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Gomez-Sarmiento IN, Tho D, Dürrbeck C, de Jager W, Laurendeau D, Beaulieu L. Accuracy of an electromagnetic tracking enabled afterloader based on the automated registration with CT phantom images. Med Phys 2024; 51:799-808. [PMID: 38127342 DOI: 10.1002/mp.16903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Revised: 12/05/2023] [Accepted: 12/08/2023] [Indexed: 12/23/2023] Open
Abstract
BACKGROUND Electromagnetic tracking (EMT) has been researched for brachytherapy applications, showing a great potential for automating implant reconstruction, and overcoming image-based limitations such as contrast and spatial resolution. One of the challenges of this technology is that it does not intrinsically share the same reference frame as the patient's medical imaging. PURPOSE To present a novel phantom that can be used for a comprehensive quality assurance (QA) program of brachytherapy EMT systems and use this phantom to validate a novel applicator-based registration method of EMT and image reference frames for gynecological (GYN) interstitial brachytherapy. MATERIALS AND METHODS Eleven 6F-catheters (20 cm long), one 6F round tip catheter (29.4 cm long) and a tandem and ring gynecological applicator (Elekta, CT/MR 60°, 40 mm long tandem, 30 mm diameter ring) were placed in a rigid custom-made phantom (Elekta Brachytherapy, Veenendaal, The Netherlands) to reconstruct their geometry using a five-degree of freedom EMT sensor attached to an afterloader's check cable. All EMT reconstructions were done in three different environments: disturbance free (no metal nearby), computed tomography (CT)-on-rails brachytherapy suite and magnetic resonance imaging (MRI) brachytherapy suite. Implants were placed parallel to a magnetic field generatorand were reconstructed using two different acquisition methods: step-and-record and continuous motion. In all cases, the acquisition is performed at a rate of approximately 40 Hz. A CT scan of the phantom inside a water cube was obtained. In the treatment planning system (TPS), all catheters in the CT images were manually reconstructed and the applicator reconstruction was achieved by manually placing its solid 3D model, found in the applicator library of the TPS. The Iterative Closest Point and the Coherent Point Drift algorithms were used, initialized with four known points, to register both EMT and CT scan reference frames using corresponding points from the EMT and CT based reconstructions of the phantom, following three approaches: one gynecological applicator, four interstitial catheters inside four calibration plates having an S-shaped path, and four 5 mm diameter ceramic marbles found in each of the four calibration plates. Once registered, the registration error (perpendicular distance) was computed. RESULTS The absolute median deviation from the expected value for EMT measurements in the disturbance free environment, CT-on-rails brachytherapy suite, and MRI-brachytherapy suite are 0.41, 0.23, and 0.31 mm, respectively, while for the CT scan it is 0.18 mm. These values significantly lie below the sensor's expected accuracy of 0.70 mm (p < 0.001), suggesting that the environment did not have a significant impact on the measurements, given that care is taken in the immediate surroundings. In all three environments, the two acquisitions and three registration approaches have mean and median registration errors that lie at or below 1 mm, which is lower than the clinical acceptable threshold of 2 mm. CONCLUSIONS The novel phantom allowed to successfully evaluate the accuracy of EMT-based reconstructions of catheters and a GYN tandem and ring applicator in different clinical environments. A registration method based only on the applicator geometry, reconstructed withan EMT sensor and the TPS solid applicator library, was validated and shows clinically acceptable accuracy, comparable to CT-based reconstruction but within a few minutes. Since the applicator is also visible in MRI, this method could potentially be used in clinics in an EMT-MR interstitial GYN brachytherapy workflow.
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Affiliation(s)
- Isaac Neri Gomez-Sarmiento
- Département de physique, de génie physique et d'optique, et Centre de recherche sur le cancer, Université Laval, Québec, Québec, Canada
- Service de physique médicale et de radioprotection, Centre Intégré de Cancérologie, CHU de Québec - Université Laval et Centre de recherche du CHU de Québec, Québec, Québec, Canada
| | - Daline Tho
- Division of Radiation Oncology, Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Christopher Dürrbeck
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), Erlangen, Germany
| | - Wim de Jager
- Elekta Brachytherapy, Veenendaal, The Netherlands
| | - Denis Laurendeau
- Département de génie électrique et de génie informatique, Faculté de sciences et de génie, Université Laval, Québec, Québec, Canada
| | - Luc Beaulieu
- Département de physique, de génie physique et d'optique, et Centre de recherche sur le cancer, Université Laval, Québec, Québec, Canada
- Service de physique médicale et de radioprotection, Centre Intégré de Cancérologie, CHU de Québec - Université Laval et Centre de recherche du CHU de Québec, Québec, Québec, Canada
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Sun M, Rao L, Zhang C, Zhang P, Chai G. Analysis of influence of surgical instruments on accuracy of magnetic navigation system for craniofacial surgery robots. Comput Assist Surg (Abingdon) 2023; 28:2210744. [PMID: 37256777 DOI: 10.1080/24699322.2023.2210744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023] Open
Abstract
IntroductionIn craniofacial surgery, magnetic navigation systems can effectively extend the doctor's limited visual range, improve their surgical precision, shorten the operation time, and reduce the incidence of surgical complications. Owing to the ease of magnetic navigation, the accuracy of the magnetic navigation system is affected by various equipment in the operating room. Therefore, its large-scale application is lacking because the navigation accuracy requirement can be extremely high during craniofacial surgery. Therefore, the accuracy of magnetic navigation systems is crucial. Various surgical instruments have been evaluated to effectively reduce the interference of magnetic navigation systems with surgical instruments. In craniofacial surgery, magnetic navigation systems can effectively extend the doctor's limited visual range, improve their surgical precision, shorten the operation time, and reduce the incidence of surgical complications. Owing to the ease of magnetic navigation, the accuracy of the magnetic navigation system is affected by various equipment in the operating room. Therefore, its large-scale application is lacking because the navigation accuracy requirement can be extremely high during craniofacial surgery. Therefore, the accuracy of magnetic navigation systems is crucial. Various surgical instruments have been evaluated to effectively reduce the interference of magnetic navigation systems with surgical instruments. In the surgical environment, the use of surgical instruments during mandibular surgery was simulated by selecting several conventional surgical instruments to record errors in the magnetic navigation system. The fluctuation values of the magnetic navigation errors were subsequently estimated and changes in its accuracy measured. MATLAB was used to calculate and analyze the fluctuations of the magnetic navigation errors. As results, the high-frequency electrosurgical system caused the greatest interference with the magnetic navigation system during surgery while powered on, with a maximum fluctuation error value of 1.8120 mm, and the maximum fluctuation error values of the stitch scissors, teeth forceps, and a needle holder were 1.3662, 1.3781, and 0.3912 mm, respectively. The closer the instrument is to the magnetic field generator or navigation target, the greater its impact. In conclusion, stitch scissors, teeth forceps, a needle holder, and the high-frequency electrosurgical system all affect magnetic navigation system accuracy. Therefore, it is necessary to avoid magnetic navigation system use and surgical instrument disturbances during surgery or select surgical instruments that do not interfere with the system. Surgical instruments must be evaluated for electromagnetic interference before they can be used in surgery with a magnetic navigation system.
