RESUMEN
Wireless medical telemetry systems (WMTSs) are typical radio communication-based medical devices that monitor various biological parameters, such as electrocardiograms and respiration rates. In Japan, the assigned frequency band for WMTSs is 400 MHz. However, the issues accounting for poor reception in WMTS constitute major concerns. In this study, we analyzed the effects of electromagnetic interferences (EMIs) caused by other radio communication systems, the intermodulation (IM) effect, and noises generated from electrical devices on WMTS and discussed their management. The 400-MHz frequency band is also shared by other radio communication systems. We showed the instantaneous and impulsive voltages generated from the location-detection system for wandering patients and their potential to exhibit EMI effects on WMTS. Further, we presented the IM effect significantly reduces reception in WMTS. Additionally, the electromagnetic noises generated from electrical devices, such as light-emitting diode lamps and security cameras, can exceed the 400 MHz frequency band as these devices employ the switched-mode power supply and/or central processing unit and radiate wideband emissions. Moreover, we proposed and evaluated simple and facile methods using a simplified spectrum analysis function installed in the WMTS receiver and software-defined radio for evaluating the electromagnetic environment.
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Telemetría , Tecnología Inalámbrica , Tecnología Inalámbrica/instrumentación , Telemetría/instrumentación , Telemetría/métodos , Humanos , Campos Electromagnéticos , Fenómenos ElectromagnéticosRESUMEN
Understanding the movement patterns of an invasive species can be a powerful tool in designing effective management and control strategies. Here, we used a Bayesian multistate model to investigate the movement of two invasive carp species, silver carp (Hypophthalmichthys molitrix) and bighead carp (H. nobilis), using acoustic telemetry. The invaded portions of the Illinois and Des Plaines Rivers, USA, are a high priority management zone in the broader efforts to combat the spread of invasive carps from reaching the Laurentian Great Lakes. Our main objective was to characterize the rates of upstream and downstream movements by carps between river pools that are maintained by navigation lock and dam structures. However, we also aimed to evaluate the efficacy of the available telemetry infrastructure to monitor carp movements through this system. We found that, on a monthly basis, most individuals of both species remained within their current river pools: averaging 76.2% of silver carp and 75.5% of bighead carp. Conversely, a smaller proportion of silver carp, averaging 14.2%, and bighead carp, averaging 13.9%, moved to downstream river pools. Movements towards upstream pools were the least likely for both species, with silver carp at an average of 6.7% and bighead carp at 7.9%. The highest probabilities for upstream movements were for fish originating from the three most downstream river pools, where most of the population recruitment occurs. However, our evaluation of the telemetry array's effectiveness indicated low probability to detect fish in this portion of the river. We provide insights to enhance the placement and use of these monitoring tools, aiming to deepen our comprehension of these species' movement patterns in the system.
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Teorema de Bayes , Carpas , Especies Introducidas , Ríos , Telemetría , Animales , Telemetría/métodos , Telemetría/instrumentación , Telemetría/veterinaria , Carpas/fisiología , Illinois , Migración Animal/fisiologíaRESUMEN
The use of telemetry techniques to better understand the behavior and survival of juvenile American shad (Alosa sapidissima), as they migrate through hydropower systems, has been challenging because shad are widely known to be particularly sensitive to handling. The goal of this study was to develop a tagging protocol using a new, acoustic micro transmitter that minimizes the detrimental effects of the tagging process and maximizes post-tagging survival of juvenile American shad. Limiting out-of-water handling and the use of brackish saltwater (7.5 parts per thousand) before and after tagging improved survival for shad tagged using a simple pectoral implantation method. This protocol provides a detailed, step-by-step procedure for tagging juvenile shad with acoustic transmitters. Fish tagged using this procedure and held in the laboratory for 60 days had an 81.5% survival rate, compared to 70% for their untagged counterparts. The successful tagging and handling practices developed in this study could be applied to field telemetry studies of juvenile shad and other sensitive species.
