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Lee, D., Nowinski, D. & Augustine, R. (2018). A UWB sensor based on resistively-loaded dipole antenna for skull healing on cranial surgery phantom models. Microwave and optical technology letters (Print), 60(4), 897-905
Open this publication in new window or tab >>A UWB sensor based on resistively-loaded dipole antenna for skull healing on cranial surgery phantom models
2018 (English)In: Microwave and optical technology letters (Print), ISSN 0895-2477, E-ISSN 1098-2760, Vol. 60, no 4, p. 897-905Article in journal (Refereed) Published
Abstract [en]

After craniotomy, the monitoring of the skull healing progression is strongly needed to take a proper medical intervention. The CT scans is however currently used for follow-up after craniotomy resulting in lack of an effective and safety problem. This research proposes an alternative for monitoring the skull healing using ultra-wide band (UWB) antenna. For the healing of the skull surgical defect, a compact resistively-loaded dipole antenna is designed and analyzed in terms of its performance in the time domain. The head phantoms having a wideband characteristic are fabricated and used as models for the skull healing process. To represent various mineralization stages, phantoms with various dielectric constants from hydrogel scaffold to the normal skull and their intermediate values are used. The UWB radar technique in the time domain is implemented in the healing process of skull injuries emulating cranial cavities that are made as part of craniosynostosis treatment. The measurement results at the defect area show that the variations in amplitude of the reflected pulse as the skull healing is progressed. The results obtained can contribute to the development of microwave-based techniques as a preliminary study of a proof concept before clinical trial in the healing process after cranial surgery.

Place, publisher, year, edition, pages
WILEY, 2018
Keywords
craniotomy, craniosynostosis, resistively-loaded dipole antenna, ultra-wideband (UWB) antennas
National Category
Surgery Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-350741 (URN)10.1002/mop.31077 (DOI)000426868400018 ()
Available from: 2018-05-16 Created: 2018-05-16 Last updated: 2018-06-05Bibliographically approved
Raaben, M., Redzwan, S., Augustine, R. & Blokhuis, T. J. (2018). COMplex Fracture Orthopedic Rehabilitation (COMFORT) - Real-time visual biofeedback on weight bearing versus standard training methods in the treatment of proximal femur fractures in the elderly: study protocol for a multicenter randomized controlled trial. Trials, 19, Article ID 220.
Open this publication in new window or tab >>COMplex Fracture Orthopedic Rehabilitation (COMFORT) - Real-time visual biofeedback on weight bearing versus standard training methods in the treatment of proximal femur fractures in the elderly: study protocol for a multicenter randomized controlled trial
2018 (English)In: Trials, ISSN 1745-6215, E-ISSN 1745-6215, Vol. 19, article id 220Article in journal (Refereed) Published
Abstract [en]

Background:

Proximal femur fractures are a common injury after low energy trauma in the elderly. Most rehabilitation programs are based on restoring mobility and early resumption of weight-bearing. However, therapy compliance is low in patients following lower extremity fractures. Moreover, little is known about the relevance of gait parameters and how to steer the rehabilitation after proximal femur fractures in the elderly. Therefore, the aim of this prospective, randomized controlled trial is to gain insight in gait parameters and evaluate if real-time visual biofeedback can improve therapy compliance after proximal femur fractures in the elderly.

Methods:

This is a two-arm, parallel-design, prospective, randomized controlled trial. Inclusion criteria are age >= 60 years, a proximal femur fracture following low energy trauma, and unrestricted-weight bearing. Exclusion criteria are cognitive impairment and limited mobility before trauma. Participants are randomized into either the control group, which receives care as usual, or the intervention group, which receives real-time visual biofeedback about weight-bearing during gait in addition to care as usual. Spatiotemporal gait parameters will be measured in 94 participants per group during a 30-m walk with an ambulatory biofeedback system (SensiStep). The progress of rehabilitation will be evaluated by the primary outcome parameters maximum peak load and step duration in relation to the discharge date. Secondary outcome parameters include other spatiotemporal gait parameters in relation to discharge date. Furthermore, the gait parameters will be related to three validated clinical tests: Elderly Mobility Scale; Functional Ambulation Categories; and Visual Analogue Scale. The primary hypothesis is that participants in the intervention group will show improved and faster rehabilitation compared to the control group.

