Name: handheld metal detector screening for metallic foreign body ingestion in children
Uploaded: 2018-09-11T15:00:00.000+00:00
Duration: 4 min 55 s
Description: Watch this Scientific Journal Video about Handheld Metal Detector Screening for Metallic Foreign Body Ingestion in Children at JoVE.com

The authors thank Dr. Lee Khai Pin, Head &#38; Senior Consultant, Children&#39;s Emergency, KK Women&#39;s and Children&#39;s Hospital, 100 Bukit Timah Road, Singapore for the administrative support with the video article production.&#160;Article reproduced with permission from &#8220;Handheld Metal Detector for Metallic Foreign Body Ingestion in Pediatric Emergency&#8221;; August 2018: 85(8):618&#8211;624; Hazwani Binte Hamzah, Vigil James, Suraj Manickam, Sashikumar Ganapathy: copyright The Indian Journal of Pediatrics.

The protocol follows the guidelines of Institutional Human Research Ethics committee. The central institutional review board provided the ethics approval for the study.
1. Participant Screening
<ol>
	<li>Recruit patients who present to the pediatric emergency department with history of foreign body ingestion.</li>
	<li>Exclude the patients who are in respiratory distress and has implanted devices like pace makers.</li>
</ol>
2. Prepare the Patient
<ol>
	<li>Dress the patient in a hospital gown.</li>
	<li>Remove all items that may contain metallic objects such as clothes, eye glasses, earrings, pendants, and ornaments prior to the examination to avoid interference with the HHMD screening.</li>
	<li>Place the patient in the center of the room away from other potential metallic interferences.</li>
</ol>
3. Prepare the Examiner and Caregivers
<ol>
	<li>Remove all metallic accessories such as jewelry and watch.</li>
	<li>Request the caregiver to remove all metallic accessories such as jewelry and watch.</li>
</ol>
4. Metal Detector Screening
<ol>
	<li>Use the HHMD (Figure 1) to conduct the screening.</li>
	<li>Confirm the working status of the HHMD by eliciting a positive audio-visual signal by waving over a piece of metal.</li>
	<li>Perform the HHMD scanning in a standing position for bigger children.</li>
	<li>Perform the HHMD scanning in an erect position for infants by having the caregiver hold the patient appropriately.</li>
	<li>Hold the hands of the patient up and away from the body.</li>
	<li>Position the head of the patient in extension to expose the neck.</li>
	<li>Scan from the level of the chin to the level of hip joint to cover the anatomical areas from neck to pelvis.</li>
	<li>Perform the scan in a zig-zag manner across the body to ensure that every area has been scanned.</li>
	<li>Scan both anteriorly and posteriorly as the thickness of patient must be taken into consideration.</li>
	<li>Carefully note the positive audio-visual signal during the scanning for the presence of MFBs.</li>
</ol>
5. Perform the Relevant Radiograph
<ol>
	<li>Order the relevant radiograph of the neck, chest, or abdomen, as per the area detected by the HHMD screening for the MFBs.</li>
	<li>Proceed with all the X-ray views (neck, chest, and abdomen) if the MFB was not detected during HHMD screening and the clinical index of suspicion for foreign body ingestion is high.</li>
</ol>
6. Record the Test Results
<ol>
	<li>Record the test results in the logbook (Figure 2) specifically created based on the workflow (Figure 1).</li>
	<li>Correlate the positive audio-visual HHMD signal with the underlying bony landmark on the body, by palpating the following prominent bony landmarks - sternal notch, xiphisternum, pubic symphysis, and bilateral Iliac crest.</li>
	<li>Record the landmark on the logbook&#39;s anatomical reference outline before proceeding with the X-ray examination.</li>
</ol>