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Acústica , Telemetría , Animales , Acústica/instrumentación , Telemetría/métodos , Telemetría/instrumentación , Sistemas de Identificación Animal/métodos , Sistemas de Identificación Animal/instrumentaciónRESUMEN
In this paper, we present the design of a millimeter-wave 1 × 4 linear MIMO array antenna that operates across multiple resonance frequency bands: 26.28-27.36 GHz, 27.94-28.62 GHz, 32.33-33.08 GHz, and 37.59-39.47 GHz, for mm-wave wearable biomedical telemetry application. The antenna is printed on a flexible substrate with dimensions of 11.0 × 44.0 mm2. Each MIMO antenna element features a modified slot-loaded triangular patch, incorporating 'cross'-shaped slots in the ground plane to improve impedance matching. The MIMO antenna demonstrates peak gains of 6.12, 8.06, 5.58, and 8.58 dBi at the four resonance frequencies, along with a total radiation efficiency exceeding 75%. The proposed antenna demonstrates excellent diversity metrics, with an ECC < 0.02, DG > 9.97 dB, and CCL below 0.31 bits/sec/Hz, indicating high performance for mm-wave applications. To verify its properties under flexible conditions, a bending analysis was conducted, showing stable S-parameter results with deformation radii of 40 mm (Rx) and 25 mm (Ry). SAR values for the MIMO antenna are calculated at 28.0/38.0 GHz. The average SAR values for 1 gm/10 gm of tissues at 28.0 GHz are found to be 0.0125/0.0079 W/Kg, whereas, at 38.0 GHz, average SAR values are 0.0189/0.0094 W/Kg, respectively. Additionally, to demonstrate the telemetry range of biomedical applications, a link budget analysis at both 28.0 GHz and 38.0 GHz frequencies indicated strong signal strength of 33.69 dB up to 70 m. The fabricated linear MIMO antenna effectively covers the mm-wave 5G spectrum and is suitable for wearable and biomedical applications due to its flexible characteristics.
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Telemetría , Dispositivos Electrónicos Vestibles , Telemetría/instrumentación , Telemetría/métodos , Humanos , Tecnología Inalámbrica/instrumentación , Diseño de EquipoRESUMEN
Hemodialysis is achieved by implanting a smart arteriovenous graft (AVG) to build a vascular pathway, but reliability and stability in data transmission cannot be guaranteed. To address this issue, a miniaturized dual-band circularly polarized implantable antenna operating at 1.4 GHz (for energy transmission) and 2.45 GHz (for wireless telemetry), implanted in a wireless arteriovenous graft monitoring device (WAGMD), has been designed. The antenna design incorporates a rectangular serpentine structure on the radiation surface to reduce its volume to 9.144 mm3. Furthermore, matching rectangular slots on the radiation surface and the ground plane enhance the antenna's circular polarization performance. The simulated effective 3 dB axial ratio (AR) bandwidths are 11.43% (1.4 GHz) and 12.65% (2.45 GHz). The simulated peak gains of the antenna are -19.55 dBi and -22.85 dBi at 1.4 GHz and 2.45 GHz, respectively. The designed antenna is implanted in a WAGMD both in the simulation and the experiment. The performance of the system is simulated in homogeneous human tissue models of skin, fat, and muscle layers, as well as a realistic adult male forearm model. The measurement results in a minced pork environment align closely with the simulation results.
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Diálisis Renal , Tecnología Inalámbrica , Diálisis Renal/instrumentación , Humanos , Tecnología Inalámbrica/instrumentación , Telemetría/instrumentación , Diseño de Equipo , Prótesis e Implantes , MasculinoRESUMEN
Objective. We intend to chronically restore somatosensation and provide high-fidelity myoelectric control for those with limb loss via a novel, distributed, high-channel-count, implanted system.Approach.We have developed the implanted Somatosensory Electrical Neurostimulation and Sensing (iSens®) system to support peripheral nerve stimulation through up to 64, 96, or 128 electrode contacts with myoelectric recording from 16, 8, or 0 bipolar sites, respectively. The rechargeable central device has Bluetooth® wireless telemetry to communicate to external devices and wired connections for up to four implanted satellite stimulation or recording devices. We characterized the stimulation, recording, battery runtime, and wireless performance and completed safety testing to support its use in human trials.Results.The stimulator operates as expected across a range of parameters and can schedule multiple asynchronous, interleaved pulse trains subject to total charge delivery limits. Recorded signals in saline show negligible stimulus artifact when 10 cm from a 1 mA stimulating source. The wireless telemetry range exceeds 1 m (direction and orientation dependent) in a saline torso phantom. The bandwidth supports 100 Hz bidirectional update rates of stimulation commands and data features or streaming select full bandwidth myoelectric signals. Preliminary first-in-human data validates the bench testing result.Significance.We developed, tested, and clinically implemented an advanced, modular, fully implanted peripheral stimulation and sensing system for somatosensory restoration and myoelectric control. The modularity in electrode type and number, including distributed sensing and stimulation, supports a wide variety of applications; iSens® is a flexible platform to bring peripheral neuromodulation applications to clinical reality. ClinicalTrials.gov ID NCT04430218.