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Affiliation(s)
- Mengzhe Sun
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Lan Rao
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, China
| | - Cunliang Zhang
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, China
| | - Peiming Zhang
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, China
- NMPA Key Laboratory for Respiratory and Anaesthetic Equipment, Shanghai, China
| | - Gang Chai
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Baker C, Xochicale M, Lin FY, Mathews S, Joubert F, Shakir DI, Miles R, Mosse CA, Zhao T, Liang W, Kunpalin Y, Dromey B, Mistry T, Sebire NJ, Zhang E, Ourselin S, Beard PC, David AL, Desjardins AE, Vercauteren T, Xia W. Intraoperative Needle Tip Tracking with an Integrated Fibre-Optic Ultrasound Sensor. SENSORS (BASEL, SWITZERLAND) 2022; 22:9035. [PMID: 36501738 PMCID: PMC9739176 DOI: 10.3390/s22239035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/15/2022] [Accepted: 11/16/2022] [Indexed: 06/17/2023]
Abstract
Ultrasound is an essential tool for guidance of many minimally-invasive surgical and interventional procedures, where accurate placement of the interventional device is critical to avoid adverse events. Needle insertion procedures for anaesthesia, fetal medicine and tumour biopsy are commonly ultrasound-guided, and misplacement of the needle may lead to complications such as nerve damage, organ injury or pregnancy loss. Clear visibility of the needle tip is therefore critical, but visibility is often precluded by tissue heterogeneities or specular reflections from the needle shaft. This paper presents the in vitro and ex vivo accuracy of a new, real-time, ultrasound needle tip tracking system for guidance of fetal interventions. A fibre-optic, Fabry-Pérot interferometer hydrophone is integrated into an intraoperative needle and used to localise the needle tip within a handheld ultrasound field. While previous, related work has been based on research ultrasound systems with bespoke transmission sequences, the new system-developed under the ISO 13485 Medical Devices quality standard-operates as an adjunct to a commercial ultrasound imaging system and therefore provides the image quality expected in the clinic, superimposing a cross-hair onto the ultrasound image at the needle tip position. Tracking accuracy was determined by translating the needle tip to 356 known positions in the ultrasound field of view in a tank of water, and by comparison to manual labelling of the the position of the needle in B-mode US images during an insertion into an ex vivo phantom. In water, the mean distance between tracked and true positions was 0.7 ± 0.4 mm with a mean repeatability of 0.3 ± 0.2 mm. In the tissue phantom, the mean distance between tracked and labelled positions was 1.1 ± 0.7 mm. Tracking performance was found to be independent of needle angle. The study demonstrates the performance and clinical compatibility of ultrasound needle tracking, an essential step towards a first-in-human study.
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Affiliation(s)
- Christian Baker
- School of Biomedical Engineering and Imaging Sciences, King’s College London, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
| | - Miguel Xochicale
- School of Biomedical Engineering and Imaging Sciences, King’s College London, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
| | - Fang-Yu Lin
- School of Biomedical Engineering and Imaging Sciences, King’s College London, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
| | - Sunish Mathews
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, UK
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London W1W 7TY, UK
| | - Francois Joubert
- School of Biomedical Engineering and Imaging Sciences, King’s College London, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
| | - Dzhoshkun I. Shakir
- School of Biomedical Engineering and Imaging Sciences, King’s College London, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
| | - Richard Miles
- School of Biomedical Engineering and Imaging Sciences, King’s College London, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
| | - Charles A. Mosse
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, UK
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London W1W 7TY, UK
| | - Tianrui Zhao
- School of Biomedical Engineering and Imaging Sciences, King’s College London, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
| | - Weidong Liang
- School of Biomedical Engineering and Imaging Sciences, King’s College London, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
| | - Yada Kunpalin
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London W1W 7TY, UK
- Elizabeth Garrett Anderson Institute for Women’s Health, University College London, 74 Huntley Street, London WC1E 6AU, UK
| | - Brian Dromey
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London W1W 7TY, UK
- Elizabeth Garrett Anderson Institute for Women’s Health, University College London, 74 Huntley Street, London WC1E 6AU, UK
| | - Talisa Mistry
- NIHR Great Ormond Street BRC and Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
| | - Neil J. Sebire
- NIHR Great Ormond Street BRC and Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
| | - Edward Zhang
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, UK
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London W1W 7TY, UK
| | - Sebastien Ourselin
- School of Biomedical Engineering and Imaging Sciences, King’s College London, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
| | - Paul C. Beard
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, UK
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London W1W 7TY, UK
| | - Anna L. David
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London W1W 7TY, UK
- Elizabeth Garrett Anderson Institute for Women’s Health, University College London, 74 Huntley Street, London WC1E 6AU, UK
| | - Adrien E. Desjardins
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, UK
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London W1W 7TY, UK
| | - Tom Vercauteren
- School of Biomedical Engineering and Imaging Sciences, King’s College London, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
| | - Wenfeng Xia
- School of Biomedical Engineering and Imaging Sciences, King’s College London, 4th Floor, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK
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Shi M, Bodian S, West SJ, Sathasivam S, Gordon RJ, Collier P, Vercauteren T, Desjardins AE, Noimark S, Xia W. Enhanced Photoacoustic Visualisation of Clinical Needles by Combining Interstitial and Extracorporeal Illumination of Elastomeric Nanocomposite Coatings. SENSORS (BASEL, SWITZERLAND) 2022; 22:6417. [PMID: 36080876 PMCID: PMC9460224 DOI: 10.3390/s22176417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/18/2022] [Accepted: 08/23/2022] [Indexed: 06/15/2023]
Abstract
Ultrasound (US) image guidance is widely used for minimally invasive procedures, but the invasive medical devices (such as metallic needles), especially their tips, can be poorly visualised in US images, leading to significant complications. Photoacoustic (PA) imaging is promising for visualising invasive devices and peripheral tissue targets. Light-emitting diodes (LEDs) acting as PA excitation sources facilitate the clinical translation of PA imaging, but the image quality is degraded due to the low pulse energy leading to insufficient contrast with needles at deep locations. In this paper, photoacoustic visualisation of clinical needles was enhanced by elastomeric nanocomposite coatings with superficial and interstitial illumination. Candle soot nanoparticle-polydimethylsiloxane (CSNP-PDMS) composites with high optical absorption and large thermal expansion coefficients were applied onto the needle exterior and the end-face of an optical fibre placed in the needle lumen. The excitation light was delivered at the surface by LED arrays and through the embedded optical fibre by a pulsed diode laser to improve the visibility of the needle tip. The performance was validated using an ex-vivo tissue model. An LED-based PA/US imaging system was used for imaging the needle out-of-plane and in-plane insertions over approach angles of 20 deg to 55 deg. The CSNP-PDMS composite conferred substantial visual enhancements on both the needle shaft and the tip, with an average of 1.7- and 1.6-fold improvements in signal-to-noise ratios (SNRs), respectively. With the extended light field involving extracorporeal and interstitial illumination and the highly absorbing coatings, enhanced visualisation of the needle shaft and needle tip was achieved with PA imaging, which could be helpful in current US-guided minimally invasive surgeries.
