Systematic distortions in magnetic position digitizers

Birkfellner, Wolfgang; Watzinger, Franz; Wanschitz, Felix; Enislidis, Georg; Kollmann, Christian; Rafolt, D.; Nowotny, R.; Ewers, Rolf; Bergmann, Helmar

doi:10.1118/1.598425

Cited by 117 publications

(74 citation statements)

References 28 publications

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“…One possibility to reasonably compare these results is to consider the error as a percentage of the measured distance, as did Day et al [25] who found jitter errors up to 5 % and positional errors up to 3 % for the Polhemus Fastrak R system. Birkfellner et al compared the Polhemus Isotrak II R system to the Ascension Bird system and found the Isotrak II R to be more accurate but less robust against metallic distortions than the competing device [16]. Koerting assessed the Isotrak II R system in a thesis and found errors in the order of a couple of millimeters [82].…”

Section: B Study Resultsmentioning

confidence: 99%

“…Other Barratt et al [7] Position and rotation phantoms Yoo et al [207] Custom-build for C-arm Kirsch et al [74] Distortion of metals Birkfellner et al [16] 6 DoF Phantom, distortion assessment…”

Section: A Assessment Protocolsmentioning

confidence: 99%

“…More typically, an offline calibration procedure is performed. Published studues have shown a mean error reduction of 4-22 % [16,26,57]. Either way, the method should be repeatable, and should be performed quickly, immediately following the calibration, and without interfering with the medical procedure taking place at the same location (see Sec.…”

Section: Othermentioning

confidence: 99%

See 2 more Smart Citations

Electromagnetic Tracking in Medicine—A Review of Technology, Validation, and Applications

Franz

Haidegger

Birkfellner

et al. 2014

IEEE Trans. Med. Imaging

364

267

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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 lineof-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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Section: B Study Resultsmentioning

confidence: 99%

Section: A Assessment Protocolsmentioning

confidence: 99%

See 1 more Smart Citation

Electromagnetic Tracking in Medicine—A Review of Technology, Validation, and Applications

Franz

Haidegger

Birkfellner

et al. 2014

IEEE Trans. Med. Imaging

364

267

View full text Add to dashboard Cite

show abstract

“…Therefore the authors in [10] and [13] have used a commercial CAS system (ARTMA Virtual Patient System, ARTMA Medizintechnik Vienna, Austria) for implantology. These experiments utilized electromagnetic trackers which exhibit erratic behavior in metallic environments [2]; furthermore, a patient-to-CT registration protocol requiring a slice thickness of 3 mm was used. Therefore the accuracy reported was in the vicinity of 3 mm.…”

Section: Introductionmentioning

confidence: 99%

Computer-Aided Implant Dentistry

Birkfellner

Solar

Gahleitner

et al. 1999

Medical Image Computing and Computer-Assisted Intervention – MICCAI’99

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Abstract. Computer-aided implant dentistry (CAID), the direct translation of preoperative prosthetic planning to the operating theater by means of image guidance technologies, is a novel application of computer aided surgery (CAS). This work deals with the application of a modular software system for computer-aided interventions to CAID. The system is based on AVW-2.5, a software library dedicated to biomedical image processing, and a custom interface for communication with an optical tracker. A specific CAID toolset was also manufactured. We assessed the performance of two different point-based registration algorithms for this specific application of computer-aided preprosthetic surgery on several jaw models. The fiducial localization error (FLE) achievable with our system was found to be 0.7 mm, the fiducial registration error (FRE) accounted for 0.7 mm, and the target registration error TRE (the overall navigation accuracy) was found to be 1.3 mm. Since these results compare well to the resolution of the high-resolution computed tomography scan used we consider the precision of our system to be sufficient. Future enhancements of our system include the implementation of a medical augmented reality display system and the customization of the software package for exploration of other clinical applications of CAS.

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“…There are two main types of sensor; one that uses an AC (alternating current), and one a DC (direct current). Each is affected to some extent by the presence of metallic (AC sensors) or ferromagnetic (DC sensors) materials in the vicinity [24]. However, they allow complete freedom of movement, and do not require a line of sight.…”

Section: Automatic Position Sensingmentioning

confidence: 99%

Volume Measurement in Sequential Freehand 3-D Ultrasound

Treece

Prager

Gee

et al. 1999

Lecture Notes in Computer Science

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SummaryThree-dimensional (3D) acquisition and visualisation techniques are increasingly being incorporated into commercial ultrasound scanners. The diagnostic benefit of such techniques is not yet convincing, compared to the added inconvenience of using them. Although it is straightforward to use special probes to acquire 3D data, these are more restrictive than conventional 2D probes. The only 3D technique which retains the scanning flexibility and wide area of application of 2D ultrasound, is freehand 3D ultrasound, where a 2D probe is moved manually and its location sensed remotely. However, it is hard to generate a regular volume of data from the resulting non-parallel ultrasound images.Probably the largest body of evidence justifying the use of 3D ultrasound relates to the accurate measurement of volume. However, volume measurement with 3D ultrasound requires segmentation (i.e. outlining of the area of interest), which is a time consuming, manual task. Both this problem, and that of creating a regular volume of data, are eased by the use of sequential freehand 3D ultrasound, a recent technique amplified in this thesis, where all the processing is performed on the original ultrasound images. Thus a regular array of data is not required, and segmentation is performed on images whose features and artifacts are recognisable to the clinician.In this thesis, novel volume measurement and surface visualisation algorithms are developed for sequential freehand 3D ultrasound. A particular emphasis is placed on limiting the number of segmented cross-sections required for a given measurement accuracy. Inherent accuracy is demonstrated by simulation to be within ±2%, from 10 or fewer cross-sections. In vivo precision, including registration and segmentation errors, is shown to be within ±7%, even on complicated objects such as the liver or a foetus, from similar numbers of cross-sections. The volume can be updated in real-time as each image is segmented, and surfaces can be interpolated and visualised within a few seconds. Such visualisation can reveal errors in the segmentation which are otherwise hard to see.In addition, a framework for multiple-sweep data is developed, which allows volume measurement and surface visualisation of anatomy that can only be scanned by several sweeps of the ultrasound probe. Accurate volume measurements can therefore be made of all areas observable by conventional ultrasound. These measurements can be accomplished within approximately 5 minutes of examining the patient.The surface visualisation algorithms can also produce high quality renderings of data from a wide range of sources in medical imaging and other fields. The interpolation of cross-sections is an improvement on shape-based interpolation, and the triangular mesh created from the data is of a much higher quality than that using marching cubes. An extension of the surface interpolation algorithm can also be used to gradually change, or 'morph' one 3D surface to another, a technique commonly used in the film industry.

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Systematic distortions in magnetic position digitizers

Cited by 117 publications

References 28 publications

Electromagnetic Tracking in Medicine—A Review of Technology, Validation, and Applications

Electromagnetic Tracking in Medicine—A Review of Technology, Validation, and Applications

Computer-Aided Implant Dentistry

Volume Measurement in Sequential Freehand 3-D Ultrasound

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