scholarly journals Innovative Differential Magnetic Localization Method for Capsule Endoscopy to Prevent Interference Caused by the Geomagnetic Field

2021 ◽  
Author(s):  
Samuel Zeising ◽  
Daisuke Anzai ◽  
Angelika Thalmayer ◽  
Georg Fischer ◽  
Jens Kirchner
Keyword(s):  
Capsule Endoscopy ◽  
Geomagnetic Field ◽  
Medical Application ◽  
Differential Method ◽  
Localization Accuracy ◽  
Localization Method ◽  
Marquardt Algorithm ◽  
Position And Orientation ◽  
Wireless Capsule ◽  
The Impact

Wireless capsule endoscopy is an established medical application for the examination of the gastrointestinal tract. However, the robust and precise localization of these capsules is still in need of further scientific investigation. This paper presents an innovative differential magnetic localization method for capsule endoscopy to prevent interference caused by the geomagnetic field. The effect of changing the orientation of the capsule on the localization process was also examined. Simulations using COMSOL Multiphysics with the superimposed geomagnetic field were performed. The Levenberg–Marquardt algorithm was applied in MATLAB to estimate the position and orientation of the capsule. Comparing the proposed differential method with the absolute magnetic localization method under ideal conditions, the mean position and orientation errors were reduced by three orders in magnitude to less than 0.1 mm and 0.1 ° respectively. Even if sensor non-idealities are considered, the simulationbased results reveal that our proposed method is competitive with state-of-the-art geomagnetic compensation methods for static magnetic localization of capsule endoscopes.The achieved localization accuracy by applying the differential method is not dependent on the rotation of the localization system relative to the geomagnetic flux density under the made assumptions and the impact of the magnet orientation is neglectable. It is concluded that the proposed method is capable of preventing all interference whose components are approximately equal at all sensors with identical orientation. <br>

scholarly journals Innovative Differential Magnetic Localization Method for Capsule Endoscopy to Prevent Interference Caused by the Geomagnetic Field

2021 ◽  
Author(s):  
Samuel Zeising ◽  
Daisuke Anzai ◽  
Angelika Thalmayer ◽  
Georg Fischer ◽  
Jens Kirchner
Keyword(s):  
Capsule Endoscopy ◽  
Geomagnetic Field ◽  
Medical Application ◽  
Differential Method ◽  
Localization Accuracy ◽  
Localization Method ◽  
Marquardt Algorithm ◽  
Position And Orientation ◽  
Wireless Capsule ◽  
The Impact

Wireless capsule endoscopy is an established medical application for the examination of the gastrointestinal tract. However, the robust and precise localization of these capsules is still in need of further scientific investigation. This paper presents an innovative differential magnetic localization method for capsule endoscopy to prevent interference caused by the geomagnetic field. The effect of changing the orientation of the capsule on the localization process was also examined. Simulations using COMSOL Multiphysics with the superimposed geomagnetic field were performed. The Levenberg–Marquardt algorithm was applied in MATLAB to estimate the position and orientation of the capsule. Comparing the proposed differential method with the absolute magnetic localization method under ideal conditions, the mean position and orientation errors were reduced by three orders in magnitude to less than 0.1 mm and 0.1 ° respectively. Even if sensor non-idealities are considered, the simulationbased results reveal that our proposed method is competitive with state-of-the-art geomagnetic compensation methods for static magnetic localization of capsule endoscopes.The achieved localization accuracy by applying the differential method is not dependent on the rotation of the localization system relative to the geomagnetic flux density under the made assumptions and the impact of the magnet orientation is neglectable. It is concluded that the proposed method is capable of preventing all interference whose components are approximately equal at all sensors with identical orientation. <br>

scholarly journals Innovative Differential Magnetic Localization Method for Capsule Endoscopy to Prevent Interference Caused by the Geomagnetic Field

2021 ◽  
Vol 19 ◽  
pp. 207-213
Author(s):  
Samuel Zeising ◽  
Daisuke Anzai ◽  
Angelika Thalmayer ◽  
Georg Fischer ◽  
Jens Kirchner
Keyword(s):  
Capsule Endoscopy ◽  
Geomagnetic Field ◽  
Medical Application ◽  
Differential Method ◽  
Localization Accuracy ◽  
Localization Method ◽  
Marquardt Algorithm ◽  
Capsule Endoscopes ◽  
Position And Orientation ◽  
The Impact

