation and Reconstruction
creator: Russ, Tom
subject: ddc-530
subject: 530 Physics
description: Cone-beam CT (CBCT) is commonly used in image-guided surgery due to its speed, mobility and spatial resolution. The advent of robotic interventional X-ray systems has opened the door to dramatically increased flexibility in the design of CBCT acquisition orbits. Alternative orbits allow to steer the CBCT system around interfering surgical equipment and to avoid radiopaque structures near imaging tasks to improve image quality. Due to time constraints in the operating room, real-time algorithms to determine the ideal acquisition geometry and reconstruct the corresponding projection data are needed to implement arbitrary trajectories in clinical practice.  In this thesis, the best alternative to a standard circular orbit is determined by simulating CBCT images using a projection operator approach, which is validated with robust Monte Carlo (MC) simulations. The predictions of both simulation methods coincide, with the projection operator approach requiring only seven minutes.  Second, a method for fast reconstruction of arbitrary orbits based on convolutional neural networks (CNNs) is presented. The proposed reconstruction technique provides similar image quality (nRMSE=0.060) when compared to state-of-the-art reconstructions (nRMSE=0.045), while drastically reducing the computation time by 90%.   The presented work develops fast methods to determine suitable alternatives to the standard circular orbit and to provide adequate reconstructions. These methods facilitate the implementation of arbitrary CBCT orbits to increase flexibility and precision during image-guided procedures.
date: 2022
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/30880/1/PhD_Russ%20Print.pdf
identifier: DOI:10.11588/heidok.00030880
identifier: urn:nbn:de:bsz:16-heidok-308803
identifier:   Russ, Tom  (2022) Interventional Cone-Beam CT with Arbitrary Acquisition Orbits: Simulation and Reconstruction.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/30880/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng