A Uneri1, X Zhang1, J W Stayman1, P A Helm2, G M Osgood3, N Theodore4, J H Siewerdsen1,4. 1. Department of Biomedical Engineering, Johns Hopkins University, Baltimore MD. 2. Medtronic Inc., Littleton MA. 3. Department of Orthopaedic Surgery, Johns Hopkins Medicine, Baltimore MD. 4. Department of Neurosurgery, Johns Hopkins Medicine, Baltimore MD.
Abstract
PURPOSE: Intraoperative 2D virtual long-film (VLF) imaging is investigated for 3D guidance and confirmation of the surgical product in spinal deformity correction. Multi-slot-scan geometry (rather than a single-slot "topogram") is exploited to produce parallax views of the scene for accurate 3D colocalization from a single radiograph. METHODS: The multi-slot approach uses additional angled collimator apertures to form fan-beams with disparate views (parallax) of anatomy and instrumentation and to extend field-of-view beyond the linear motion limits. Combined with a knowledge of surgical implants (pedicle screws and/or spinal rods modeled as "known components"), 3D-2D image registration is used to solve for pose estimates via optimization of image gradient correlation. Experiments were conducted in cadaver studies emulating the system geometry of the O-arm (Medtronic, Minneapolis MN). RESULTS: Experiments demonstrated feasibility of multi-slot VLF and quantified the geometric accuracy of 3D-2D registration using VLF acquisitions. Registration of pedicle screws from a single VLF yielded mean target registration error of (2.0±0.7) mm, comparable to the accuracy of surgical trackers and registration using multiple radiographs (e.g., AP and LAT). CONCLUSIONS: 3D-2D registration in a single VLF image offers a promising new solution for image guidance in spinal deformity correction. The ability to accurately resolve pose from a single view absolves workflow challenges of multiple-view registration and suggests application beyond spine surgery, such as reduction of long-bone fractures.
PURPOSE: Intraoperative 2D virtual long-film (VLF) imaging is investigated for 3D guidance and confirmation of the surgical product in spinal deformity correction. Multi-slot-scan geometry (rather than a single-slot "topogram") is exploited to produce parallax views of the scene for accurate 3D colocalization from a single radiograph. METHODS: The multi-slot approach uses additional angled collimator apertures to form fan-beams with disparate views (parallax) of anatomy and instrumentation and to extend field-of-view beyond the linear motion limits. Combined with a knowledge of surgical implants (pedicle screws and/or spinal rods modeled as "known components"), 3D-2D image registration is used to solve for pose estimates via optimization of image gradient correlation. Experiments were conducted in cadaver studies emulating the system geometry of the O-arm (Medtronic, Minneapolis MN). RESULTS: Experiments demonstrated feasibility of multi-slot VLF and quantified the geometric accuracy of 3D-2D registration using VLF acquisitions. Registration of pedicle screws from a single VLF yielded mean target registration error of (2.0±0.7) mm, comparable to the accuracy of surgical trackers and registration using multiple radiographs (e.g., AP and LAT). CONCLUSIONS: 3D-2D registration in a single VLF image offers a promising new solution for image guidance in spinal deformity correction. The ability to accurately resolve pose from a single view absolves workflow challenges of multiple-view registration and suggests application beyond spine surgery, such as reduction of long-bone fractures.
Authors: Bernd Bittersohl; Joana Freitas; Daniela Zaps; Matthew R Schmitz; James D Bomar; Abd R Muhamad; Harish S Hosalkar Journal: J Bone Joint Surg Am Date: 2013-05-01 Impact factor: 5.284
Authors: Brice Ilharreborde; Jean Sebastien Steffen; Eric Nectoux; Jean Marc Vital; Keyvan Mazda; Wafa Skalli; Ibrahim Obeid Journal: Spine (Phila Pa 1976) Date: 2011-09-15 Impact factor: 3.468
Authors: A Uneri; T De Silva; J Goerres; M W Jacobson; M D Ketcha; S Reaungamornrat; G Kleinszig; S Vogt; A J Khanna; G M Osgood; J-P Wolinsky; J H Siewerdsen Journal: Phys Med Biol Date: 2017-02-24 Impact factor: 3.609