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46 results on '"Vogt, S."'

1. Surgical navigation for guidewire placement from intraoperative fluoroscopy in orthopaedic surgery.

Author

Mekki, L, Sheth, N M, Vijayan, R C, Rohleder, M, Sisniega, A, Kleinszig, G, Vogt, S, Kunze, H, Osgood, G M, Siewerdsen, J H, and Uneri, A

Subjects
ORTHOPEDIC surgery, FLUOROSCOPY, GEOMETRIC modeling, NAVIGATION, RADIATION doses, MEDICAL cadavers
Abstract

Objective. Surgical guidewires are commonly used in placing fixation implants to stabilize fractures. Accurate positioning of these instruments is challenged by difficulties in 3D reckoning from 2D fluoroscopy. This work aims to enhance the accuracy and reduce exposure times by providing 3D navigation for guidewire placement from as little as two fluoroscopic images. Approach. Our approach combines machine learning-based segmentation with the geometric model of the imager to determine the 3D poses of guidewires. Instrument tips are encoded as individual keypoints, and the segmentation masks are processed to estimate the trajectory. Correspondence between detections in multiple views is established using the pre-calibrated system geometry, and the corresponding features are backprojected to obtain the 3D pose. Guidewire 3D directions were computed using both an analytical and an optimization-based method. The complete approach was evaluated in cadaveric specimens with respect to potential confounding effects from the imaging geometry and radiographic scene clutter due to other instruments. Main results. The detection network identified the guidewire tips within 2.2 mm and guidewire directions within 1.1°, in 2D detector coordinates. Feature correspondence rejected false detections, particularly in images with other instruments, to achieve 83% precision and 90% recall. Estimating the 3D direction via numerical optimization showed added robustness to guidewires aligned with the gantry rotation plane. Guidewire tips and directions were localized in 3D world coordinates with a median accuracy of 1.8 mm and 2.7°, respectively. Significance. The paper reports a new method for automatic 2D detection and 3D localization of guidewires from pairs of fluoroscopic images. Localized guidewires can be virtually overlaid on the patient's pre-operative 3D scan during the intervention. Accurate pose determination for multiple guidewires from two images offers to reduce radiation dose by minimizing the need for repeated imaging and provides quantitative feedback prior to implant placement. [ABSTRACT FROM AUTHOR]

Published
2023
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3. 3D–2D image registration in the presence of soft-tissue deformation in image-guided transbronchial interventions.

Author

Vijayan, R, Sheth, N, Mekki, L, Lu, A, Uneri, A, Sisniega, A, Magaraggia, J, Kleinszig, G, Vogt, S, Thiboutot, J, Lee, H, Yarmus, L, and Siewerdsen, J H

Subjects
IMAGE registration, LUNGS, CONE beam computed tomography, PULMONARY nodules, RANGE of motion of joints, FLUOROSCOPY, IMAGE reconstruction algorithms
Abstract

Purpose. Target localization in pulmonary interventions (e.g. transbronchial biopsy of a lung nodule) is challenged by deformable motion and may benefit from fluoroscopic overlay of the target to provide accurate guidance. We present and evaluate a 3D–2D image registration method for fluoroscopic overlay in the presence of tissue deformation using a multi-resolution/multi-scale (MRMS) framework with an objective function that drives registration primarily by soft-tissue image gradients. Methods. The MRMS method registers 3D cone-beam CT to 2D fluoroscopy without gating of respiratory phase by coarse-to-fine resampling and global-to-local rescaling about target regions-of-interest. A variation of the gradient orientation ( GO) similarity metric (denoted G O ′ ) was developed to downweight bone gradients and drive registration via soft-tissue gradients. Performance was evaluated in terms of projection distance error at isocenter (PDEiso). Phantom studies determined nominal algorithm parameters and capture range. Preclinical studies used a freshly deceased, ventilated porcine specimen to evaluate performance in the presence of real tissue deformation and a broad range of 3D–2D image mismatch. Results. Nominal algorithm parameters were identified that provided robust performance over a broad range of motion (0–20 mm), including an adaptive parameter selection technique to accommodate unknown mismatch in respiratory phase. The G O ′ metric yielded median PDEiso = 1.2 mm, compared to 6.2 mm for conventional GO. Preclinical studies with real lung deformation demonstrated median PDEiso = 1.3 mm with MRMS + G O ′ registration, compared to 2.2 mm with a conventional transform. Runtime was 26 s and can be reduced to 2.5 s given a prior registration within ∼5 mm as initialization. Conclusions. MRMS registration via soft-tissue gradients achieved accurate fluoroscopic overlay in the presence of deformable lung motion. By driving registration via soft-tissue image gradients, the method avoided false local minima presented by bones and was robust to a wide range of motion magnitude. [ABSTRACT FROM AUTHOR]