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Affiliation(s)
- Mengjie Shi
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, UK
| | - Semyon Bodian
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London W1W 7TY, UK
| | - Simeon J. West
- Department of Anaesthesia, University College Hospital, London NW1 2BU, UK
| | - Sanjayan Sathasivam
- Department of Chemistry, University College London, London WC1H 0AJ, UK or
- School of Engineering, London South Bank University, London SE1 0AA, UK
| | | | - Paul Collier
- Johnson Matthey Technology Centre, Reading RG4 9NH, UK
| | - Tom Vercauteren
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, UK
| | - Adrien E. Desjardins
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London W1W 7TY, UK
| | - Sacha Noimark
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London W1W 7TY, UK
| | - Wenfeng Xia
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, UK
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Rabbani N, Calvet L, Espinel Y, Le Roy B, Ribeiro M, Buc E, Bartoli A. A methodology and clinical dataset with ground-truth to evaluate registration accuracy quantitatively in computer-assisted Laparoscopic Liver Resection. COMPUTER METHODS IN BIOMECHANICS AND BIOMEDICAL ENGINEERING: IMAGING & VISUALIZATION 2021. [DOI: 10.1080/21681163.2021.1997642] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- N. Rabbani
- EnCoV, Institut Pascal, Clermont-Ferrand, France
| | - L. Calvet
- EnCoV, Institut Pascal, Clermont-Ferrand, France
- CHU, Clermont-Ferrand, France
- IRIT, University of Toulouse
| | - Y. Espinel
- EnCoV, Institut Pascal, Clermont-Ferrand, France
| | - B. Le Roy
- EnCoV, Institut Pascal, Clermont-Ferrand, France
- CHU, Saint-Etienne, France
| | - M. Ribeiro
- EnCoV, Institut Pascal, Clermont-Ferrand, France
- CHU, Clermont-Ferrand, France
| | - E. Buc
- EnCoV, Institut Pascal, Clermont-Ferrand, France
- CHU, Clermont-Ferrand, France
| | - A. Bartoli
- EnCoV, Institut Pascal, Clermont-Ferrand, France
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Pérez-Pachón L, Poyade M, Lowe T, Gröning F. Image Overlay Surgery Based on Augmented Reality: A Systematic Review. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1260:175-195. [PMID: 33211313 DOI: 10.1007/978-3-030-47483-6_10] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Augmented Reality (AR) applied to surgical guidance is gaining relevance in clinical practice. AR-based image overlay surgery (i.e. the accurate overlay of patient-specific virtual images onto the body surface) helps surgeons to transfer image data produced during the planning of the surgery (e.g. the correct resection margins of tissue flaps) to the operating room, thus increasing accuracy and reducing surgery times. We systematically reviewed 76 studies published between 2004 and August 2018 to explore which existing tracking and registration methods and technologies allow healthcare professionals and researchers to develop and implement these systems in-house. Most studies used non-invasive markers to automatically track a patient's position, as well as customised algorithms, tracking libraries or software development kits (SDKs) to compute the registration between patient-specific 3D models and the patient's body surface. Few studies combined the use of holographic headsets, SDKs and user-friendly game engines, and described portable and wearable systems that combine tracking, registration, hands-free navigation and direct visibility of the surgical site. Most accuracy tests included a low number of subjects and/or measurements and did not normally explore how these systems affect surgery times and success rates. We highlight the need for more procedure-specific experiments with a sufficient number of subjects and measurements and including data about surgical outcomes and patients' recovery. Validation of systems combining the use of holographic headsets, SDKs and game engines is especially interesting as this approach facilitates an easy development of mobile AR applications and thus the implementation of AR-based image overlay surgery in clinical practice.
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Affiliation(s)
- Laura Pérez-Pachón
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK.
| | - Matthieu Poyade
- School of Simulation and Visualisation, Glasgow School of Art, Glasgow, UK
| | - Terry Lowe
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
- Head and Neck Oncology Unit, Aberdeen Royal Infirmary (NHS Grampian), Aberdeen, UK
| | - Flora Gröning
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
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Sorriento A, Porfido MB, Mazzoleni S, Calvosa G, Tenucci M, Ciuti G, Dario P. Optical and Electromagnetic Tracking Systems for Biomedical Applications: A Critical Review on Potentialities and Limitations. IEEE Rev Biomed Eng 2019; 13:212-232. [PMID: 31484133 DOI: 10.1109/rbme.2019.2939091] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Optical and electromagnetic tracking systems represent the two main technologies integrated into commercially-available surgical navigators for computer-assisted image-guided surgery so far. Optical Tracking Systems (OTSs) work within the optical spectrum to track the position and orientation, i.e., pose of target surgical instruments. OTSs are characterized by high accuracy and robustness to environmental conditions. The main limitation of OTSs is the need of a direct line-of-sight between the optical markers and the camera sensor, rigidly fixed into the operating theatre. Electromagnetic Tracking Systems (EMTSs) use electromagnetic field generator to detect the pose of electromagnetic sensors. EMTSs do not require such a direct line-of-sight, however the presence of metal or ferromagnetic sources in the operating workspace can significantly affect the measurement accuracy. The aim of the proposed review is to provide a complete and detailed overview of optical and electromagnetic tracking systems, including working principles, source of error and validation protocols. Moreover, commercial and research-oriented solutions, as well as clinical applications, are described for both technologies. Finally, a critical comparative analysis of the state of the art which highlights the potentialities and the limitations of each tracking system for a medical use is provided.
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Attivissimo F, Lanzolla AML, Carlone S, Larizza P, Brunetti G. A novel electromagnetic tracking system for surgery navigation. Comput Assist Surg (Abingdon) 2019; 23:42-52. [PMID: 30497291 DOI: 10.1080/24699322.2018.1529199] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
OBJECTIVE This paper proposes the development of a novel electromagnetic tracking system for navigation surgery. Main objective is to provide a system able to operate in a wide tracking volume to make easier and efficient the surgical procedures by assuring high measurement accuracy. METHODS A new field generator consisting in five transmitting coils excited with Frequency Division Multiplexing technique has been developed. Attention is devoted to designing and arrangement of the coils to assure high sensitivity, system scalability and a homogeneous magnetic field inside working volume. A suitable technique based on Look-Up-Table is applied for sensor position calculation and an anthropomorphic robot is used for table calibration. RESULTS Experimental tests highlight a good repeatability of the measurement data and a negligible noise influence for the proposed system. The obtained tracking volume is wider with respect to the commercial tracking device used in surgical applications and seem promising. CONCLUSION The main characteristic of the developed system consists of: scalable and modular configuration of Field Generator, high measured sensitivity due to the increased number of transmitting coils with respect to the classical configuration and large tracking volume. The development of the proposed magnetic tracking systems with high accuracy and wide working volume allows to promote broader utilization of advantaged techniques in surgery procedures for both improving the effectiveness and decreasing the invasiveness of medical interventions.
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Affiliation(s)
- Filippo Attivissimo
- a Department of Electrical and Information Engineering , Polytechnic University of Bari , Bari , Italy
| | - Anna Maria Lucia Lanzolla
- a Department of Electrical and Information Engineering , Polytechnic University of Bari , Bari , Italy
| | - Sabatina Carlone
- a Department of Electrical and Information Engineering , Polytechnic University of Bari , Bari , Italy
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Abstract
Ultrasound image guidance is widely used in minimally invasive procedures, including fetal surgery. In this context, maintaining visibility of medical devices is a significant challenge. Needles and catheters can readily deviate from the ultrasound imaging plane as they are inserted. When the medical device tips are not visible, they can damage critical structures, with potentially profound consequences including loss of pregnancy. In this study, we performed 3D ultrasonic tracking of a needle using a novel probe with a 1.5D array of transducer elements that was driven by a commercial ultrasound system. A fiber-optic hydrophone integrated into the needle received transmissions from the probe, and data from this sensor was processed to estimate the position of the hydrophone tip in the coordinate space of the probe. Golay coding was used to increase the signal-to-noise (SNR). The relative tracking accuracy was better than 0.4 mm in all dimensions, as evaluated using a water phantom. To obtain a preliminary indication of the clinical potential of 3D ultrasonic needle tracking, an intravascular needle insertion was performed in an in vivo pregnant sheep model. The SNR values ranged from 12 to 16 at depths of 20 to 31 mm and at an insertion angle of 49° relative to the probe surface normal. The results of this study demonstrate that 3D ultrasonic needle tracking with a fiber-optic hydrophone sensor and a 1.5D array is feasible in clinically realistic environments.
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Multi-Operational Selective Computer-Assisted Targeting of hepatocellular carcinoma-Evaluation of a novel approach for navigated tumor ablation. PLoS One 2018; 13:e0197914. [PMID: 29791518 PMCID: PMC5965844 DOI: 10.1371/journal.pone.0197914] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 05/10/2018] [Indexed: 02/07/2023] Open
Abstract
Objective To facilitate precise local ablation of hepatocellular carcinoma (HCC) in a setting of combined ablation and transarterial chemoembolization (TACE), we evaluated accuracy and efficiency of a novel technique for navigated positioning of ablation probes using intrahepatic tumor referencing and electromagnetic (EM) guidance, in a porcine model. Methods An angiographic wire with integrated EM reference sensor at its tip was inserted via a transarterial femoral access and positioned in the vicinity of artificial liver tumors. The resulting offset distance between the tumor center and the intrahepatic endovascular EM reference was calculated. Subsequently, EM tracked ablation probes were inserted percutaneously and navigated toward the tumor center, relying on continuous EM guidance via the intrahepatic reference. Targeting accuracy was assessed as the Euclidean distance between the tip of the ablation probe and the tumor center (Target Positioning Error, TPE). Procedural efficiency was assessed as time efforts for tumor referencing and tumor targeting. Results In 6 animals, 124 targeting measurements were performed with an offset distance < 30 mm (clinically most feasible position), resulting in a mean TPE of 2.9 ± 1.6 mm. No significant correlation between the TPE and different intrahepatic offset distances (range 21 to 61 mm, n = 365) was shown as long as the EM reference was placed within the liver. However, the mean TPE increased when placing the EM reference externally on the animal skin (p < 0.01). TPE was similar when targeting under continuous ventilation or in apnea (p = 0.50). Mean time for tumor referencing and navigated targeting was 6.5 ± 3.8 minutes and 14 ± 8 seconds, respectively. Conclusion The proposed technique allows precise and efficient navigated positioning of ablation probes into liver tumors in the animal model. We introduce a simple approach suitable for combined ablation and TACE of HCC in a single treatment session.
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Abstract
Ultrasound is well suited for guiding many minimally invasive procedures, but its use is often precluded by the poor visibility of medical devices. When devices are not visible, they can damage critical structures, with life-threatening complications. Here, we developed the first ultrasound probe that comprises both focused and unfocused transducer elements to provide both 2D B-mode ultrasound imaging and 3D ultrasonic needle tracking. A fibre-optic hydrophone was integrated into a needle to receive Golay-coded transmissions from the probe and these data were processed to obtain tracking images of the needle tip. The measured tracking accuracy in water was better than 0.4 mm in all dimensions. To demonstrate the clinical potential of this system, insertions were performed into the spine and the uterine cavity, in swine and pregnant ovine models in vivo. In both models, the SNR ranged from 13 to 38 at depths of 22 to 38 mm, at out-of-plane distances of 1 to 15 mm, and at insertion angles of 33 to 42 degrees relative to the probe surface normal. This novel ultrasound imaging/tracking probe has strong potential to improve procedural outcomes by providing 3D needle tip locations that are co-registered to ultrasound images, while maintaining compatibility with current clinical workflow.
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Ultrasound-navigated radiofrequency ablation of thyroid nodules with integrated electromagnetic tracking: comparison with conventional ultrasound guidance in gelatin models. Int J Comput Assist Radiol Surg 2017; 12:1635-1642. [PMID: 28271358 DOI: 10.1007/s11548-017-1544-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 02/20/2017] [Indexed: 01/29/2023]
Abstract
PURPOSE A thyroid-like gelatin model was used to determine potential superiority of a new navigation system for ultrasound (US)-guided electrode insertion called EchoTrack, featuring a US probe with an integrated electromagnetic field generator, in comparison with conventional US when performing radiofrequency ablation. METHODS In order to compare 20 navigated ablations with 20 ablations under conventional US guidance, a thyroid-like gelatin model was used. In each group, 10 in-plane and 10 out-of-plane punctures were performed. Metal seeds measuring 8.5 [Formula: see text] 1.8 mm served as ablation targets. The number of redirections until final electrode placement, targeting accuracy and electrode placement time were measured. RESULTS The number of redirections could be significantly ([Formula: see text]) reduced from 2.7 ± 1.3 in the conventional group to 0.2 ± 0.5 in the EchoTrack group. Accuracy increased from 3.9 ± 4.7 to 2.0 ± 1.9 mm. The total placement time increased from 39 ± 20.5 to 79.2 ± 26 s. CONCLUSIONS EchoTrack is able to reduce the redirections needed to place the electrode in comparison with conventional US and provides high placement accuracy. Our new navigation system has high potential to reduce the risk of harming critical structures and to improve guidance during ablation of difficult nodules, as treatment planning as well as the safety of out-of-plane punctures are improved.
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Li M, Hansen C, Rose G. A software solution to dynamically reduce metallic distortions of electromagnetic tracking systems for image-guided surgery. Int J Comput Assist Radiol Surg 2017; 12:1621-1633. [PMID: 28258402 DOI: 10.1007/s11548-017-1546-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 02/21/2017] [Indexed: 11/30/2022]
Abstract
PURPOSE Electromagnetic tracking systems (EMTS) have achieved a high level of acceptance in clinical settings, e.g., to support tracking of medical instruments in image-guided interventions. However, tracking errors caused by movable metallic medical instruments and electronic devices are a critical problem which prevents the wider application of EMTS for clinical applications. METHODS We plan to introduce a method to dynamically reduce tracking errors caused by metallic objects in proximity to the magnetic sensor coil of the EMTS. We propose a method using ramp waveform excitation based on modeling the conductive distorter as a resistance-inductance circuit. Additionally, a fast data acquisition method is presented to speed up the refresh rate. RESULTS With the current approach, the sensor's positioning mean error is estimated to be 3.4, 1.3 and 0.7 mm, corresponding to a distance between the sensor and center of the transmitter coils' array of up to 200, 150 and 100 mm, respectively. The sensor pose error caused by different medical instruments placed in proximity was reduced by the proposed method to a level lower than 0.5 mm in position and [Formula: see text] in orientation. By applying the newly developed fast data acquisition method, we achieved a system refresh rate up to approximately 12.7 frames per second. CONCLUSIONS Our software-based approach can be integrated into existing medical EMTS seamlessly with no change in hardware. It improves the tracking accuracy of clinical EMTS when there is a metallic object placed near the sensor coil and has the potential to improve the safety and outcome of image-guided interventions.
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Affiliation(s)
- Mengfei Li
- Chair for Medical Telematics and Medical Technology, Institute of Medical Technology, Otto-von Guericke Universität Magdeburg, G09-324, Universitätsplatz 2, 39016, Magdeburg, Germany. .,Research Group of Computer-Assisted Surgery, Institute of Simulation and Graphics, Otto-von-Guericke Universität Magdeburg, G29-209, Universitätsplatz 2, 39016, Magdeburg, Germany.