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Electromiografía , Humanos , Electromiografía/métodos , Electrodos Implantados , Tecnología Inalámbrica/instrumentación , Telemetría/instrumentación , Telemetría/métodos , Diseño de Equipo/métodos , Músculo Esquelético/fisiología , Músculo Esquelético/inervaciónRESUMEN
INTRODUCTION: Rat telemetry is the assay of choice to assess the potential effects of novel drug candidates on cardiovascular parameters during early drug discovery. Telemetry device implantation can be combined with venous catheter and access button implantation when intravenous administration of the drug substance is required. METHODS: Rats (Sprague Dawley or Han Wistar) were implanted with telemetry devices for arterial blood pressure measurement using either direct aortic catheterisation (n = 131) or aortic catheterisation via the femoral artery (n = 17). Bipolar leads for ECG recording were also implanted in some of the animals (n = 102). Femoral vein catheters and access buttons were implanted as a separate surgery after the initial telemetry implantation (n = 43). RESULTS: 128 animals (86%) were implanted successfully with telemetry devices without any notable surgical or post-surgical problems. When considering the 2 different catheterisation methods separately, the success rate of the direct aortic approach was 88% compared to 76% with the aortic placement via the femoral artery. Lameness was the most common post-surgical problem. Blood loss during surgery and ischaemic patches on the tail were also observed at a low incidence with the direct aortic approach. Catheter pull-out occurred in some rats before the first signal check reducing the overall success rate for blood pressure measurement using the direct aortic approach to 85%. A 95% success rate was observed for catheter and access button implantation. DISCUSSION: A high success rate is possible when implanting telemetry devices in rats with and without venous catheters and access buttons. We have attempted to provide solutions to problems and describe refinements to the procedure which may further improve surgical outcomes.
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Ratas Sprague-Dawley , Ratas Wistar , Telemetría , Animales , Telemetría/métodos , Telemetría/instrumentación , Ratas , Masculino , Arteria Femoral/cirugía , Presión Sanguínea/efectos de los fármacos , Electrocardiografía/métodos , Evaluación Preclínica de Medicamentos/métodosRESUMEN
Active sampling in the olfactory domain is a fundamental aspect of mouse behavior, and there is increasing evidence that respiration-entrained neural activity outside of the olfactory system sets an important global brain rhythm. It is therefore crucial to accurately measure breathing during natural behaviors. We develop a new approach to do this in freely moving animals, by implanting a telemetry-based pressure sensor into the right jugular vein, which allows for wireless monitoring of thoracic pressure. After verifying this technique against standard head-fixed respiration measurements, we combined it with EEG and EMG recording and used evolving partial coherence analysis to investigate the relationship between respiration and brain activity across a range of experiments in which the mice could move freely. During voluntary exploration of odors and objects, we found that the association between respiration and cortical activity in the delta and theta frequency range decreased, whereas the association between respiration and cortical activity in the alpha range increased. During sleep, however, the presentation of an odor was able to cause a transient increase in sniffing without changing dominant sleep rhythms (delta and theta) in the cortex. Our data align with the emerging idea that the respiration rhythm could act as a synchronizing scaffold for specific brain rhythms during wakefulness and exploration, but suggest that respiratory changes are less able to impact brain activity during sleep. Combining wireless respiration monitoring with different types of brain recording across a variety of behaviors will further increase our understanding of the important links between active sampling, passive respiration, and neural activity.NEW & NOTEWORTHY Animals can alter their respiration rate to actively sample their environment, and increasing evidence suggests that neurons across the brain align their firing to this changing rhythm. We developed a new approach to measure sniffing in freely moving mice while simultaneously recording brain activity, and uncovered how specific cortical rhythms changed their coherence with respiration rhythm during natural behaviors and across arousal states.