Published
2023
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4. C-arm orbits for metal artifact avoidance (MAA) in cone-beam CT

Author

Wu, P, primary, Sheth, N, additional, Sisniega, A, additional, Uneri, A, additional, Han, R, additional, Vijayan, R, additional, Vagdargi, P, additional, Kreher, B, additional, Kunze, H, additional, Kleinszig, G, additional, Vogt, S, additional, Lo, S -F, additional, Theodore, N, additional, and Siewerdsen, J H, additional

Published
2020
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8. A line fiducial method for geometric calibration of cone-beam CT systems with diverse scan trajectories

Author

Jacobson, M W, primary, Ketcha, M D, additional, Capostagno, S, additional, Martin, A, additional, Uneri, A, additional, Goerres, J, additional, De Silva, T, additional, Reaungamornrat, S, additional, Han, R, additional, Manbachi, A, additional, Stayman, J W, additional, Vogt, S, additional, Kleinszig, G, additional, and Siewerdsen, J H, additional

Published
2018
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14. The ATLAS IBL CO2cooling system

Author

Verlaat, B., primary, Ostrega, M., additional, Zwalinski, L., additional, Bortolin, C., additional, Vogt, S., additional, Godlewski, J., additional, Crespo-Lopez, O., additional, Overbeek, M. Van, additional, and Blaszcyk, T., additional

Published
2017
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22. Performance of the electronic readout of the ATLAS liquid argon calorimeters