| | - Christian Hansen
- Research Group of Computer-Assisted Surgery, Institute of Simulation and Graphics, Otto-von-Guericke Universität Magdeburg, G29-209, Universitätsplatz 2, 39016, Magdeburg, Germany
| | - Georg Rose
- Chair for Medical Telematics and Medical Technology, Institute of Medical Technology, Otto-von Guericke Universität Magdeburg, G09-324, Universitätsplatz 2, 39016, Magdeburg, Germany
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Xia W, Ginsberg Y, West SJ, Nikitichev DI, Ourselin S, David AL, Desjardins AE. Coded excitation ultrasonic needle tracking: An in vivo study. Med Phys 2016; 43:4065. [PMID: 27370125 PMCID: PMC5207306 DOI: 10.1118/1.4953205] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 04/25/2016] [Accepted: 05/21/2016] [Indexed: 01/22/2023] Open
Abstract
PURPOSE Accurate and efficient guidance of medical devices to procedural targets lies at the heart of interventional procedures. Ultrasound imaging is commonly used for device guidance, but determining the location of the device tip can be challenging. Various methods have been proposed to track medical devices during ultrasound-guided procedures, but widespread clinical adoption has remained elusive. With ultrasonic tracking, the location of a medical device is determined by ultrasonic communication between the ultrasound imaging probe and a transducer integrated into the medical device. The signal-to-noise ratio (SNR) of the transducer data is an important determinant of the depth in tissue at which tracking can be performed. In this paper, the authors present a new generation of ultrasonic tracking in which coded excitation is used to improve the SNR without spatial averaging. METHODS A fiber optic hydrophone was integrated into the cannula of a 20 gauge insertion needle. This transducer received transmissions from the ultrasound imaging probe, and the data were processed to obtain a tracking image of the needle tip. Excitation using Barker or Golay codes was performed to improve the SNR, and conventional bipolar excitation was performed for comparison. The performance of the coded excitation ultrasonic tracking system was evaluated in an in vivo ovine model with insertions to the brachial plexus and the uterine cavity. RESULTS Coded excitation significantly increased the SNRs of the tracking images, as compared with bipolar excitation. During an insertion to the brachial plexus, the SNR was increased by factors of 3.5 for Barker coding and 7.1 for Golay coding. During insertions into the uterine cavity, these factors ranged from 2.9 to 4.2 for Barker coding and 5.4 to 8.5 for Golay coding. The maximum SNR was 670, which was obtained with Golay coding during needle withdrawal from the brachial plexus. Range sidelobe artifacts were observed in tracking images obtained with Barker coded excitation, and they were visually absent with Golay coded excitation. The spatial tracking accuracy was unaffected by coded excitation. CONCLUSIONS Coded excitation is a viable method for improving the SNR in ultrasonic tracking without compromising spatial accuracy. This method provided SNR increases that are consistent with theoretical expectations, even in the presence of physiological motion. With the ultrasonic tracking system in this study, the SNR increases will have direct clinical implications in a broad range of interventional procedures by improving visibility of medical devices at large depths.
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Affiliation(s)
- Wenfeng Xia
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Yuval Ginsberg
- Institute for Women’s Health, University College London, 86-96 Chenies Mews, London WC1E 6HX, United Kingdom
| | - Simeon J. West
- Department of Anaesthesia, University College Hospital, Main Theaters, Maple Bridge Link Corridor, Podium 3, 235 Euston Road, London NW1 2BU, United Kingdom
| | - Daniil I. Nikitichev
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Sebastien Ourselin
- Center for Medical Imaging Computing, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Anna L. David
- Institute for Women’s Health, University College London, 86-96 Chenies Mews, London WC1E 6HX, United Kingdom
| | - Adrien E. Desjardins
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
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Xia W, Mari JM, West SJ. In-plane ultrasonic needle tracking using a fiber-optic hydrophone. Med Phys 2015; 42:5983-91. [PMID: 26429273 PMCID: PMC5207301 DOI: 10.1118/1.4931418] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 09/01/2015] [Accepted: 09/03/2015] [Indexed: 12/26/2022] Open
Abstract
PURPOSE Accurate and efficient guidance of needles to procedural targets is critically important during percutaneous interventional procedures. Ultrasound imaging is widely used for real-time image guidance in a variety of clinical contexts, but with this modality, uncertainties about the location of the needle tip within the image plane lead to significant complications. Whilst several methods have been proposed to improve the visibility of the needle, achieving accuracy and compatibility with current clinical practice is an ongoing challenge. In this paper, the authors present a method for directly visualizing the needle tip using an integrated fiber-optic ultrasound receiver in conjunction with the imaging probe used to acquire B-mode ultrasound images. METHODS Needle visualization and ultrasound imaging were performed with a clinical ultrasound imaging system. A miniature fiber-optic ultrasound hydrophone was integrated into a 20 gauge injection needle tip to receive transmissions from individual transducer elements of the ultrasound imaging probe. The received signals were reconstructed to create an image of the needle tip. Ultrasound B-mode imaging was interleaved with needle tip imaging. A first set of measurements was acquired in water and tissue ex vivo with a wide range of insertion angles (15°-68°) to study the accuracy and sensitivity of the tracking method. A second set was acquired in an in vivo swine model, with needle insertions to the brachial plexus. A third set was acquired in an in vivo ovine model for fetal interventions, with insertions to different locations within the uterine cavity. Two linear ultrasound imaging probes were used: a 14-5 MHz probe for the first and second sets, and a 9-4 MHz probe for the third. RESULTS During insertions in tissue ex vivo and in vivo, the imaged needle tip had submillimeter axial and lateral dimensions. The signal-to-noise (SNR) of the needle tip was found to depend on the insertion angle. With the needle tip in water, the SNR of the needle tip varied with insertion angle, attaining values of 284 at 27° and 501 at 68°. In swine tissue ex vivo, the SNR decreased from 80 at 15° to 16 at 61°. In swine tissue in vivo, the SNR varied with depth, from 200 at 17.5 mm to 48 at 26 mm, with a constant insertion angle of 40°. In ovine tissue in vivo, within the uterine cavity, the SNR varied from 46.4 at 25 mm depth to 18.4 at 32 mm depth, with insertion angles in the range of 26°-65°. CONCLUSIONS A fiber-optic ultrasound receiver integrated into the needle cannula in combination with single-element transmissions from the imaging probe allows for direct visualization of the needle tip within the ultrasound imaging plane. Visualization of the needle tip was achieved at depths and insertion angles that are encountered during nerve blocks and fetal interventions. The method presented in this paper has strong potential to improve the safety and efficiency of ultrasound-guided needle insertions.
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Affiliation(s)
- Wenfeng Xia
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Jean Martial Mari
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom and GePaSud, University of French Polynesia, Faa’a 98702, French Polynesia
| | - Simeon J. West
- Department of Anaesthesia, University College Hospital, Main Theatres, Maple Bridge Link Corridor, Podium 3, 235 Euston Road, London NW1 2BU, United Kingdom
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Electromagnetic tracking in surgical and interventional environments: usability study. Int J Comput Assist Radiol Surg 2014; 10:253-62. [PMID: 25193146 DOI: 10.1007/s11548-014-1110-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 08/10/2014] [Indexed: 12/13/2022]
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Franz AM, Haidegger T, Birkfellner W, Cleary K, Peters TM, Maier-Hein L. Electromagnetic tracking in medicine--a review of technology, validation, and applications. IEEE TRANSACTIONS ON MEDICAL IMAGING 2014; 33:1702-1725. [PMID: 24816547 DOI: 10.1109/tmi.2014.2321777] [Citation(s) in RCA: 190] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Object tracking is a key enabling technology in the context of computer-assisted medical interventions. Allowing the continuous localization of medical instruments and patient anatomy, it is a prerequisite for providing instrument guidance to subsurface anatomical structures. The only widely used technique that enables real-time tracking of small objects without line-of-sight restrictions is electromagnetic (EM) tracking. While EM tracking has been the subject of many research efforts, clinical applications have been slow to emerge. The aim of this review paper is therefore to provide insight into the future potential and limitations of EM tracking for medical use. We describe the basic working principles of EM tracking systems, list the main sources of error, and summarize the published studies on tracking accuracy, precision and robustness along with the corresponding validation protocols proposed. State-of-the-art approaches to error compensation are also reviewed in depth. Finally, an overview of the clinical applications addressed with EM tracking is given. Throughout the paper, we report not only on scientific progress, but also provide a review on commercial systems. Given the continuous debate on the applicability of EM tracking in medicine, this paper provides a timely overview of the state-of-the-art in the field.