<ol>
	<li>Lee, J., Ahmad, S., Gale, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detection+of+coins+ingested+by+children+using+a+handheld+metal+detector:+a+systematic+review.">Detection of coins ingested by children using a handheld metal detector: a systematic review.</a> Emergency Medicine Journal. 22 (12), 839-844 (2005).</li><li>Hesham A-Kader, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Foreign+body+ingestion:+children+like+to+put+objects+in+their+mouth.">Foreign body ingestion: children like to put objects in their mouth.</a> World Journal of Pediatrics. 6 (4), 301-310 (2010).</li><li>Muensterer, O. J., Joppich, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+and+topographic+localization+of+metallic+foreign+bodies+by+metal+detector.">Identification and topographic localization of metallic foreign bodies by metal detector.</a> Journal of Pediatric Surgery. 39 (8), 1245-1248 (2004).</li><li>Nation, J., Jiang, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+utility+of+a+handheld+metal+detector+in+detection+and+localization+of+pediatric+metallic+foreign+body+ingestion.">The utility of a handheld metal detector in detection and localization of pediatric metallic foreign body ingestion.</a> International Journal of Pediatric Otorhinolaryngology. 92, 1-6 (2017).</li><li>Arena, L., Baker, S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+a+metal+detector+to+identify+ingested+metallic+foreign+bodies.">Use of a metal detector to identify ingested metallic foreign bodies.</a> American Journal of Roentgenology. 155 (4), 803-804 (1990).</li><li>Younger, R. M., Darrow, D. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Handheld+metal+detector+confirmation+of+radiopaque+foreign+bodies+in+the+esophagus.">Handheld metal detector confirmation of radiopaque foreign bodies in the esophagus.</a> Archives of Otolaryngology--Head &amp; Neck Surgery. 127 (11), 1371-1374 (2001).</li><li>Schalamon, J., Haxhija, E. Q., Ainoedhofer, H., G&#246;ssler, A., Schleef, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+a+hand-held+metal+detector+for+localisation+of+ingested+metallic+foreign+bodies+-+a+critical+investigation.">The use of a hand-held metal detector for localisation of ingested metallic foreign bodies - a critical investigation.</a> European Journal of Pediatrics. 163 (4-5), 257-259 (2004).</li><li>Kay, M., Wyllie, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pediatric+foreign+bodies+and+their+management.">Pediatric foreign bodies and their management.</a> Current Gastroenterology Reports. 7 (3), 212-218 (2005).</li><li>Rothmann, B. F., Boeckman, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Foreign+bodies+in+the+larynx+and+tracheobronchial+tree+in+children.+A+review+of+225+cases.">Foreign bodies in the larynx and tracheobronchial tree in children. A review of 225 cases.</a> The Annals of Otology, Rhinology, and Laryngology. 89 (5), 434-436 (1980).</li><li>Pugmire, B. S., Lim, R., Avery, L. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Review+of+Ingested+and+Aspirated+Foreign+Bodies+in+Children+and+Their+Clinical+Significance+for+Radiologists.">Review of Ingested and Aspirated Foreign Bodies in Children and Their Clinical Significance for Radiologists.</a> Radiographics. 35 (5), 1528-1538 (2015).</li><li>Hodge, D., Tecklenburg, F., Fleisher, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coin+ingestion:+does+every+child+need+a+radiograph.">Coin ingestion: does every child need a radiograph.</a> Annals of Emergency Medicine. 14 (5), 443-446 (1985).</li><li>Schunk, J. E., Harrison, A. M., Corneli, H. M., Nixon, G. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluoroscopic+foley+catheter+removal+of+esophageal+foreign+bodies+in+children:+experience+with+415+episodes.">Fluoroscopic foley catheter removal of esophageal foreign bodies in children: experience with 415 episodes.</a> Pediatrics. 94 (5), 709-714 (1994).</li><li>Kerschner, J. E., Beste, D. J., Conley, S. F., Kenna, M. A., Lee, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mediastinitis+associated+with+foreign+body+erosion+of+the+esophagus+in+children.">Mediastinitis associated with foreign body erosion of the esophagus in children.</a> International Journal of Pediatric Otorhinolaryngology. 59 (2), 89-97 (2001).</li><li>Ahn, D., Heo, S. J., Park, J. H., Sohn, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tracheoesophageal+fistula+with+tracheal+stenosis+resulting+from+retained+esophageal+foreign+body.">Tracheoesophageal fistula with tracheal stenosis resulting from retained esophageal foreign body.</a> Auris Nasus Larynx. 38 (6), 753-756 (2011).</li><li>Dahiya, M., Denton, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Esophagoaortic+perforation+by+foreign+body+(coin)+causing+sudden+death+in+a+3-year-old+child.">Esophagoaortic perforation by foreign body (coin) causing sudden death in a 3-year-old child.</a> The American Journal of Forensic Medicine and Pathology. 20 (2), 184-188 (1999).</li><li>O'Brien, G. C., Winter, D. C., Kirwan, W. O., Redmond, H. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ingested+foreign+bodies+in+the+paediatric+patient.">Ingested foreign bodies in the paediatric patient.</a> Irish Journal of Medical Science. 170 (2), 100-102 (2001).</li><li>Bassett, K. E., Schunk, J. E., Logan, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Localizing+ingested+coins+with+a+metal+detector.">Localizing ingested coins with a metal detector.</a> The American Journal of Emergency Medicine. 17 (4), 338-341 (1999).</li><li>Gooden, E. A., Forte, V., Papsin, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+a+commercially+available+metal+detector+for+the+localization+of+metallic+foreign+body+ingestion+in+children.">Use of a commercially available metal detector for the localization of metallic foreign body ingestion in children.</a> The Journal of Otolaryngology. 29 (4), 218-220 (2000).</li><li>Sacchetti, A., Carraccio, C., Lichenstein, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hand-held+metal+detector+identification+of+ingested+foreign+bodies.">Hand-held metal detector identification of ingested foreign bodies.</a> Pediatric Emergency Care. 10 (4), 204-207 (1994).</li><li>Hamzah, H. B., James, V., Manickam, S., Ganapathy, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Handheld+Metal+Detector+for+Metallic+Foreign+Body+Ingestion+in+Pediatric+Emergency.">Handheld Metal Detector for Metallic Foreign Body Ingestion in Pediatric Emergency.</a> Indian Journal of Pediatrics. 85 (8), 618-624 (2018).</li><li>Doraiswamy, N. V., Baig, H., Hallam, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metal+detector+and+swallowed+metal+foreign+bodies+in+children.">Metal detector and swallowed metal foreign bodies in children.</a> Journal of Accident &amp; Emergency Medicine. 16 (2), 123-125 (1999).</li><li>Seikel, K., Primm, P. A., Elizondo, B. J., Remley, K. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Handheld+metal+detector+localization+of+ingested+metallic+foreign+bodies:+accurate+in+any+hands.">Handheld metal detector localization of ingested metallic foreign bodies: accurate in any hands.</a> Archives of Pediatrics &amp; Adolescent Medicine. 153 (8), 853-857 (1999).</li><li>Lemberg, P. S., Darrow, D. H., Holinger, L. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Aerodigestive+tract+foreign+bodies+in+the+older+child+and+adolescent.">Aerodigestive tract foreign bodies in the older child and adolescent.</a> The Annals of Otology, Rhinology, and Laryngology. 105 (4), 267-271 (1996).</li><li>Stack, L. B., Munter, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Foreign+bodies+in+the+gastrointestinal+tract.">Foreign bodies in the gastrointestinal tract.</a> Emergency Medicine Clinics of North America. 14 (3), 493-521 (1996).</li><li>Saz, E. U., Arikan, C., Ozgen&#231;, F., Duyu, M., Ozananar, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+utility+of+handheld+metal+detector+in+confirming+metallic+foreign+body+ingestion+in+the+pediatric+emergency+department.">The utility of handheld metal detector in confirming metallic foreign body ingestion in the pediatric emergency department.</a> The Turkish Journal of Gastroenterology: The Official Journal of Turkish Society of Gastroenterology. 21 (2), 135-139 (2010).</li></ol>