Author

Abreu, H, primary, Aharrouche, M, additional, Aleksa, M, additional, Aperio-Bella, L, additional, Archambault, J P, additional, Arfaoui, S, additional, Arnaez, O, additional, Auge, E, additional, Aurousseau, M, additional, Bahinipati, S, additional, Ban, J, additional, Banfi, D, additional, Barajas, A, additional, Barillari, T, additional, Bazan, A, additional, Bellachia, F, additional, Beloborodova, O, additional, Benchekroun, D, additional, Benslama, K, additional, Berger, N, additional, Berghaus, F, additional, Bernat, P, additional, Bernier, R, additional, Besson, N, additional, Binet, S, additional, Blanchard, J B, additional, Blondel, A, additional, Bobrovnikov, V, additional, Bohner, O, additional, Boonekamp, M, additional, Bordoni, S, additional, Bouchel, M, additional, Bourdarios, C, additional, Bozzone, A, additional, Braun, H M, additional, Breton, D, additional, Brettel, H, additional, Brooijmans, G, additional, Caputo, R, additional, Carli, T, additional, Carminati, L, additional, Caughron, S, additional, Cavalleri, P, additional, Cavalli, D, additional, Chareyre, E, additional, Chase, R L, additional, Chekulaev, S V, additional, Chen, H, additional, Cheplakov, A, additional, Chiche, R, additional, Citterio, M, additional, Cojocaru, C, additional, Colas, J, additional, Collard, C, additional, Collot, J, additional, Consonni, M, additional, Cooke, M, additional, Copic, K, additional, Costa, G C, additional, Courneyea, L, additional, Cuisy, D, additional, Cwienk, W D, additional, Damazio, D, additional, Dannheim, D, additional, Cecco, S De, additional, Broise, X De la, additional, Taille, C De La, additional, Vivie, J B De, additional, Debennerot, B, additional, Delagnes, E, additional, Delmastro, M, additional, Derue, F, additional, Dhaliwal, S, additional, Ciaccio, L Di, additional, Doan, O, additional, Dudziak, F, additional, Duflot, L, additional, Dumont-Dayot, N, additional, Dzahini, D, additional, Elles, S, additional, Ertel, E, additional, Escalier, M, additional, Etienvre, A I, additional, Falleau, I, additional, Fanti, M, additional, Farooque, T, additional, Favre, P, additional, Fayard, Lo, additional, Fent, J, additional, Ferencei, J, additional, Fischer, A, additional, Fournier, D, additional, Fournier, L, additional, Fras, M, additional, Froeschl, R, additional, Gadfort, T, additional, Martel, M L Gallin, additional, Gibson, A, additional, Gillberg, D, additional, Gingrich, D M, additional, Goepfert, T, additional, Goodson, J, additional, Gouighri, M, additional, Goy, C, additional, Grassi, V, additional, Gray, J, additional, Guillemin, T, additional, Guo, B, additional, Habring, J, additional, Handel, C, additional, Heelan, L, additional, Heintz, H, additional, Helary, L, additional, Henrot-Versille, S, additional, Hervas, L, additional, Hobbs, J, additional, Hoffman, J, additional, Hostachy, J Y, additional, Hoummada, A, additional, Hrivnac, J, additional, Hrynova, T, additional, Hubaut, F, additional, Huber, J, additional, Iconomidou-Fayard, L, additional, Iengo, P, additional, Imbert, P, additional, Ishmukhametov, R, additional, Jantsch, A, additional, Javadov, N, additional, Jézéquel, S, additional, Belenguer, M Jimenez, additional, Ju, X Y, additional, Kado, M, additional, Kalinowski, A, additional, Kar, D, additional, Karev, A, additional, Katsanos, I, additional, Kazarinov, M, additional, Kerschen, N, additional, Kierstead, J, additional, Kim, M S, additional, Kiryunin, A, additional, Kladiva, E, additional, Knecht, N, additional, Kobel, M, additional, Koletsou, I, additional, König, S, additional, Krieger, P, additional, Kukhtin, V, additional, Kuna, M, additional, Kurchaninov, L, additional, Labbé, J, additional, Lacour, D, additional, Ladygin, E, additional, Lafaye, R, additional, Laforge, B, additional, Lamarra, D, additional, Lampl, W, additional, Lanni, F, additional, Laplace, S, additional, Laskus, H, additional, Coguie, A Le, additional, Dortz, O Le, additional, Maner, C Le, additional, Lechowski, M, additional, Lee, S C, additional, Lefebvre, M, additional, Leonhardt, K, additional, Lethiec, L, additional, Leveque, J, additional, Liang, Z, additional, Liu, Ch, additional, Liu, T, additional, Liu, Y, additional, Loch, P, additional, Lu, J, additional, Ma, H, additional, Mader, W, additional, Majewski, S, additional, Makovec, N, additional, Makowiecki, D, additional, Mandelli, L, additional, Mangeard, P S, additional, Mansoulié, B, additional, Marchand, J F, additional, Marchiori, G, additional, Martin, D, additional, Martin-Chassard, G, additional, Latour, B Martin dit, additional, Marzin, A, additional, Maslennikov, A, additional, Massol, N, additional, Matricon, P, additional, Maximov, D, additional, Mazzanti, M, additional, McCarthy, T, additional, McPherson, R, additional, Menke, S, additional, Meyer, J P, additional, Ming, Y, additional, Monnier, E, additional, Mooshofer, P, additional, Neganov, A, additional, Niedercorn, F, additional, Nikolic-Audit, I, additional, Nugent, I M, additional, Oakham, G, additional, Oberlack, H, additional, Ocariz, J, additional, Odier, J, additional, Oram, C J, additional, Orlov, I, additional, Orr, R, additional, Parsons, J A, additional, Peleganchuk, S, additional, Penson, A, additional, Perini, L, additional, Perrodo, P, additional, Perrot, G, additional, Perus, A, additional, Petit, E, additional, Pisarev, I, additional, Plamondon, M, additional, Poffenberger, P, additional, Poggioli, L, additional, Pospelov, G, additional, Pralavorio, P, additional, Prast, J, additional, Prudent, X, additional, Przysiezniak, H, additional, Puzo, P, additional, Quentin, M, additional, Radeka, V, additional, Rajagopalan, S, additional, Rauter, E, additional, Reimann, O, additional, Rescia, S, additional, Resende, B, additional, Richer, J P, additional, Ridel, M, additional, Rios, R, additional, Roos, L, additional, Rosenbaum, G, additional, Rosenzweig, H, additional, Rossetto, O, additional, Roudil, W, additional, Rousseau, D, additional, Ruan, X, additional, Rudert, A, additional, Rusakovich, N, additional, Rusquart, P, additional, Rutherfoord, J, additional, Sauvage, G, additional, Savine, A, additional, Schaarschmidt, J, additional, Schacht, P, additional, Schaffer, A, additional, Schram, M, additional, Schwemling, P, additional, Moreau, N Seguin, additional, Seifert, F, additional, Serin, L, additional, Seuster, R, additional, Shalyugin, A, additional, Shupe, M, additional, Simion, S, additional, Sinervo, P, additional, Sippach, W, additional, Skovpen, K, additional, Sliwa, R, additional, Soukharev, A, additional, Spano, F, additional, Stavina, P, additional, Straessner, A, additional, Strizenec, P, additional, Stroynowski, R, additional, Talyshev, A, additional, Tapprogge, S, additional, Tarrade, F, additional, Tartarelli, G F, additional, Teuscher, R, additional, Tikhonov, Yu, additional, Tocut, V, additional, Tompkins, D, additional, Thompson, P, additional, Tisserant, S, additional, Todorov, T, additional, Tomasz, F, additional, Trincaz-Duvoid, S, additional, Thi, N Trinh, additional, Trochet, S, additional, Trocmé, B, additional, Tschann-Grimm, K, additional, Tsionou, D, additional, Ueno, R, additional, Unal, G, additional, Urbaniec, D, additional, Usov, Y, additional, Voss, K, additional, Veillet, J J, additional, Vincter, M, additional, Vogt, S, additional, Weng, Z, additional, Whalen, K, additional, Wicek, F, additional, Wilkens, H, additional, Wingerter-Seez, I, additional, Wulf, E, additional, Yang, Z, additional, Ye, J, additional, Yuan, L, additional, Yurkewicz, A, additional, Zarzhitsky, P, additional, Zerwas, D, additional, Zhang, H, additional, Zhang, L, additional, Zhou, N, additional, Zimmer, J, additional, Zitoun, R, additional, and Zivkovic, L, additional