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Interventional real-time ultrasound imaging with an integrated electromagnetic field generator. Int J Comput Assist Radiol Surg 2014; 9:759-68. [DOI: 10.1007/s11548-014-0990-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 03/06/2014] [Indexed: 11/26/2022]
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Bien T, Li M, Salah Z, Rose G. Electromagnetic tracking system with reduced distortion using quadratic excitation. Int J Comput Assist Radiol Surg 2013; 9:323-32. [PMID: 23918006 PMCID: PMC3955490 DOI: 10.1007/s11548-013-0925-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Accepted: 07/04/2013] [Indexed: 10/29/2022]
Abstract
PURPOSE Electromagnetic tracking systems, frequently used in minimally invasive surgery, are affected by conductive distorters. The influence of conductive distorters on electromagnetic tracking system accuracy can be reduced through magnetic field modifications. This approach was developed and tested. METHODS The voltage induced directly by the emitting coil in the sensing coil without additional influence by the conductive distorter depends on the first derivative of the voltage on the emitting coil. The voltage which is induced indirectly by the emitting coil across the conductive distorter in the sensing coil, however, depends on the second derivative of the voltage on the emitting coil. The electromagnetic tracking system takes advantage of this difference by supplying the emitting coil with a quadratic excitation voltage. The method is adaptive relative to the amount of distortion cause by the conductive distorters. This approach is evaluated with an experimental setup of the electromagnetic tracking system. RESULTS In vitro testing showed that the maximal error decreased from 10.9 to 3.8 mm when the quadratic voltage was used to excite the emitting coil instead of the sinusoidal voltage. Furthermore, the root mean square error in the proximity of the aluminum disk used as a conductive distorter was reduced from 3.5 to 1.6 mm when the electromagnetic tracking system used the quadratic instead of sinusoidal excitation. CONCLUSIONS Electromagnetic tracking with quadratic excitation is immune to the effects of a conductive distorter, especially compared with sinusoidal excitation of the emitting coil. Quadratic excitation of electromagnetic tracking for computer-assisted surgery is promising for clinical applications.
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Affiliation(s)
- Tomasz Bien
- Chair for Healthcare Telematics and Medical Engineering, Otto-von-Guericke University, Magdeburg, Germany,
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Haidegger T, Fenyvesi G, Sirokai B, Kelemen M, Nagy M, Takács B, Kovács L, Benyó B, Benyó Z. Towards unified electromagnetic tracking system assessment-static errors. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2012; 2011:1905-8. [PMID: 22254703 DOI: 10.1109/iembs.2011.6090539] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Recent advances in Image-Guided Surgery allows physicians to incorporate up-to-date, high quality patient data in the surgical decision making, and sometimes to directly perform operations based on pre- or intra-operatively acquired patient images. Electromagnetic tracking is the fastest growing area within, where the position and orientation of tiny sensors can be determined with sub-millimeter accuracy in the field created by a generator. One of the major barriers to the wider spread of electromagnetic tracking solutions is their susceptibility to ferromagnetic materials and external electromagnetic sources. The research community has long been engaged with the topic to find engineering solutions to increase measurement reliability and accuracy. This article gives an overview of related experiments, and presents our recommendation towards a robust method to collect representative data about electromagnetic trackers.
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Affiliation(s)
- Tamás Haidegger
- Dept of Control Engineering and Information Technology, Budapest University of Technology and Economics, Magyar tudósok krt 2, Budapest, Hungary.
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Yoo J, Schafer S, Uneri A, Otake Y, Khanna AJ, Siewerdsen JH. An electromagnetic “Tracker-in-Table” configuration for X-ray fluoroscopy and cone-beam CT-guided surgery. Int J Comput Assist Radiol Surg 2012; 8:1-13. [PMID: 22585463 DOI: 10.1007/s11548-012-0744-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Accepted: 04/26/2012] [Indexed: 11/25/2022]
Affiliation(s)
- J Yoo
- Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD, USA
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Seeberger R, Kane G, Hoffmann J, Eggers G. Accuracy assessment for navigated maxillo-facial surgery using an electromagnetic tracking device. J Craniomaxillofac Surg 2012; 40:156-61. [DOI: 10.1016/j.jcms.2011.03.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Revised: 01/13/2011] [Accepted: 03/01/2011] [Indexed: 11/15/2022] Open
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Abstract
The study proposes a rigid-body biomechanical model of the trunk and whole upper limb including scapula and the test of this model with a kinematic method using a six-dimensional (6-D) electromagnetic motion capture (mocap) device. Large unconstrained natural trunk-assisted reaching movements were recorded in 7 healthy subjects. The 3-D positions of anatomical landmarks were measured and then compared to their estimation given by the biomechanical chain fed with joint angles (the direct kinematics). Thus, the prediction errors was attributed to the different joints and to the different simplifications introduced in the model. Large (approx. 4 cm) end-point prediction errors at the level of the hand were reduced (to approx. 2 cm) if translations of the scapula were taken into account. As a whole, the 6-D mocap seems to give accurate results, except for pronosupination. The direct kinematic model could be used as a virtual mannequin for other applications, such as computer animation or clinical and ergonomical evaluations.
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Abstract
PURPOSE OF REVIEW Advances in the neurosurgical management of pituitary tumors have included the refinement of surgical access and significant progress in navigation technology to help further reduce morbidity and improve outcome. Similarly, stereotactic radiosurgery has evolved to become an integral part in pituitary tumors not amenable to medical or surgical treatment. RECENT FINDINGS The evolution of minimally invasive surgery has evolved toward endoscopic versus microscopic trans-sphenoidal approaches for pituitary tumors. Debate exists regarding each approach, with advocates for both championing their cause. Stereotactic and fractional radiosurgery have been shown to be a safe and effective means of controlling tumor growth and ensuring hormonal stabilization, with longer-term data available for GammaKnife compared with CyberKnife. SUMMARY The advances in trans-sphenoidal surgical approaches, navigation technological improvements and the current results of stereotactic radiosurgery are discussed.
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Abstract
Fluoronavigation is an image-guided technology which uses intra-operative fluoroscopic images taken under a real-time tracking system and registration to guide surgical procedures. With the skeleton and the instrument registered, guidance under an optical tracking system is possible, allowing fixation of the fracture and insertion of an implant. This technology helps to minimise exposure to x-rays, providing multiplanar views for monitoring and accurate positioning of implants. It allows real-time interactive quantitative data for decision-making and expands the application of minimally invasive surgery. In orthopaedic trauma its use can be further enhanced by combining newer imaging technologies such as intra-operative three-dimensional fluoroscopy and optical image guidance, new advances in software for fracture reduction, and new tracking mechanisms using electromagnetic technology. The major obstacles for general and wider applications are the inability to track individual fracture fragments, no navigated real-time fracture reduction, and the lack of an objective assessment method for cost-effectiveness. We believe that its application will go beyond the operating theatre and cover all aspects of patient management, from pre-operative planning to intra-operative guidance and postoperative rehabilitation.