The authors have nothing to disclose.

Metallic foreign body ingestion in children is a common problem and in the majority of patients, this is managed conservatively7,16. Single or repeated radiographs can expose the radio-sensitive pediatric population to unwanted radiation risk while attempting to localize the ingested metallic foreign body. Several studies have described the use of metal detectors in MFB ingestion in children, with sensitivity more than 96% and specificity greater than 80%<sup cla...

Foreign body ingestion is a widespread problem among children presenting to the pediatric emergency department because of the natural inquisitive nature of infants and children to explore objects by tasting and swallowing them1,2. Previous studies have reported that metallic objects constituted 85% of all foreign body ingestions in their cohort of patients3,4. The goal of this protocol is to assess the accuracy and feasibility of using a handheld metal detector to detect ingested metallic foreign bodies in children. We propose that by introducing the handheld metal detector screening protocol early in the triage process of children with high suspicion of metallic foreign body ingestion, the number of radiographs being ordered to localize the metallic foreign body can be reduced in this radio-sensitive population.
Handheld metal detector (HHMD) is an inexpensive, easily accessible adjunct that can help expedite the management of ingested metallic foreign bodies. Metal detector is a very low frequency device, which has a receiver and a transmitter that detects the change in its electromagnetic field caused by the presence of a metallic object in its vicinity3. If a metallic object is within the field, the electromagnetic field is disrupted and the sensor will set off an audio-visual alarm on the device4. The metal detector examination can be thoroughly performed in less than 2 minutes5. Hence, the HHMD screening can be introduced early in the triage process of children with high suspicion of metallic foreign body ingestion for topographical localization.
Coins are the most common swallowed metallic foreign bodies1,4,6,7. Due to the lack of sharp edges and general non-toxic nature, the majority of coin ingestions are managed conservatively. Other types of materials commonly ingested include magnets, button batteries, small toys, peanuts, jewelry, buttons, bones, seeds, and popcorn8,9. Impaction of foreign bodies most commonly occurs in the esophagus at three sites, namely upper esophageal sphincter, mid-esophagus at the level of aortic arch, and lower esophageal sphincter10. Metallic foreign bodies (MFBs) located in the esophagus may be asymptomatic in 40% of patients11,12 and its prolonged impaction can lead to various complications like esophageal perforation, mediastinitis, tracheoesophageal fistula, tracheal stenosis, and aorto-esophageal fistulas1,13,14,15. Other locations of foreign body impaction include pylorus, duodenum, and ileo-caecal junction10.
Performing radiographs of neck, chest, and abdomen to diagnose suspected foreign body ingestion is a widespread practice in the emergency departments5. Among all types of the ingested foreign bodies, only 10% are radio-opaque10. The radiological tests are time-consuming and have a risk of radiation exposure in children. Precise topographical localization of ingested metal objects is very crucial to guide therapy. The introduction of HHMD screening early in the triage process can help mitigate extraneous ordering of radiographs by topographically localizing the ingested metallic foreign body.
This study evaluated the accuracy of HHMD to localize MFBs in a systematic topographic fashion and determined the effectiveness and feasibility of HHMD in the local Pediatric population. We also examined how well this radiation free screening tool was accepted by the patients and parents. Between May and July 2016, all the consecutive patients who presented to the pediatric emergency department with a history of foreign body ingestion were included in the study. Informed consent was obtained from the parent or legal guardian. Patients with alleged foreign body ingestion were systematically scanned using HHMD. The gold standard of care for identification and localization of ingested metallic foreign bodies is performing plain radiographs of the cervical area, thorax, and abdomen. To facilitate the conduct of the study, a standardized workflow was created (Figure 1). A log book specifically created based on the workflow was used to collect the initial data, which were subsequently transcribed to a spreadsheet (Figure 2). The data in the result section are depicted as the number of cases followed by percentages.

<table><tbody><tr><td>Hand held metal detector</td><td>Garrett Super Scanner V</td><td>NA</td><td>NA</td></tr></tbody></table>

handheld metal detector screening for metallic foreign body ingestion in children

Coins are the most common ingested metallic foreign bodies among children. The goal of this protocol is to assess the accuracy and feasibility of using a handheld metal detector to detect ingested metallic foreign bodies in children. We propose that by introducing handheld metal detector screening early in the triage process of children with high suspicion of metallic foreign body ingestion, the number of radiographs being ordered to localize the metallic foreign body can be reduced in this radio-sensitive population. The study protocol requires the screening of the participants for history of foreign body ingestion and exclusion of patients with respiratory distress or metallic implants. The patient changes to hospital gown and items that could contain metal like eyeglasses, earrings, pendants, and ornaments are removed. The patient is positioned in the center of the room away from other metallic interferences. The working status of the handheld metal detector is first confirmed by eliciting a positive audio-visual signal. Then the screening is done in an erect position with head in extension to expose the neck, from the level of the chin to the level of the hip joint, to cover the anatomical areas from neck to pelvis in a zig-zag manner both anteriorly and posteriorly. A positive audio-visual signal is carefully noted during the scanning for the presence of metallic foreign body. Relevant radiographs are ordered as per the area detected on the metal detector screening. The handheld metal detector was able to precisely identify all the coins among the ingested metallic foreign bodies in our study. The handheld metal detector could not consistently detect non-coin metallic foreign bodies. This protocol demonstrates the accuracy of handheld metal detector in the identification and localization of coins and coin like metallic foreign bodies.

The researchers recruited 36 patients for this observational study. These patients had presented to the pediatric emergency department with a history of foreign body ingestion. Among these, 28 patients had metallic foreign body ingestions (Figure 3). The remaining 8 patients had ingested non-metallic foreign bodies such as fish bones, satay stick, and plastic button. Coins were the most common type of foreign body ingested (Table 1), which co...