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Ratones Endogámicos C57BL , Respiración , Animales , Ratones , Masculino , Tecnología Inalámbrica/instrumentación , Electroencefalografía , Telemetría/instrumentación , Electromiografía , Vigilia/fisiología , Ondas Encefálicas/fisiología , Sueño/fisiologíaRESUMEN
OBJECTIVES: Atrial fibrillation (AF) is a common early arrhythmia after heart valve surgery that limits physical activity. We aimed to evaluate the criterion validity of the Apple Watch Series 5 single-lead electrocardiogram (ECG) for detecting AF in patients after heart valve surgery. DESIGN: We enrolled 105 patients from the University Hospital of North Norway, of whom 93 completed the study. All patients underwent single-lead ECG using the smartwatch three times or more daily on the second to third or third to fourth postoperative day. These results were compared with continuous 2-4 days ECG telemetry monitoring and a 12-lead ECG on the third postoperative day. RESULTS: On comparing the Apple Watch ECGs with the ECG monitoring, the sensitivity and specificity to detect AF were 91% (75, 100) and 96% (91, 99), respectively. The accuracy was 95% (91, 99). On comparing Apple Watch ECG with a 12-lead ECG, the sensitivity was 71% (62, 100) and the specificity was 92% (92, 100). CONCLUSION: The Apple smartwatch single-lead ECG has high sensitivity and specificity, and might be a useful tool for detecting AF in patients after heart valve surgery.
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Fibrilación Atrial , Frecuencia Cardíaca , Valor Predictivo de las Pruebas , Humanos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Masculino , Estudios Prospectivos , Femenino , Anciano , Persona de Mediana Edad , Reproducibilidad de los Resultados , Noruega , Factores de Tiempo , Aplicaciones Móviles , Resultado del Tratamiento , Electrocardiografía Ambulatoria/instrumentación , Telemetría/instrumentación , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Dispositivos Electrónicos Vestibles , Electrocardiografía , Válvulas Cardíacas/cirugía , Válvulas Cardíacas/fisiopatologíaRESUMEN
Aim: Patients with ischemic stroke (IS) commonly undergo monitoring to identify atrial fibrillation with mobile cardiac outpatient telemetry (MCOT) or implantable loop recorders (ILRs). The authors compared readmission, healthcare cost and survival in patients monitored post-stroke with either MCOT or ILR. Materials & methods: The authors used claims data from Optum's de-identified Clinformatics® Data Mart Database to identify patients with IS hospitalized from January 2017 to December 2020 who were prescribed ambulatory cardiac monitoring via MCOT or ILR. They compared the costs associated with the initial inpatient visit as well as the rate and causes of readmission, survival and healthcare costs over the following 18 months. Datasets were balanced using patient baseline and hospitalization characteristics. Multivariable generalized linear gamma regression was used for cost comparisons. Cox proportional hazard regression was used for survival and readmission analysis. Sub-cohorts were analyzed based on the severity of the index IS. Results: In 2244 patients, readmissions were significantly lower in the MCOT monitored group (30.2%) compared with the ILR group (35.4%) (hazard ratio [HR] 1.23; 95% CI: 1.04-1.46). Average cost over 18 months starting with the index IS was $27,429 (USD) lower in the MCOT group (95% CI: $22,353-$32,633). Survival difference bordered on statistical significance and trended to lower mortality in MCOT (8.9%) versus ILR (11.3%) (HR 1.30; 95% CI: 1:00-1.69), led by significance in patients with complications or comorbidities with the index event (MCOT 7.5%, ILR 11.5%; HR 1.62; 95% CI: 1.11-2.36). Conclusion: The use of MCOT versus ILR as the primary monitor following IS was associated with significant decreases in readmission, lower costs for the initial IS and total care over the next 18 months, significantly lower mortality for patients with complications and comorbidities at the index stroke, and a trend toward improved survival across all patients.
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Readmisión del Paciente , Telemetría , Humanos , Masculino , Femenino , Anciano , Telemetría/economía , Telemetría/métodos , Telemetría/instrumentación , Readmisión del Paciente/estadística & datos numéricos , Readmisión del Paciente/economía , Persona de Mediana Edad , Fibrilación Atrial/economía , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/mortalidad , Costos de la Atención en Salud/estadística & datos numéricos , Accidente Cerebrovascular/economía , Accidente Cerebrovascular/mortalidad , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular Isquémico/economía , Accidente Cerebrovascular Isquémico/diagnóstico , Accidente Cerebrovascular Isquémico/mortalidad , Estudios Retrospectivos , Anciano de 80 o más AñosRESUMEN
INTRODUCTION: Prolonged cardiac monitoring after cryptogenic stroke or embolic stroke of undetermined source (ESUS) is necessary to identify atrial fibrillation (AF) that requires anticoagulation. Wearable devices may improve AF detection compared to conventional management. We aimed to review the evidence for the use of wearable devices in post-cryptogenic stroke and post-ESUS monitoring. METHODS: We performed a systematic search of PubMed, EMBASE, Scopus and clinicaltrials.gov on 21 July 2022, identifying all studies that investigated the use of wearable devices in patients with cryptogenic stroke or ESUS. The outcomes of AF detection were analysed. Literature reports on electrocardiogram (ECG)-based (external wearable, handheld, patch, mobile cardiac telemetry [MCT], smartwatch) and photoplethysmography (PPG)-based (smartwatch, smartphone) devices were summarised. RESULTS: A total of 27 relevant studies were included (two randomised controlled trials, seven prospective trials, 10 cohort studies, six case series and two case reports). Only four studies compared wearable technology to Holter monitoring or implantable loop recorder, and these studies showed no significant differences on meta-analysis (odds ratio 2.35, 95% confidence interval [CI] 0.74-7.48, I 2 = 70%). External wearable devices detected AF in 20.7% (95% CI 14.9-27.2, I 2 = 76%) of patients and MCT detected new AF in 9.6% (95% CI 7.4%-11.9%, I 2 = 56%) of patients. Other devices investigated included patch sensors, handheld ECG recorders and PPG-based smartphone apps, which demonstrated feasibility in the post-cryptogenic stroke and post-ESUS setting. CONCLUSION: Wearable devices that are ECG or PPG based are effective for paroxysmal AF detection after cryptogenic stroke and ESUS, but further studies are needed to establish how they compare with Holter monitors and implantable loop recorder.
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Fibrilación Atrial , Accidente Cerebrovascular Embólico , Dispositivos Electrónicos Vestibles , Humanos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/complicaciones , Electrocardiografía/instrumentación , Electrocardiografía Ambulatoria/instrumentación , Accidente Cerebrovascular Embólico/etiología , Accidente Cerebrovascular Embólico/diagnóstico , Accidente Cerebrovascular Isquémico/diagnóstico , Accidente Cerebrovascular Isquémico/complicaciones , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Fotopletismografía/instrumentación , Telemetría/instrumentaciónRESUMEN
BACKGROUND: Conduction disturbances are a common complication of transcatheter aortic valve replacement (TAVR). Mobile Cardiac Telemetry (MCT) allows for continuous monitoring with near "real time" alerts and has allowed for timely detection of conduction abnormalities and pacemaker placement in small trials. A standardized, systematic approach utilizing MCT devices post TAVR has not been widely implemented, leading to variation in use across hospital systems. OBJECTIVES: Our aim was to evaluate the utility of a standardized, systematic approach utilizing routine MCT to facilitate safe and earlier discharge by identifying conduction disturbances requiring permanent pacemaker (PPM) placement. We also sought to assess the occurrence of actionable arrhythmias in post-TAVR patients. METHODS: Using guidance from the JACC Scientific Expert Panel, a protocol was implemented starting in December 2019 to guide PPM placement post-TAVR across our health system. All patients who underwent TAVR from December 2019 to June 2021 across four hospitals within Northwell Health, who did not receive or have a pre-existing PPM received an MCT device at discharge and were monitored for 30 days. Clinical and follow-up data were collected and compared to pre initiative patients. RESULTS: During the initiative 693 patients were monitored with MCT upon discharge, 21 of whom required PPM placement. Eight of these patients had no conduction abnormality on initial or discharge ECG. 59 (8.6 %) patients were found to have new atrial fibrillation or flutter via MCT monitoring. There were no adverse events in the initiative group. Prior to the initiative, 1281 patients underwent TAVR over a one-year period. The initiative group had significantly shorter length of stay than pre-initiative patients (2.5 ± 4.5 vs 3.0 ± 3.8 days, p < 0.001) and lower overall PPM placement rate within 30 days post-TAVR (16 % vs 20.5 %, P = 0.0125). CONCLUSIONS: In our study, implementation of a standardized, systematic approach utilizing MCT in post-TAVR patients was safe and allowed for timely detection of conduction abnormalities requiring pacemaker placement. This strategy also detected new atrial fibrillation and flutter. Reduction in post TAVR pacemaker rate and length of stay were also noted although this effect is multifactorial.