Published
2010
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24. Exoplanet properties from Lick, Keck and AAT

Author

Marcy, G W, primary, Butler, R P, additional, Vogt, S S, additional, Fischer, D A, additional, Wright, J T, additional, Johnson, J A, additional, Tinney, C G, additional, Jones, H R A, additional, Carter, B D, additional, Bailey, J, additional, O'Toole, S J, additional, and Upadhyay, S, additional

Published
2008
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25. The M Dwarf GJ 436 and its Neptune‐Mass Planet

Author

Maness, H. L., primary, Marcy, G. W., additional, Ford, E. B., additional, Hauschildt, P. H., additional, Shreve, A. T., additional, Basri, G. B., additional, Butler, R. P., additional, and Vogt, S. S., additional

Published
2007
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27. 3D–2D registration for surgical guidance: effect of projection view angles on registration accuracy.

Author

Uneri, A, Otake, Y, Wang, A S, Kleinszig, G, Vogt, S, Khanna, A J, and Siewerdsen, J H

Subjects
COMPUTER-assisted surgery, IMAGE registration, THREE-dimensional display systems, INTENSITY modulated radiotherapy, SURGERY
Abstract

An algorithm for intensity-based 3D–2D registration of CT and x-ray projections is evaluated, specifically using single- or dual-projection views to provide 3D localization. The registration framework employs the gradient information similarity metric and covariance matrix adaptation evolution strategy to solve for the patient pose in six degrees of freedom. Registration performance was evaluated in an anthropomorphic phantom and cadaver, using C-arm projection views acquired at angular separation, Δθ, ranging from ∼0°–180° at variable C-arm magnification. Registration accuracy was assessed in terms of 2D projection distance error and 3D target registration error (TRE) and compared to that of an electromagnetic (EM) tracker. The results indicate that angular separation as small as Δθ ∼10°–20° achieved TRE <2 mm with 95% confidence, comparable or superior to that of the EM tracker. The method allows direct registration of preoperative CT and planning data to intraoperative fluoroscopy, providing 3D localization free from conventional limitations associated with external fiducial markers, stereotactic frames, trackers and manual registration. [ABSTRACT FROM AUTHOR]

Published
2014
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31. Four New Exoplanets and Hints of Additional Substellar Companions to Exoplanet Host StarsBased on observations obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Mauna Kea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain.

Author

Wright, J. T., Marcy, G. W., Fischer, D. A, Butler, R. P., Vogt, S. S., Tinney, C. G., Jones, H. R. A., Carter, B. D., Johnson, J. A., McCarthy, C., and Apps, K.