Watch this Scientific Journal Video about Handheld Metal Detector Screening for Metallic Foreign Body Ingestion in Children at JoVE.com

Handheld Metal Detector Screening for Metallic Foreign Body Ingestion in Children

Here, we present a protocol to use the handheld metal detector, to screen for the presence of ingested metallic foreign bodies in children who present to the pediatric emergency medicine department with a history of foreign body ingestion.

Coins are the most common ingested metallic foreign bodies among children. The goal of this protocol is to assess the accuracy and feasibility of using a ...

handheld-metal-detector-screening-for-metallic-foreign-body-ingestion

Research

JoVE Journal

Medicine

10.6K Views.  KK women's and Children's Hospital. Here, we present a protocol to use the handheld metal detector, to screen for the presence of ingested metallic foreign bodies in children who present to the pediatric emergency medicine department with a history of foreign body ingestion.

Video: Handheld Metal Detector Screening for Metallic Foreign Body Ingestion in Children

Bacterial Detection &amp; Identification Using Electrochemical Sensors

Electrochemical sensors are widely used for rapid and accurate measurement of blood glucose and can be adapted for detection of a wide variety of analytes. Electrochemical sensors operate by transducing a biological recognition event into a useful electrical signal. Signal transduction occurs by coupling the activity of a redox enzyme to an amperometric electrode. Sensor specificity is either an inherent characteristic of the enzyme, glucose oxidase in the case of a glucose sensor, or a product of linkage between the enzyme and an antibody or probe.
Here, we describe an electrochemical sensor assay method to directly detect and identify bacteria. In every case, the probes described here are DNA oligonucleotides. This method is based on sandwich hybridization of capture and detector probes with target ribosomal RNA (rRNA). The capture probe is anchored to the sensor surface, while the detector probe is linked to horseradish peroxidase (HRP). When a substrate such as 3,3',5,5'-tetramethylbenzidine (TMB) is added to an electrode with capture-target-detector complexes bound to its surface, the substrate is oxidized by HRP and reduced by the working electrode. This redox cycle results in shuttling of electrons by the substrate from the electrode to HRP, producing current flow in the electrode.

Bacterial Detection & Identification Using Electrochemical Sensors

We describe an electrochemical sensor assay method for rapid bacterial detection and identification. The assay involves a sensor array functionalized with DNA oligonucleotide capture probes for ribosomal RNA (rRNA) species-specific sequences. Sandwich hybridization of target rRNA with the capture probe and a horseradish peroxidase-linked DNA oligonucleotide detector probe produces a measurable amperometric current.

Electrochemical  sensors are widely used for rapid and accurate measurement of blood glucose and  can be adapted for detection of a wide variety of ...

Bioengineering

Protocol for the Evaluation of MRI Artifacts Caused by Metal Implants to Assess the Suitability of Implants and the Vulnerability of Pulse Sequences

As the number of magnetic resonance imaging (MRI) scanners and patients with medical implants is constantly growing, radiologists increasingly encounter metallic implant-related artifacts in MRI, resulting in reduced image quality. Therefore, the MRI suitability of implants in terms of artifact volume, as well as the development of pulse sequences to reduce image artifacts, are becoming more and more important. Here, we present a comprehensive protocol which allows for a standardized evaluation of the artifact volume of implants on MRI. Furthermore, this protocol can be used to analyze the vulnerability of different pulse sequences to artifacts. The proposed protocol can be applied to T1- and T2-weighted images with or without fat-suppression and all passive implants. Furthermore, the procedure enables the separate and three-dimensional identification of signal loss and pile-up artifacts. As previous investigations differed greatly in evaluation methods, the comparability of their results was limited. Thus, standardized measurements of MRI artifact volumes are necessary to provide better comparability. This may improve the development of the MRI suitability of implants and better pulse sequences to finally improve patient care.

We describe a standardized method to evaluate magnetic resonance imaging artifacts caused by implants to estimate the suitability of the implants for magnetic resonance imaging and/or the vulnerability of different pulse sequences to metallic artifacts simultaneously.

As the number of magnetic resonance imaging (MRI) scanners and patients with medical implants is constantly growing, radiologists increasingly encounter ...