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Estenosis de la Válvula Aórtica , Válvula Aórtica , Arritmias Cardíacas , Estimulación Cardíaca Artificial , Marcapaso Artificial , Valor Predictivo de las Pruebas , Telemetría , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/instrumentación , Masculino , Femenino , Anciano de 80 o más Años , Anciano , Factores de Tiempo , Resultado del Tratamiento , Telemetría/instrumentación , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatología , Arritmias Cardíacas/terapia , Arritmias Cardíacas/etiología , Estenosis de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/fisiopatología , Válvula Aórtica/cirugía , Válvula Aórtica/fisiopatología , Factores de Riesgo , Atención Ambulatoria , Frecuencia Cardíaca , Estudios Retrospectivos , Alta del Paciente , Potenciales de AcciónAsunto(s)
Arritmias Cardíacas/diagnóstico , Efectos Adversos a Largo Plazo/cirugía , Psicotrópicos/efectos adversos , Telemetría/instrumentación , Adulto , Anciano , Arritmias Cardíacas/epidemiología , Estudios de Cohortes , Femenino , Humanos , Efectos Adversos a Largo Plazo/epidemiología , Masculino , Persona de Mediana Edad , Psicotrópicos/uso terapéutico , Telemetría/métodos , Telemetría/estadística & datos numéricosRESUMEN
Repeated head impact exposure and concussions are common in American football. Identifying the factors associated with high magnitude impacts aids in informing sport policy changes, improvements to protective equipment, and better understanding of the brain's response to mechanical loading. Recently, the Stanford Instrumented Mouthguard (MiG2.0) has seen several improvements in its accuracy in measuring head kinematics and its ability to correctly differentiate between true head impact events and false positives. Using this device, the present study sought to identify factors (e.g., player position, helmet model, direction of head acceleration, etc.) that are associated with head impact kinematics and brain strain in high school American football athletes. 116 athletes were monitored over a total of 888 athlete exposures. 602 total impacts were captured and verified by the MiG2.0's validated impact detection algorithm. Peak values of linear acceleration, angular velocity, and angular acceleration were obtained from the mouthguard kinematics. The kinematics were also entered into a previously developed finite element model of the human brain to compute the 95th percentile maximum principal strain. Overall, impacts were (mean ± SD) 34.0 ± 24.3 g for peak linear acceleration, 22.2 ± 15.4 rad/s for peak angular velocity, 2979.4 ± 3030.4 rad/s2 for peak angular acceleration, and 0.262 ± 0.241 for 95th percentile maximum principal strain. Statistical analyses revealed that impacts resulting in Forward head accelerations had higher magnitudes of peak kinematics and brain strain than Lateral or Rearward impacts and that athletes in skill positions sustained impacts of greater magnitude than athletes in line positions. 95th percentile maximum principal strain was significantly lower in the observed cohort of high school football athletes than previous reports of collegiate football athletes. No differences in impact magnitude were observed in athletes with or without previous concussion history, in athletes wearing different helmet models, or in junior varsity or varsity athletes. This study presents novel information on head acceleration events and their resulting brain strain in high school American football from our advanced, validated method of measuring head kinematics via instrumented mouthguard technology.
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Traumatismos en Atletas/fisiopatología , Encéfalo/fisiología , Traumatismos Craneocerebrales/fisiopatología , Protectores Bucales , Equipo Deportivo , Telemetría/instrumentación , Adolescente , Fenómenos Biomecánicos , Fútbol Americano , Cabeza , Humanos , Masculino , Instituciones Académicas , Estados Unidos , Dispositivos Electrónicos VestiblesRESUMEN
Applications on electromagnetic waves in the field of biotelemetry have increased in the latest years, being used to prevent, diagnose, and treatment of several diseases. In this context, biotelemetry allows minimally invasive monitoring of the physiologic, improving comfort and patient care and significantly reducing hospital costs. Aiming to assist the mineral bone density classification, through a radio frequency signal (RF), for a later diagnosis of osteoporosis, Osseus was proposed in 2018. This equipment is a combination of the application of techniques and concepts of several areas such as software, electrical, electronic, computational, and biomedical engineering, developed at a low cost, with easy access to the population, and non-invasive. However, when placed on evaluation, potential improvements were identified to increase the stability of Osseus operation. It is proposed the implementation of improvements in the antennas used by Osseus, aiming its miniaturization, improvement in the reception of the RF signal, and better stability of the equipment's operation. Then, two antennas were built, one of which was used as a project for the second, which is an array. The array showed significant improvements in the radiation parameters relevant to the application, being a candidate to replace the antennas currently in use at Osseus.