Published
2007
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37. THE ANGLO-AUSTRALIAN PLANET SEARCH. XXII. TWO NEW MULTI-PLANET SYSTEMS.

Author

Wittenmyer, Robert A., Horner, J., Tuomi, Mikko, Salter, G. S., Tinney, C. G., Butler, R. P., Jones, H. R. A., O’Toole, S. J., Bailey, J., Carter, B. D., Jenkins, J. S., Zhang, Z., Vogt, S. S., and Rivera, Eugenio J.

Subjects
PLANETARY research, PLANETARY observations, PLANETARY orbits, RADIAL velocity of stars, NATURAL satellites
Abstract

We report the detection of two new planets from the Anglo-Australian Planet Search. These planets orbit two stars each previously known to host one planet. The new planet orbiting HD 142 has a period of 6005 ± 427 days, and a minimum mass of 5.3 MJup. HD 142c is thus a new Jupiter analog: a gas-giant planet with a long period and low eccentricity (e = 0.21 ± 0.07). The second planet in the HD 159868 system has a period of 352.3 ± 1.3 days and m sin i = 0.73 ± 0.05 MJup. In both of these systems, including the additional planets in the fitting process significantly reduced the eccentricity of the original planet. These systems are thus examples of how multiple-planet systems can masquerade as moderately eccentric single-planet systems. [ABSTRACT FROM AUTHOR]

Published
2012
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40. Catalog of Nearby Exoplanets.

Author

Butler, R. P., Wright, J. T., Marcy, G. W., Fischer, D. A., Vogt, S. S., Tinney, C. G., Jones, H. R. A., Carter, B. D., Johnson, J. A., McCarthy, C., and Penny, A. J.

Published
2006
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44. 3D–2D registration in mobile radiographs: algorithm development and preliminary clinical evaluation.

Author

Otake Y, Wang AS, Uneri A, Kleinszig G, Vogt S, Aygun N, Lo SF, Wolinsky JP, Gokaslan ZL, and Siewerdsen JH

Subjects
Abdomen, Cadaver, Computer Simulation, Humans, Phantoms, Imaging, Retrospective Studies, Algorithms, Fluoroscopy methods, Imaging, Three-Dimensional methods, Pelvis diagnostic imaging, Radiography, Thoracic, Spine diagnostic imaging, Tomography, X-Ray Computed methods
Abstract

An image-based 3D-2D registration method is presented using radiographs acquired in the uncalibrated, unconstrained geometry of mobile radiography. The approach extends a previous method for six degree-of-freedom (DOF) registration in C-arm fluoroscopy (namely 'LevelCheck') to solve the 9-DOF estimate of geometry in which the position of the source and detector are unconstrained. The method was implemented using a gradient correlation similarity metric and stochastic derivative-free optimization on a GPU. Development and evaluation were conducted in three steps. First, simulation studies were performed that involved a CT scan of an anthropomorphic body phantom and 1000 randomly generated digitally reconstructed radiographs in posterior-anterior and lateral views. A median projection distance error (PDE) of 0.007 mm was achieved with 9-DOF registration compared to 0.767 mm for 6-DOF. Second, cadaver studies were conducted using mobile radiographs acquired in three anatomical regions (thorax, abdomen and pelvis) and three levels of source-detector distance (~800, ~1000 and ~1200 mm). The 9-DOF method achieved a median PDE of 0.49 mm (compared to 2.53 mm for the 6-DOF method) and demonstrated robustness in the unconstrained imaging geometry. Finally, a retrospective clinical study was conducted with intraoperative radiographs of the spine exhibiting real anatomical deformation and image content mismatch (e.g. interventional devices in the radiograph that were not in the CT), demonstrating a PDE = 1.1 mm for the 9-DOF approach. Average computation time was 48.5 s, involving 687 701 function evaluations on average, compared to 18.2 s for the 6-DOF method. Despite the greater computational load, the 9-DOF method may offer a valuable tool for target localization (e.g. decision support in level counting) as well as safety and quality assurance checks at the conclusion of a procedure (e.g. overlay of planning data on the radiograph for verification of the surgical product) in a manner consistent with natural surgical workflow.

Published
2015
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45. Soft-tissue imaging with C-arm cone-beam CT using statistical reconstruction.