Engineering

Making MR Imaging Child's Play - Pediatric Neuroimaging Protocol, Guidelines and Procedure

Within the last decade there has been an increase in the use of structural and functional magnetic resonance imaging (fMRI) to investigate the neural basis of human perception, cognition and behavior 1, 2. Moreover, this non-invasive imaging method has grown into a tool for clinicians and researchers to explore typical and atypical brain development. Although advances in neuroimaging tools and techniques are apparent, (f)MRI in young pediatric populations remains relatively infrequent 2. Practical as well as technical challenges when imaging children present clinicians and research teams with a unique set of problems 3, 2. To name just a few, the child participants are challenged by a need for motivation, alertness and cooperation. Anxiety may be an additional factor to be addressed. Researchers or clinicians need to consider time constraints, movement restriction, scanner background noise and unfamiliarity with the MR scanner environment2,4-10. A progressive use of functional and structural neuroimaging in younger age groups, however, could further add to our understanding of brain development. As an example, several research groups are currently working towards early detection of developmental disorders, potentially even before children present associated behavioral characteristics e.g.11. Various strategies and techniques have been reported as a means to ensure comfort and cooperation of young children during neuroimaging sessions. Play therapy 12, behavioral approaches 13, 14,15, 16-18 and simulation 19, the use of mock scanner areas 20,21, basic relaxation 22 and a combination of these techniques 23 have all been shown to improve the participant's compliance and thus MRI data quality. Even more importantly, these strategies have proven to increase the comfort of families and children involved 12. One of the main advances of such techniques for the clinical practice is the possibility of avoiding sedation or general anesthesia (GA) as a way to manage children's compliance during MR imaging sessions 19,20. In the current video report, we present a pediatric neuroimaging protocol with guidelines and procedures that have proven to be successful to date in young children.

Despite an increase in the use of structural and functional magnetic resonance imaging (fMRI) in humans, the study of young pediatric populations remains a challenge. We present a hands-on, step-by-step video protocol including guidelines for clinicians and researchers intending to perform (f)MRI in young children.

Within the last decade there has been an increase in the use of structural and functional magnetic resonance imaging (fMRI) to investigate the neural ...

Biology

Ferromagnetic Bare Metal Stent for Endothelial Cell Capture and Retention

Rapid endothelialization of cardiovascular stents is needed to reduce stent thrombosis and to avoid anti-platelet therapy which can reduce bleeding risk. The feasibility of using magnetic forces to capture and retain endothelial outgrowth cells (EOC) labeled with super paramagnetic iron oxide nanoparticles (SPION) has been shown previously. But this technique requires the development of a mechanically functional stent from a magnetic and biocompatible material followed by in-vitro and in-vivo testing to prove rapid endothelialization. We developed a weakly ferromagnetic stent from 2205 duplex stainless steel using computer aided design (CAD) and its design was further refined using finite element analysis (FEA). The final design of the stent exhibited a principal strain below the fracture limit of the material during mechanical crimping and expansion. One hundred stents were manufactured and a subset of them was used for mechanical testing, retained magnetic field measurements, in-vitro cell capture studies, and in-vivo implantation studies. Ten stents were tested for deployment to verify if they sustained crimping and expansion cycle without failure. Another 10 stents were magnetized using a strong neodymium magnet and their retained magnetic field was measured. The stents showed that the retained magnetism was sufficient to capture SPION-labeled EOC in our in-vitro studies. SPION-labeled EOC capture and retention was verified in large animal models by implanting 1 magnetized stent and 1 non-magnetized control stent in each of 4 pigs. The stented arteries were explanted after 7 days and analyzed histologically. The weakly magnetic stents developed in this study were capable of attracting and retaining SPION-labeled endothelial cells which can promote rapid healing.

Our goals were to design, manufacture and test ferromagnetic stents for endothelial cell capture. Ten stents were tested for fracture and 10 more stents were tested for retained magnetism. Finally, 10 stents were tested in-vitro and 8 more stents were implanted in 4 pigs to show cell capture and retention.

Rapid endothelialization of cardiovascular stents is needed to reduce stent thrombosis and to avoid anti-platelet therapy which can reduce bleeding risk. ...

Preparation and Application of a New Bacterial Biosensor for the Presumptive Detection of Gunshot Residue

MicRoboCop is a biosensor that has been designed for a unique application in forensic chemistry. MicRoboCop is a system made up of three devices that, when used together, can indicate the presence of gunshot residue (GSR) by producing a fluorescence signal in the presence of three key analytes (antimony, lead, and organic components of GSR). The protocol describes the synthesis of the biosensors using Escherichia coli (E. coli), and the analytical chemistry methods used to evaluate the selectivity and sensitivity of the sensors. The functioning of the system is demonstrated by using GSR collected from the inside of a spent cartridge casing. Once prepared, the biosensors can be stored until needed and can be used as a test for these key analytes. A positive response from all three analytes provides a presumptive positive test for GSR, while each individual device has applications for detecting the analytes in other samples (e.g., a detector for lead contamination in drinking water). The main limitation of the system is the time required for a positive signal; future work may involve studying different organisms to optimize the response time.