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Tamizaje Masivo/instrumentación , Osteoporosis/diagnóstico , Telemetría/instrumentación , Dispositivos Electrónicos Vestibles , Ingeniería Biomédica , Densidad Ósea , Campos Electromagnéticos , Diseño de Equipo , Humanos , Tamizaje Masivo/métodos , Miniaturización , Programas Informáticos , Telemetría/métodosRESUMEN
Instrumented mouthpieces (IM) offer a means of measuring head impacts that occur in sport. Direct measurement of angular head kinematics is preferential for accuracy; however, existing IMs measure angular velocity and differentiate the measurement to calculate angular acceleration, which can limit bandwidth and consume more power. This study presents the development and validation of an IM that uses new, low-power accelerometers for direct measurement of linear and angular acceleration over a broad range of head impact conditions in American football. IM sensor accuracy for measuring six-degree-of-freedom head kinematics was assessed using two helmeted headforms instrumented with a custom-fit IM and reference sensor instrumentation. Head impacts were performed at 10 locations and 6 speeds representative of the on-field conditions associated with injurious and non-injurious impacts in American football. Sensor measurements from the IM were highly correlated with those from the reference instrumentation located at the maxilla and skull center of gravity. Based on pooled data across headform and impact location, R2 ≥ 0.94, mean absolute error (AE) ≤ 7%, and mean relative impact angle ≤ 11° for peak linear and angular acceleration and angular velocity while R2 ≥ 0.90 and mean AE ≤ 7% for kinematic-based injury metrics used in helmet tests.
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Fútbol Americano , Protectores Bucales , Equipo Deportivo , Aceleración , Fenómenos Biomecánicos , Diseño de Equipo , Cabeza/fisiología , Humanos , Telemetría/instrumentación , Estados Unidos , Dispositivos Electrónicos VestiblesRESUMEN
Wearable devices have been shown to effectively measure the head's movement during impacts in sports like American football. When a head impact occurs, the device is triggered to collect and save the kinematic measurements during a predefined time window. Then, based on the collected kinematics, finite element (FE) head models can calculate brain strain and strain rate, which are used to evaluate the risk of mild traumatic brain injury. To find a time window that can provide a sufficient duration of kinematics for FE analysis, we investigated 118 on-field video-confirmed football head impacts collected by the Stanford Instrumented Mouthguard. The simulation results based on the kinematics truncated to a shorter time window were compared with the original to determine the minimum time window needed for football. Because the individual differences in brain geometry influence these calculations, we included six representative brain geometries and found that larger brains need a longer time window of kinematics for accurate calculation. Among the different sizes of brains, a pre-trigger time of 40 ms and a post-trigger time of 70 ms were found to yield calculations of brain strain and strain rate that were not significantly different from calculations using the original 200 ms time window recorded by the mouthguard. Therefore, approximately 110 ms is recommended for complete modeling of impacts for football.