Author

Wang AS, Stayman JW, Otake Y, Kleinszig G, Vogt S, Gallia GL, Khanna AJ, and Siewerdsen JH

Subjects
Head diagnostic imaging, Humans, Phantoms, Imaging, Radiography, Abdominal, Signal-To-Noise Ratio, Torso diagnostic imaging, Cone-Beam Computed Tomography methods, Image Processing, Computer-Assisted methods
Abstract

The potential for statistical image reconstruction methods such as penalized-likelihood (PL) to improve C-arm cone-beam CT (CBCT) soft-tissue visualization for intraoperative imaging over conventional filtered backprojection (FBP) is assessed in this work by making a fair comparison in relation to soft-tissue performance. A prototype mobile C-arm was used to scan anthropomorphic head and abdomen phantoms as well as a cadaveric torso at doses substantially lower than typical values in diagnostic CT, and the effects of dose reduction via tube current reduction and sparse sampling were also compared. Matched spatial resolution between PL and FBP was determined by the edge spread function of low-contrast (∼ 40-80 HU) spheres in the phantoms, which were representative of soft-tissue imaging tasks. PL using the non-quadratic Huber penalty was found to substantially reduce noise relative to FBP, especially at lower spatial resolution where PL provides a contrast-to-noise ratio increase up to 1.4-2.2 × over FBP at 50% dose reduction across all objects. Comparison of sampling strategies indicates that soft-tissue imaging benefits from fully sampled acquisitions at dose above ∼ 1.7 mGy and benefits from 50% sparsity at dose below ∼ 1.0 mGy. Therefore, an appropriate sampling strategy along with the improved low-contrast visualization offered by statistical reconstruction demonstrates the potential for extending intraoperative C-arm CBCT to applications in soft-tissue interventions in neurosurgery as well as thoracic and abdominal surgeries by overcoming conventional tradeoffs in noise, spatial resolution, and dose.

Published
2014
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46. Robust 3D-2D image registration: application to spine interventions and vertebral labeling in the presence of anatomical deformation.

Author

Otake Y, Wang AS, Webster Stayman J, Uneri A, Kleinszig G, Vogt S, Khanna AJ, Gokaslan ZL, and Siewerdsen JH

Subjects
Humans, Spine surgery, Fluoroscopy methods, Imaging, Three-Dimensional methods, Spine abnormalities, Spine diagnostic imaging, Tomography, X-Ray Computed methods
Abstract

We present a framework for robustly estimating registration between a 3D volume image and a 2D projection image and evaluate its precision and robustness in spine interventions for vertebral localization in the presence of anatomical deformation. The framework employs a normalized gradient information similarity metric and multi-start covariance matrix adaptation evolution strategy optimization with local-restarts, which provided improved robustness against deformation and content mismatch. The parallelized implementation allowed orders-of-magnitude acceleration in computation time and improved the robustness of registration via multi-start global optimization. Experiments involved a cadaver specimen and two CT datasets (supine and prone) and 36 C-arm fluoroscopy images acquired with the specimen in four positions (supine, prone, supine with lordosis, prone with kyphosis), three regions (thoracic, abdominal, and lumbar), and three levels of geometric magnification (1.7, 2.0, 2.4). Registration accuracy was evaluated in terms of projection distance error (PDE) between the estimated and true target points in the projection image, including 14 400 random trials (200 trials on the 72 registration scenarios) with initialization error up to ±200 mm and ±10°. The resulting median PDE was better than 0.1 mm in all cases, depending somewhat on the resolution of input CT and fluoroscopy images. The cadaver experiments illustrated the tradeoff between robustness and computation time, yielding a success rate of 99.993% in vertebral labeling (with 'success' defined as PDE <5 mm) using 1,718 664 ± 96 582 function evaluations computed in 54.0 ± 3.5 s on a mid-range GPU (nVidia, GeForce GTX690). Parameters yielding a faster search (e.g., fewer multi-starts) reduced robustness under conditions of large deformation and poor initialization (99.535% success for the same data registered in 13.1 s), but given good initialization (e.g., ±5 mm, assuming a robust initial run) the same registration could be solved with 99.993% success in 6.3 s. The ability to register CT to fluoroscopy in a manner robust to patient deformation could be valuable in applications such as radiation therapy, interventional radiology, and an assistant to target localization (e.g., vertebral labeling) in image-guided spine surgery.

Published
2013
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