A protocol is presented using synthetic biology techniques to synthesize a set of bacterial biosensors for the analysis of gunshot residue, and to test the functioning of the devices for their intended use using fluorescence spectroscopy.

MicRoboCop is a biosensor that has been designed for a unique application in forensic chemistry. MicRoboCop is a system made up of three devices that, ...

Chemistry

Hellgrammite as a Non-Conventional Biomonitor for Surface Water and Environmental Health Assessment

The larvae of dobsonflies from the genus Corydalus, commonly known as Hellgrammites, are characterized by their notable size, extensive range of occurrence, and extended period of immaturity, which can last up to one year. Hellgrammites are clearly known to exhibit sensitivity to pollution and habitat structure impacts. Given these unique features, using Corydalus texanus larvae is highly suitable as reliable biomonitoring agents to assess the ecological integrity of aquatic ecosystems. This protocol aims to provide the necessary tools for C. texanus assessment and demonstrate their efficacy through a case study. Research findings have practical implications, indicating that C. texanus larvae exhibit early-warning responses to mining pollution, bioaccumulating high amounts of heavy metals such as Zn, Fe, and Al. The presence or absence of C. texanus populations may serve as a helpful indicator for identifying potential issues related to ecosystem health. The unconventional approach has shown early warnings of pollution in mining-impacted sites, highlighting the need for timely action to protect the environment. Given their unique traits, the use of C. texanus larvae is highly suggested as a reliable non-conventional bioindicator.

This protocol describes the use of biomarkers for the early detection of deleterious impacts in aquatic ecosystems. The biomarkers are closely related to sentinel traits, and their changes aid in detecting early-warning damages.

The larvae of dobsonflies from the genus Corydalus, commonly known as Hellgrammites, are characterized by their notable size, extensive range of ...

Environment

Quantification of Metal Leaching in Immobilized Metal Affinity Chromatography

Contamination of enzymes with metals leached from immobilized metal affinity chromatography (IMAC) columns poses a major concern for enzymologists, as many of the common di-and trivalent cations used in IMAC resins have an inhibitory effect on enzymes. However, the extent of metal leaching and the impact of various eluting and reducing reagents are poorly understood in large part due to the absence of simple and practical transition metal quantification protocols that use equipment typically available in biochemistry labs. To address this problem, we have developed a protocol to quickly quantify the amount of metal contamination in samples prepared using IMAC as a purification step. The method uses hydroxynaphthol blue (HNB) as a colorimetric indicator for metal cation content in a sample solution and UV-Vis spectroscopy as a means to quantify the amount of metal present, into the nanomolar range, based on the change in the HNB spectrum at 647 nm. While metal content in a solution has historically been determined using atomic absorption spectroscopy or inductively coupled plasma techniques, these methods require specialized equipment and training outside the scope of a typical biochemistry laboratory. The method proposed here provides a simple and fast way for biochemists to determine the metal content of samples using existing equipment and knowledge without sacrificing accuracy.

We present an assay for easy quantification of metals introduced to samples prepared using immobilized metal affinity chromatography. The method uses hydroxynaphthol blue as the colorimetric metal indicator and a UV-Vis spectrophotometer as the detector.

Contamination of enzymes with metals leached from immobilized metal affinity chromatography (IMAC) columns poses a major concern for enzymologists, as ...

Magnetic Levitation Coupled with Portable Imaging and Analysis for Disease Diagnostics

Currently, many clinical diagnostic procedures are complex, costly, inefficient, and inaccessible to a large population in the world. The requirements for specialized equipment and trained personnel require that many diagnostic tests be performed at remote, centralized clinical laboratories. Magnetic levitation is a simple yet powerful technique and can be applied to levitate cells, which are suspended in a paramagnetic solution and placed in a magnetic field, at a position determined by equilibrium between a magnetic force and a buoyancy force. Here, we present a versatile platform technology designed for point-of-care diagnostics which uses magnetic levitation coupled to microscopic imaging and automated analysis to determine the density distribution of a patient's cells as a useful diagnostic indicator. We present two platforms operating on this principle: (i) a smartphone-compatible version of the technology, where the built-in smartphone camera is used to image cells in the magnetic field and a smartphone application processes the images and to measures the density distribution of the cells and (ii) a self-contained version where a camera board is used to capture images and an embedded processing unit with attached thin-film-transistor (TFT) screen measures and displays the results. Demonstrated applications include: (i) measuring the altered distribution of a cell population with a disease phenotype compared to a healthy phenotype, which is applied to sickle cell disease diagnosis, and (ii) separation of different cell types based on their characteristic densities, which is applied to separate white blood cells from red blood cells for white blood cell cytometry. These applications, as well as future extensions of the essential density-based measurements enabled by this portable, user-friendly platform technology, will significantly enhance disease diagnostic capabilities at the point of care.