Asunto(s)
Encéfalo/fisiología , Fútbol Americano/lesiones , Modelos Biológicos , Telemetría/métodos , Aceleración , Traumatismos en Atletas/fisiopatología , Fenómenos Biomecánicos , Lesiones Encefálicas/fisiopatología , Femenino , Análisis de Elementos Finitos , Cabeza , Humanos , Masculino , Protectores Bucales , Equipo Deportivo , Telemetría/instrumentación , Estados Unidos , Dispositivos Electrónicos VestiblesRESUMEN
Most alphaviruses are mosquito-borne and can cause severe disease in humans and domesticated animals. In North America, eastern equine encephalitis virus (EEEV) is an important human pathogen with case fatality rates of 30-90%. Currently, there are no therapeutics or vaccines to treat and/or prevent human infection. One critical impediment in countermeasure development is the lack of insight into clinically relevant parameters in a susceptible animal model. This study examined the disease course of EEEV in a cynomolgus macaque model utilizing advanced telemetry technology to continuously and simultaneously measure temperature, respiration, activity, heart rate, blood pressure, electrocardiogram (ECG), and electroencephalography (EEG) following an aerosol challenge at 7.0 log10 PFU. Following challenge, all parameters were rapidly and substantially altered with peak alterations from baseline ranged as follows: temperature (+3.0-4.2°C), respiration rate (+56-128%), activity (-15-76% daytime and +5-22% nighttime), heart rate (+67-190%), systolic (+44-67%) and diastolic blood pressure (+45-80%). Cardiac abnormalities comprised of alterations in QRS and PR duration, QTc Bazett, T wave morphology, amplitude of the QRS complex, and sinoatrial arrest. An unexpected finding of the study was the first documented evidence of a critical cardiac event as an immediate cause of euthanasia in one NHP. All brain waves were rapidly (~12-24 hpi) and profoundly altered with increases of up to 6,800% and severe diffuse slowing of all waves with decreases of ~99%. Lastly, all NHPs exhibited disruption of the circadian rhythm, sleep, and food/fluid intake. Accordingly, all NHPs met the euthanasia criteria by ~106-140 hpi. This is the first of its kind study utilizing state of the art telemetry to investigate multiple clinical parameters relevant to human EEEV infection in a susceptible cynomolgus macaque model. The study provides critical insights into EEEV pathogenesis and the parameters identified will improve animal model development to facilitate rapid evaluation of vaccines and therapeutics.
Asunto(s)
Infecciones por Alphavirus/virología , Modelos Animales de Enfermedad , Electroencefalografía , Virus de la Encefalitis Equina del Este , Monitoreo Fisiológico/instrumentación , Telemetría/instrumentación , Aerosoles , Infecciones por Alphavirus/patología , Animales , Presión Sanguínea , Temperatura Corporal , Chlorocebus aethiops , Femenino , Frecuencia Cardíaca , Humanos , Macaca fascicularis , Masculino , Monitoreo Fisiológico/métodos , Actividad Motora , Fenómenos Fisiológicos Respiratorios , Telemetría/métodos , Células VeroRESUMEN
Implantable telemetric transponders for contactless measurement of physiological parameters are often used in animal-based research. After explantation, single-use devices cannot be re-implanted because of non-validated functionality and necessary re-sterilisation. This is disadvantageous because the battery life would enable a second implantation cycle in another animal. To save costs and time taken for the manufacturer's refurbishing process, we validated and implemented a re-sterilisation protocol for single-use transponders using hydrogen peroxide gas. The described protocol was established with models, i.e., for large (n = 7) and small (n = 3) animals, of telemetric device from 2 different manufacturers (Data Science International and EMKA). All transponders, prepared according to the protocol, were previously implanted subcutaneously in the flank of pigs or rats for a duration of 21 days. Our investigations demonstrate that disinfection only is not sufficient against bacterial contamination and that sterility can only be achieved by additional gas sterilisation with hydrogen peroxide. Furthermore, re-implantation of the re-sterilised transponders into pigs caused neither undesired tissue reactions along the transponder nor impairment of the measured values when compared to the first implantation and after necropsy in 4 cases. We were able to demonstrate that, using our protocol, re-implantation of reprocessed single-use telemetric devices can be performed without compromising transponder quality.
Asunto(s)
Equipo Reutilizado , Peróxido de Hidrógeno , Esterilización , Telemetría/instrumentación , Animales , Prótesis e Implantes , Ratas , PorcinosRESUMEN
Impacts to the back of the head due to rearward falls, also referred to as "backfall" events, represent a common source of TBI for athletes and soldiers. A new experimental apparatus is described for replicating the linear and rotational kinematics of the head during backfall events. An anthropomorphic test device (ATD) with a head-borne sensor suite was configured to fall backwards from a standing height, inducing contact between the rear of the head and a ground surface simulant. A pivoting swing arm and release strap were used to generate consistent and realistic head kinematics. Backfall experiments were performed with the ATD fitted with an American football helmet and the resulting linear and rotational head kinematics, as well as calculated injury metrics, compared favorably with those of football players undergoing similar impacts during games or play reconstructions. This test method complements existing blunt impact helmet performance experiments, such as drop tower and pneumatic ram test methods, which may not be able to fully reproduce head-neck-torso kinematics during a backfall event.