Abstract. Wireless capsule endoscopy is an established medical application for the examination of the gastrointestinal tract. However, the robust and precise localization of these capsules is still in need of further scientific investigation. This paper presents an innovative differential magnetic localization method for capsule endoscopy to prevent interference caused by the geomagnetic field. The effect of changing the orientation of the capsule on the localization process was also examined. Simulations using COMSOL Multiphysics with the superimposed geomagnetic field were performed. The Levenberg–Marquardt algorithm was applied in MATLAB to estimate the position and orientation of the capsule. Comparing the proposed differential method with the absolute magnetic localization method under ideal conditions, the mean position and orientation errors were reduced by three orders in magnitude to less than 0.1 mm and 0.1∘ respectively. Even if sensor non-idealities are considered, the simulation-based results reveal that our proposed method is competitive with state-of-the-art geomagnetic compensation methods for static magnetic localization of capsule endoscopes. The achieved localization accuracy by applying the differential method is not dependent on the rotation of the localization system relative to the geomagnetic flux density under the made assumptions and the impact of the magnet orientation is neglectable. It is concluded that the proposed method is capable of preventing all interference whose components are approximately equal at all sensors with identical orientation.

scholarly journals Evaluation of the Impact of Static Interference on an Empirical Data Based Static Magnetic Localization Setup for Capsule Endoscopy

2020 ◽  
Vol 6 (3) ◽  
pp. 66-69
Author(s):  
Samuel Zeising ◽  
Daisuke Anzai ◽  
Angelika Thalmayer ◽  
Georg Fischer ◽  
Jens Kirchner
Keyword(s):  
Magnetic Flux ◽  
Flux Density ◽  
Capsule Endoscopy ◽  
Empirical Data ◽  
Geomagnetic Field ◽  
Sensor Array ◽  
Magnetic Flux Density ◽  
Wearable Sensor ◽  
Differential Measurement ◽  
The Impact

AbstractIn this paper, the impact of interference due to the geomagnetic field on a static magnetic localization setup for capsule endoscopy, which is suitable for a wearable application, was investigated. For this purpose, a study was carried out in which the average abdomen size of 15 subjects was evaluated. With the determined geometry values, a setup consisting of three elliptical sensor rings was modeled. Simulations were performed, where the magnetic flux density was evaluated at the sensors by using different-sized magnets. The measured values were compared with each other and the geomagnetic flux density. The results revealed that the measured values were for all evaluated magnet sizes of the order of the geomagnetic flux density, which is problematic since the calibration of sensors is no longer valid if the orientation of the wearable sensor array is changed. However, it is suggested that a differential measurement is suitable for the proposed system and could reduce static interference caused by the geomagnetic field.

Hollow Receiving Coil and Single Turn Element Analysis on Power for Wireless Capsule Endoscopy

2020 ◽  
Vol 10 (11) ◽  
pp. 2714-2721
Author(s):  
Shuai Kuang ◽  
Guozheng Yan ◽  
Zhiwu Wang ◽  
Pingping Jiang ◽  
Ding Han
Keyword(s):  
Capsule Endoscopy ◽  
Power Supply ◽  
Wireless Capsule Endoscopy ◽  
Image Resolution ◽  
Computational Time ◽  
Element Analysis ◽  
Single Turn ◽  
Receiving Coil ◽  
Position And Orientation ◽  
Wireless Capsule