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Affiliation(s)
- K. S. Leung
- Department of Orthopaedics & Traumatology, The Chinese University of Hong Kong, 5/F, Clinical Sciences Building, Prince of Wales Hospital, Shatin, Hong Kong
| | - N. Tang
- Department of Orthopaedics & Traumatology, The Chinese University of Hong Kong, 5/F, Clinical Sciences Building, Prince of Wales Hospital, Shatin, Hong Kong
| | - L. W. H. Cheung
- Department of Orthopaedics & Traumatology, The Chinese University of Hong Kong, 5/F, Clinical Sciences Building, Prince of Wales Hospital, Shatin, Hong Kong
| | - E. Ng
- Department of Orthopaedics & Traumatology, The Chinese University of Hong Kong, 5/F, Clinical Sciences Building, Prince of Wales Hospital, Shatin, Hong Kong
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Stevens F, Conditt MA, Kulkarni N, Ismaily SK, Noble PC, Lionberger DR. Minimizing electromagnetic interference from surgical instruments on electromagnetic surgical navigation. Clin Orthop Relat Res 2010; 468:2244-50. [PMID: 20512439 PMCID: PMC2895861 DOI: 10.1007/s11999-010-1366-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Accepted: 04/13/2010] [Indexed: 01/31/2023]
Abstract
BACKGROUND Electromagnetic computer-assisted surgery (EM-CAS) can be affected by various metallic or ferromagnetic factors. QUESTIONS/PURPOSES We determined to what extent metals interfere with accuracy and identified measures to prevent interference from occurring. METHODS Using an EM-CAS system, we made six standard measurements of tibiofemoral position and alignment on a surrogate knee. A stainless steel mallet was positioned 10 cm from the stylus, and then 10 cm from the localizer to create errors attributable to electromagnetic interference. The experiment was repeated with bars of different metals placed 10 cm from the stylus. RESULTS The maximum errors recorded with a mallet were: varus/valgus alignment, -2.7 degrees and 2.4 degrees; flexion/extension, -5.8 degrees and 3.0 degrees; lateral resection level, -3.1 and 7.5 mm; and medial resection level, -4.0 and 2.3 mm, respectively. The smallest errors were recorded with cylinders of titanium, cobalt-chrome alloy, and stainless steels. When moved more than 10 cm away from the stylus, errors became negligible. CONCLUSIONS The accuracy of EM navigation systems is affected substantially by the size, type, proximity, and shape of metal objects. CLINICAL RELEVANCE Stainless steel objects, such as cutting blocks and trial prostheses, should be kept more than 10 cm from EM-CAS instruments to minimize error.
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Affiliation(s)
| | - Michael A. Conditt
- Institute of Orthopedic Research and Education, 6550 Fannin St, Suite 2512, Houston, TX 77030 USA
| | - Nikhil Kulkarni
- Institute of Orthopedic Research and Education, 6550 Fannin St, Suite 2512, Houston, TX 77030 USA
| | - Sabir K. Ismaily
- Institute of Orthopedic Research and Education, 6550 Fannin St, Suite 2512, Houston, TX 77030 USA
| | - Philip C. Noble
- Baylor College of Medicine, Houston, TX USA
- Institute of Orthopedic Research and Education, 6550 Fannin St, Suite 2512, Houston, TX 77030 USA
| | - David R. Lionberger
- Baylor College of Medicine, Houston, TX USA
- Southwest Orthopedic Group, LLP, 6560 Fannin, Suite 1016, Houston, TX 77030 USA
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Widmann G, Stoffner R, Bale R. Errors and error management in image-guided craniomaxillofacial surgery. ACTA ACUST UNITED AC 2009; 107:701-15. [DOI: 10.1016/j.tripleo.2009.02.011] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2008] [Revised: 02/05/2009] [Accepted: 02/05/2009] [Indexed: 12/15/2022]
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Abdoli-Eramaki M, Stevenson JM, Agnew MJ, Kamalzadeh A. Comparison of 3D dynamic virtual model to link segment model for estimation of net L4/L5 reaction moments during lifting. Comput Methods Biomech Biomed Engin 2009. [DOI: 10.1080/10255840802434233] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Duong L, Mac-Thiong JM, Labelle H. Real time noninvasive assessment of external trunk geometry during surgical correction of adolescent idiopathic scoliosis. SCOLIOSIS 2009; 4:5. [PMID: 19239713 PMCID: PMC2651122 DOI: 10.1186/1748-7161-4-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Accepted: 02/24/2009] [Indexed: 12/02/2022]
Abstract
Background The correction of trunk deformity is crucial in scoliosis surgery, especially for the patient's self-image. However, direct visualization of external scoliotic trunk deformity during surgical correction is difficult due to the covering draping sheets. Methods An optoelectronic camera system with 10 passive markers is used to track the trunk geometry of 5 scoliotic patients during corrective surgery. The position of 10 anatomical landmarks and 5 trunk indices computed from the position of the passive markers are compared during and after instrumentation of the spine. Results Internal validation of the accuracy of tracking was evaluated at 0.41 +/- 0.05 mm RMS. Intra operative tracking during surgical maneuvers shows improvement of the shoulder balance during and after correction of the spine. Improvement of the overall patient balance is observed. At last, a minor increase of the spinal length can be noticed. Conclusion Tracking of the external geometry of the trunk during surgical correction is useful to monitor changes occurring under the sterile draping sheets. Moreover, this technique can used be used to reach the optimal configuration on the operating frame before proceeding to surgery. The current tracking technique was able to detect significant changes in trunk geometry caused by posterior instrumentation of the spine despite significant correction of the spinal curvature. It could therefore become relevant for computer-assisted guidance of surgical maneuvers when performing posterior instrumentation of the scoliotic spine, provide important insights during positioning of patients.
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Affiliation(s)
- Luc Duong
- Research Center, Hôpital Sainte-Justine, Montréal, Québec, Canada.
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Ren H, Kazanzides P. Hybrid attitude estimation for laparoscopic surgical tools: a preliminary study. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2009; 2009:5583-5586. [PMID: 19964132 DOI: 10.1109/iembs.2009.5333487] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Laparoscopic surgery poses a challenging problem for a real-time navigation system: how to keep tracking the surgical tools inside the human body intraoperatively. This paper proposes a sensor fusion method for a hybrid tracking system that incorporates a miniature inertial measurement unit and an electromagnetic navigation system, in order to obtain continuous orientation information, even in the presence of metal objects. The sensor fusion algorithm employs an extended Kalman filter to integrate the data from the two sensor streams, based on a quaternion formulation of the system dynamics. The preliminary experimental results show that the integration of low-cost inertial measurement is able to compensate the distortion of EM tracking.
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Affiliation(s)
- Hongliang Ren
- The Laboratory for Computational Sensing and Robotics, Department of Biomedical Engineering, The Johns Hopkins University.
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Favre J, Chardonnens J, Aminian K. An orientation measuring system suitable for routine uses made by the fusion of a 3D gyroscope and a magnetic tracker. ACTA ACUST UNITED AC 2007; 2007:3938-41. [PMID: 18002861 DOI: 10.1109/iembs.2007.4353195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Many studies have shown the efficacy of orientation and three-dimensional joint angle measurement for patient evaluation or rehabilitation purposes. But currently, the use of these systems for routine practice is questionable. The commercially available devices are generally too expensive and complicated-to-use. This study proposed the fusion between two affordable types of orientation measuring systems, which used separately couldn't satisfy the health professionals' needs. One was a portable magnetic tracker limited in accuracy, sampling frequency and possibly distorted. The other was triplets of gyroscopes limited by their bias, which generates orientation drift after integration. The fusion algorithm presented here relay on two cascaded complementary Kalman filters to estimate the bias of the gyroscopes and to provide accurate and high frequency orientation even during distortion periods. This system was assessed during treadmill walking and reported good performances.
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Affiliation(s)
- Julien Favre
- Laboratory of Movement Analysis and Measurement (LMAM) of the Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
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Hill AM, Bull AMJ, Dallalana RJ, Wallace AL, Johnson GR. Glenohumeral motion: review of measurement techniques. Knee Surg Sports Traumatol Arthrosc 2007; 15:1137-43. [PMID: 17431588 DOI: 10.1007/s00167-007-0318-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2006] [Accepted: 02/16/2007] [Indexed: 11/26/2022]
Abstract
Measurement of upper limb motion is problematic, not least because of the large range of path dependent description of motion of the joints, and the multiple non-cyclical unstandardised motion tasks measured. Furthermore, appreciation of shoulder motion specifically is obscured by overlying soft tissue. In order to satisfy the complexity of a clinically useful model of the movement of the joint, input data must be acquired from a set of pre-determined movements using a non-invasive technique with a high level of accuracy. Descriptive and predictive modeling of the glenohumeral joint requires input of high-fidelity data into a 6 degree of freedom representation, without which, the application of the tool is of limited clinical significance to the advancement of both operative and non-operative management of shoulder pathology. Electromagnetic, linkage and radiographic techniques have previously been used, however, an optimal solution is yet to be described.
