PKBPNN-Based Tracking Range Extending Approach for TMR Magnetic Tracking System

This paper presents a tracking system using magnetometers, possibly integrable in a deep brain stimulation (DBS) electrode. DBS is a treatment for movement disorders where the position of the implant is of prime importance. Positioning challenges during the surgery could be addressed thanks to a magnetic tracking. The system proposed in this paper, complementary to existing procedures, has been designed to bridge preoperative clinical imaging with DBS surgery, allowing the surgeon to increase his/her control on the implantation trajectory. Here the magnetic source required for tracking consists of three coils, and is experimentally mapped. This mapping has been performed with an in-house three-dimensional magnetic camera. The system demonstrates how magnetometers integrated directly at the tip of a DBS electrode, might improve treatment by monitoring the position during and after the surgery. The three-dimensional operation without line of sight has been demonstrated using a reference obtained with magnetic resonance imaging (MRI) of a simplified brain model. We observed experimentally a mean absolute error of 1.35 mm and an Euclidean error of 3.07 mm. Several areas of improvement to target errors below 1 mm are also discussed.

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Magnetic Tracking: A Novel Method of Assessing Anterior Cruciate Ligament Deficiency

Annals of The Royal College of Surgeons of England ◽

10.1308/003588406x82934 ◽

2006 ◽

Vol 88 (1) ◽

pp. 16-17 ◽

Cited By ~ 2

Author(s):

RK Kundra ◽

JD Moorehead ◽

N Barton-Hanson ◽

SC Montgomery

Keyword(s):

Anterior Cruciate Ligament ◽

Tracking System ◽

Cruciate Ligament ◽

Magnetic Tracking ◽

Lachman Test ◽

Acl Deficiency ◽

Anterior Tibial ◽

Anterior Cruciate ◽

Tracking Device ◽

Acl Deficient

INTRODUCTION The Lachman test is commonly performed as part of the routine assessment of patients with suspected anterior cruciate ligament (ACL) deficiency. A major drawback is its reliance on the clinician's subjective judgement of movement. The aim of this study was to quantify Lachman movement using a magnetic tracking device thereby providing a more accurate objective measure of movement. PATIENTS AND METHODS Ten patients aged 21–51 years were assessed as having unilateral ACL deficiency with conventional clinical tests. These patients were then re-assessed using a Polhemus Fastrak™ magnetic tracking device. RESULTS The mean anterior tibial displacement was 5.6 mm (SD = 2.5) for the normal knees and 10.2 mm (SD = 4.2) for the ACL-deficient knees. This gave an 82% increase in anterior tibial displacement for the ACL deficient knees. This was shown to be highly significant with P = 0.005. CONCLUSIONS The magnetic tracking system offers an objective quantification of displacements during the Lachman test. It is convenient, non-invasive and comfortable for the patient and is, therefore, ideally suited for use as an investigative tool.

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Development of a magnetic tracking system for monitoring soil movements induced by geohazards

E3S Web of Conferences ◽

10.1051/e3sconf/20199217007 ◽

2019 ◽

Vol 92 ◽

pp. 17007 ◽

Cited By ~ 2

Author(s):

Xiaoyu Chen ◽

Rolando P. Orense

Keyword(s):

Magnetic Fields ◽

Permanent Magnets ◽

Tracking System ◽

Soil Liquefaction ◽

Small Scale ◽

Interior Point Algorithm ◽

Tracking Accuracy ◽

Tracking Errors ◽

Magnetic Tracking ◽

Soil Movements

In the study of geotechnical hazards, such as soil liquefaction and landslides, the analysis of soil movements is always one of the major preoccupations. An efficient movement sensing technique requires the tracking of subsurface soil for the purpose of examining the mechanism involved. A magnetic tracking system is therefore proposed, with permanent magnets as trackers and magnetometers as receivers. When permanent magnets, deployed within the soil to serve as excitation sources, move with soil body during a geotechnical event, they generate static magnetic fields whose flux densities are related with the positions and orientations of the magnets. Magnetometers are used as receivers to detect the generated magnetic fields, which can be further used in calculating the magnets' locations and orientations based on appropriately developed algorithms. Comparison between situations where the trackers are exposed to air and embedded within soil was conducted to evaluate the influence of soil (wet and dry) on the tracking accuracy. Also, multi-objective tracking is realized by using the particle swarm optimization (PSO) technique combined with interior-point algorithm. The tracking errors are evaluated and applications of the proposed system in small-scale laboratory tests for geohazards are discussed.

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Wireless magnetic tracking system for radiation therapy

2009 IEEE/NIH Life Science Systems and Applications Workshop ◽

10.1109/lissa.2009.4906731 ◽

2009 ◽

Cited By ~ 2

Author(s):

Tae-young Choi ◽

Wing Fai Loke ◽

Teimour Maleki ◽

Babak Ziaie ◽

Lech Papiez ◽

...

Keyword(s):

Radiation Therapy ◽

Tracking System ◽

Magnetic Tracking

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Tracking of Brain Tumors using Vision and Neurosonography

Applied Bionics and Biomechanics ◽

10.1155/2010/496754 ◽

2010 ◽

Vol 7 (2) ◽

pp. 123-130

Author(s):

Rubén Machucho Cadena ◽

Sergio de la Cruz Rodríguez ◽

Eduardo Bayro-Corrochano

Keyword(s):

Brain Tumors ◽

Hough Transform ◽

Geometric Algebra ◽

Brain Tumours ◽

Tracking System ◽

Ultrasound Image ◽

The Other ◽

Ultrasound Probe ◽

Geometric Transformations ◽

Magnetic Tracking

We have developed a method to render brain tumours from endoneurosonography. We propose to track an ultrasound probe in successive endoscopic images without relying on an external optic or magnetic tracking system. The probe is tracked using two different methods: one of them based on a generalised Hough transform and the other one based on particle filters. By estimating the pose of the ultrasound probe in several contiguous images, we use conformal geometric algebra to compute the geometric transformations that yield the 3D position of the tumour, which was segmented in the ultrasound image using morphological operators. We use images from brain phantoms to evaluate the performance of the proposed methods, and our results show that they are robust.

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