Wireless capsule endoscopy (WCE) is more and more popular in noninvasive detection on gastrointestinal (GI) disease. But the power supply is still a bottleneck. Insufficient power reduces image resolution and frame rate of data transfer, thus, unreliable medical diagnosis. Wireless power transmission (WPT) technology enables power supply for WCE. A hollow receiving coil (RC) with novel structure is proposed to minimize the capsule scale and solve the power issue. Single turn element analysis (STEA) is adopted to directly evaluate receiving power. Receiving power varies greatly when WCE is in different position and orientation of GI tract during the detection process. In some particular misalignment, power drops too low or jumps frequently. Then, optimization design of RC aimed at sufficient and stable power supply is implemented. The STEA is validated on test bench. The error of electromagnetic force is 0.2 V. The least receiving power with the optimal RC is 438.1 mW even in the worst misalignment. In the great majority of position and orientation misalignments, the optimal RC receives power over 650 mW. With the advantage of both computational time and accuracy, STEA is applicable for measurement and analysis on power for biomedical devices utilizing WPT technology, not merely WCE. In vivo experiment in pig's GI is accomplished with the optimal RC. The size of WCE with the novel RC gets smaller. And image stream is clear and fluent, when WCE is in any possible position and orientation of the tract. Four frames are stochastically sampled, in entropy of 7.1148, 7.3070, 7.2041, and 7.2570. Sufficient and stable power supply with the hollow RC enables advanced functions like drug release to come into being in WCE.

Wireless Capsule Endoscopy – Uses Beyond GI Bleeding?

Endoscopy ◽  
2006 ◽  
Vol 38 (11) ◽  
Author(s):  
P McConville ◽  
WJ Cash ◽  
RGP Watson ◽  
JS Collins
Keyword(s):  
Capsule Endoscopy ◽  
Wireless Capsule Endoscopy ◽  
Gi Bleeding ◽  
Wireless Capsule

The Role of Wireless Capsule Endoscopy (WCE) in the Detection of Occult Primary Neuroendocrine Tumors

2017 ◽  
Vol 26 (2) ◽  
pp. 151-156
Author(s):  
Manuele Furnari ◽  
Andrea Buda ◽  
Gabriele Delconte ◽  
Davide Citterio ◽  
Theodor Voiosu ◽  
...  
Keyword(s):  
Neuroendocrine Tumor ◽  
Neuroendocrine Tumors ◽  
Capsule Endoscopy ◽  
Primary Tumor ◽  
Diagnostic Yield ◽  
Somatostatin Receptor ◽  
Tertiary Care ◽  
Wireless Capsule Endoscopy ◽  
First Line ◽  
Wireless Capsule

Background & Aims: Neuroendocrine tumors (NETs) are a heterogeneous group of neoplasms with unclear etiology that may show functioning or non-functioning features. Primary tumor localization often requires integrated imaging. The European Neuroendocrine Tumors Society (ENETS) guidelines proposed wireless-capsule endoscopy (WCE) as a possible diagnostic tool for NETs, if intestinal origin is suspected. However, its impact on therapeutic management is debated. We aimed to evaluate the yield of WCE in detecting intestinal primary tumor in patients showing liver NET metastases when first-line investigations are inconclusive.Method: Twenty-four patients with histological diagnosis of metastatic NET from liver biopsy and no evidence of primary lesions at first-line investigations were prospectively studied in an ENETS-certified tertiary care center. Wireless-capsule endoscopy was requested before explorative laparotomy and intra-operative ultrasound. The diagnostic yield of WCE was compared to the surgical exploration.Results: Sixteen subjects underwent surgery; 11/16 had positive WCE identifying 16 bulging lesions. Mini-laparotomy found 13 NETs in 11/16 patients (9 small bowel, 3 pancreas, 1 bile ducts). Agreement between WCE and laparotomy was recorded in 9 patients (Sensitivity=75%; Specificity=37.5%; PPV=55%; NPV=60%). Correspondence assessed per-lesions produced similar results (Sensitivity=70%; Specificity=25%; PPV=44%; NPV=50%). No capsule retentions were recorded.Conclusions: Wireless-capsule endoscopy is not indicated as second-line investigation for patients with gastro-entero-pancreatic NETs. In the setting of a referral center, it might provide additional information when conventional investigations are inconclusive about the primary site.Abbreviations: DBE: double balloon enteroscopy; GEP-NET: gastro-entero-pancreatic neuroendocrine tumor; GI: gastrointestinal; ENETS: European Neuroendocrine Tumor Society; NET: neuroendocrine tumor; SSRS: somatostatin receptor scintigraphy; WCE: wireless capsule endoscopy.

Sign in / Sign up

Export Citation Format

Share Document