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Affiliation(s)
- A M Hill
- Shoulder Bioengineering Group, Department of Bioengineering, Imperial College London, Sir Leon Bagrit Centre, Mechanical Engineering Building, South Kensington Campus, London, SW7 2AZ, UK
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Redmond AC, Crosbie J, Ouvrier RA. Development and validation of a novel rating system for scoring standing foot posture: the Foot Posture Index. Clin Biomech (Bristol, Avon) 2006; 21:89-98. [PMID: 16182419 DOI: 10.1016/j.clinbiomech.2005.08.002] [Citation(s) in RCA: 621] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2005] [Revised: 07/05/2005] [Accepted: 08/02/2005] [Indexed: 02/07/2023]
Abstract
INTRODUCTION The limitations of clinical methods for appraising foot posture are well documented. A new measure, the Foot Posture Index is proposed, and its development and validation described. METHODS A four-phase development process was used: (i) to derive a series of candidate measures, (ii) to define an appropriate scoring system, (iii) to evaluate the validity of components and modify the instrument as appropriate, and (iv) to investigate the predictive validity of the finalised instrument relative to static and dynamic kinematic models. Methods included initial concurrent validation using Rose's Valgus Index, determination of inter-item reliability, factor analysis, and benchmarking against three dimensional kinematic models derived from electromagnetic motion tracking of the lower limb. RESULTS Thirty-six candidate components were reduced to six in the final instrument. The draft version of the instrument predicted 59% of the variance in concurrent Valgus Index scores and demonstrated good inter item reliability (Cronbach's alpha = 0.83). The relevant variables from the motion tracking lower limb model predicted 58-80% of the variance in the six components retained in the final instrument. The finalised instrument predicted 64% of the variance in static standing posture, and 41% of the variance in midstance posture during normal walking. CONCLUSION The Foot Posture Index has been subjected to thorough evaluation in the course of its development and a final version is proposed comprising six component measures that performed satisfactorily during the validation process. The Foot Posture Index assessment is quick and simple to perform and allows a multiple segment, multiple plane evaluation that offers some advantages over existing clinical measures of foot posture.
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Affiliation(s)
- Anthony C Redmond
- Academic Unit of Musculoskeletal Disease, Rheumatology, University of Leeds, Chapel Allerton Hospital, UK.
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Schicho K, Figl M, Donat M, Birkfellner W, Seemann R, Wagner A, Bergmann H, Ewers R. Stability of miniature electromagnetic tracking systems. Phys Med Biol 2005; 50:2089-98. [PMID: 15843738 DOI: 10.1088/0031-9155/50/9/011] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This study aims at a comparative evaluation of two recently introduced electromagnetic tracking systems under reproducible simulated operating-room (OR) conditions: the recently launched Medtronic StealthStation, Treon-EM and the NDI Aurora. We investigate if and to what extent these systems provide improved performance and stability in the presence of surgical instruments as possible sources of distortions compared with earlier reports on electromagnetic tracking technology. To investigate possible distortions under pseudo-realistic OR conditions, a large Langenbeck hook, a dental drill with its handle and an ultrasonic (US) scanhead are fixed on a special measurement rack at variable distances from the navigation sensor. The position measurements made by the Treon-EM were least affected by the presence of the instruments. The lengths of the mean deviation vectors were 0.21 mm for the Langenbeck hook, 0.23 mm for the drill with handle and 0.56 mm for the US scanhead. The Aurora was influenced by the three sources of distortion to a higher degree. A mean deviation vector of 1.44 mm length was observed in the vicinity of the Langenbeck hook, 0.53 mm length with the drill and 2.37 mm due to the US scanhead. The maximum of the root mean squared error (RMSE) for all coordinates in the presence of the Langenbeck hook was 0.3 mm for the Treon and 2.1 mm for the Aurora; the drill caused a maximum RMSE of 0.2 mm with the Treon and 1.2 mm with the Aurora. In the presence of the US scanhead, the maximum RMSE was 1.4 mm for the Treon and 5.1 mm for the Aurora. The new generation of electromagnetic tracking systems has significantly improved compared to common systems that were available in the middle of the 1990s and has reached a high level of technical development. We conclude that, in general, both systems are suitable for routine clinical application.
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Affiliation(s)
- Kurt Schicho
- University Hospital of Cranio-Maxillofacial and Oral Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.
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Krempien R, Hassfeld S, Kozak J, Tuemmler HP, Däuber S, Treiber M, Debus J, Harms W. Frameless image guidance improves accuracy in three-dimensional interstitial brachytherapy needle placement. Int J Radiat Oncol Biol Phys 2004; 60:1645-51. [PMID: 15590197 DOI: 10.1016/j.ijrobp.2004.07.670] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2002] [Revised: 07/01/2004] [Accepted: 07/07/2004] [Indexed: 11/28/2022]
Abstract
PURPOSE The aim of this work was to adapt a computer-assisted real-time three-dimensional (3D) navigation system for interstitial brachytherapy procedures. METHODS AND MATERIALS The 3-D navigation system Surgical Planning and Orientation Computer System (SPOCS; Aesculap, Tuttlingen, Germany) was adapted for use in interstitial brachytherapy. A special needle holder with mounted infrared-emitting diodes (IRED) for 3D navigation-based needle implantation was developed. Measurements were made on a series of different phantoms to study the feasibility and the overall accuracy and precision of the navigation system with regard to single-needle application and volume implants (multiple-needle implantations). In all, 250 single implants and 20 volume implants were performed. Accuracy was measured as the target registration error (TRE) between the preoperatively defined and the achieved target position. RESULTS Analyses of the 250 different targets showed a mean TRE for single-needle applications of 1.1 mm (SD +/- 0.4 mm), 0.9 mm (SD +/- 0.3 mm), and 0.7 mm (SD +/- 0.3 mm) in the x, y, and z direction, respectively. The maximal deviation was 2.3 mm. The corresponding TRE in the x, y, and z direction for volume implants was 1.6 mm (SD +/- 0.4 mm), 1.9 mm (SD +/- 0.6 mm), and 1.0 mm (SD +/- 0.4 mm), respectively. The maximum deviation was 2.9 mm. CONCLUSIONS The adaptation of a commercially available surgical planning and navigation system to interstitial brachytherapy is feasible. It enables virtual planning and improved accuracy in 3D interstitial needle implantation.
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Affiliation(s)
- Robert Krempien
- Department of Clinical Radiology, University of Heidelberg, Heidelberg, Germany.
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Abstract
A review of CT-based orthopaedic navigation is presented with a specific emphasis on arthroplasty for the hip and the knee. Fundamental issues about the laboratory and clinical validation of the applications are addressed. The ability to compute the position and orientation of an acetabular implant using a postoperative CT scan was investigated. Angle deviations relative to known positions were computed with an error of less than 1 degree. Then, the system accuracy for three-dimensional reconstruction and registration of two cadaveric pelvis specimens was measured with more than 350 registrations. We observed a maximal inclination error of 5 degrees in 99% of cases and a maximal anteversion error of 5 degrees in 97% of cases. The accuracy of the three-dimensional reconstruction and registration for knee arthroplasty also was measured and computed with an angular accuracy of 0.5 degrees in the AP plane and accuracy of 3 degrees in the lateral plane. A clinical study then was done in 109 cases where 96% of implants were installed with a hip-knee-ankle angle of 180 +/- 3 degrees . Computed tomography-based navigation for orthopaedic surgery provides greater accuracy and reproducibility than conventional surgery. As noted by learning curves, software improvements are needed to bring it into daily clinical routine.
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Affiliation(s)
- Louis-Philippe Amiot
- Université de Montréal, Hopital Maisonneuve-Rosemont, Département d'orthopédie, Montreal, Quebec, Canada.
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