We present a magnetic levitation technique coupled with automated imaging and analysis in both a smartphone-compatible device and a device with embedded imaging and processing. This is applied to measure the density distribution of cells with two demonstrated biomedical applications: sickle cell disease diagnosis and separating white and red blood cells.

Currently, many clinical diagnostic procedures are complex, costly, inefficient, and inaccessible to a large population in the world. The requirements for ...

Magnetic Stirrer Method for the Detection of Trichinella Larvae in Muscle Samples

Trichinellosis is a debilitating disease in humans and is caused by the consumption of raw or undercooked meat of animals infected with the nematode larvae of the genus Trichinella. The most important sources of human infections worldwide are game meat and pork or pork products. In many countries, the prevention of human trichinellosis is based on the identification of infected animals by means of the artificial digestion of muscle samples from susceptible animal carcasses.
There are several methods based on the digestion of meat but the magnetic stirrer method is considered the gold standard. This method allows the detection of Trichinella larvae by microscopy after the enzymatic digestion of muscle samples and subsequent filtration and sedimentation steps. Although this method does not require special and expensive equipment, internal controls cannot be used. Therefore, stringent quality management should be applied throughout the test. The aim of the present work is to provide detailed handling instructions and critical control points of the method to analysts, based on the experience of the European Union Reference Laboratory for Parasites and the National Reference Laboratory of Germany for Trichinella.

Magnetic Stirrer Method for the Detection of Trichinella Larvae in Muscle Samples

The prevention of human trichinellosis in many countries worldwide is based on the laboratory examination of muscle samples from susceptible animals by methods of digestion, of which the magnetic stirrer method is considered the gold standard.

Trichinellosis is a debilitating disease in humans and is caused by the consumption of raw or undercooked meat of animals infected with the nematode ...

Immunology and Infection

Foodborne Pathogen Screening Using Magneto-fluorescent Nanosensor: Rapid Detection of E. Coli O157:H7

Enterohemorrhagic Escherichia coli O157:H7 has been linked to both waterborne and foodborne illnesses, and remains a threat despite the food- and water-screening methods used currently. While conventional bacterial detection methods, such as polymerase chain reaction (PCR) and enzyme-linked immunosorbent assays (ELISA) can specifically detect pathogenic contaminants, they require extensive sample preparation and lengthy waiting periods. In addition, these practices demand sophisticated laboratory instruments and settings, and must be executed by trained professionals. Herein, a protocol is proposed for a simpler diagnostic technique that features the unique combination of magnetic and fluorescent parameters in a nanoparticle-based platform. The proposed multiparametric magneto-fluorescent nanosensors (MFnS) can detect E. coli O157:H7 contamination with as little as 1 colony-forming unit present in solution within less than 1 h. Furthermore, the ability of MFnS to remain highly functional in complex media such as milk and lake water has been verified. Additional specificity assays were also used to demonstrate the ability of MFnS to only detect the specific target bacteria, even in the presence of similar bacterial species. The pairing of magnetic and fluorescent modalities allows for the detection and quantification of pathogen contamination in a wide range of concentrations, exhibiting its high performance in both early- and late-stage contamination detection. The effectiveness, affordability, and portability of the MFnS make them an ideal candidate for point-of-care screening for bacterial contaminants in a wide range of settings, from aquatic reservoirs to commercially packaged foods.

Foodborne Pathogen Screening Using Magneto-fluorescent Nanosensor: Rapid Detection of E. Coli O157:H7

The overall goal of this protocol is to synthesize functional nanosensors for the portable, cost-effective, and rapid detection of specifically targeted pathogenic bacteria through a combination of magnetic relaxation and fluorescence emission modalities.

Handheld Metal Detector Screening for Metallic Foreign Body Ingestion in Children

Podsumowanie

Przeglądaj więcej filmów

PLAYLIST