Discussion:

The first aim of this multicenter trial is to investigate the normal gait patterns after proximal femur fractures in the elderly. The use of biofeedback systems during rehabilitation after proximal femur fractures in the elderly is promising; therefore, the second aim is to investigate the effect of real-time visual biofeedback on gait after proximal femur fractures in the elderly. This could lead to improved outcome. In addition, analysis of the population may indicate characteristics of subgroups that benefit from feedback, making a differentiated approach in rehabilitation strategy possible.

Keywords
Proximal femur fracture, Weight-bearing, Biofeedback, Gait analysis, SensiStep, Fracture rehabilitation
National Category
Orthopaedics Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-353203 (URN)10.1186/s13063-018-2612-9 (DOI)000429992800001 ()29650034 (PubMedID)
Available from: 2018-06-13 Created: 2018-06-13 Last updated: 2018-06-14Bibliographically approved
Raaben, M., Holtslag, H. R., Leenen, L. P. H., Augustine, R. & Blokhuis, T. J. (2018). Real-time visual biofeedback during weight bearing improves therapy compliance in patients following lower extremity fractures. Gait & Posture, 59, 206-210
Open this publication in new window or tab >>Real-time visual biofeedback during weight bearing improves therapy compliance in patients following lower extremity fractures
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2018 (English)In: Gait & Posture, ISSN 0966-6362, E-ISSN 1879-2219, Vol. 59, p. 206-210Article in journal (Refereed) Published
Abstract [en]

Background: Individuals with lower extremity fractures are often instructed on how much weight to bear on the affected extremity. Previous studies have shown limited therapy compliance in weight bearing during rehabilitation. In this study we investigated the effect of real-time visual biofeedback on weight bearing in individuals with lower extremity fractures in two conditions: full weight bearing and touch-down weight bearing. Methods: 11 participants with full weight bearing and 12 participants with touch-down weight bearing after lower extremity fractures have been measured with an ambulatory biofeedback system. The participants first walked 15 m and the biofeedback system was only used to register the weight bearing. The same protocol was then repeated with real-time visual feedback during weight bearing. The participants could thereby adapt their loading to the desired level and improve therapy compliance. Results: In participants with full weight bearing, real-time visual biofeedback resulted in a significant increase in loading from 50.9 +/- 7.51% bodyweight (BW) without feedback to 63.2 +/- 6.74% BW with feedback (P=0.0016). In participants with touch-down weight bearing, the exerted lower extremity load decreased from 16.7 +/- 9.77 kg without feedback to 10.27 +/- 4.56 kg with feedback (P=0.0718). More important, the variance between individual steps significantly decreased after feedback (P=0.018). Conclusions: Ambulatory monitoring weight bearing after lower extremity fractures showed that therapy compliance is low, both in full and touch-down weight bearing. Real-time visual biofeedback resulted in significantly higher peak loads in full weight bearing and increased accuracy of individual steps in touch-down weight bearing. Real-time visual biofeedback therefore results in improved therapy compliance after lower extremity fractures.

Place, publisher, year, edition, pages
ELSEVIER IRELAND LTD, 2018
Keywords
SensiStep, Gait monitoring, Biofeedback, Lower extremity, Weight-bearing
National Category
Orthopaedics Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-342648 (URN)10.1016/j.gaitpost.2017.10.022 (DOI)000415235300037 ()29078134 (PubMedID)
Available from: 2018-02-28 Created: 2018-02-28 Last updated: 2018-03-08Bibliographically approved
Asan, N. B., Carlos, P. P., Redzwan, S., Noreland, D., Hassan, E., Rydberg, A., . . . Augustine, R. (2017). Data Packet Transmission through Fat Tissue for Wireless Intra-Body Networks. IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology
Open this publication in new window or tab >>Data Packet Transmission through Fat Tissue for Wireless Intra-Body Networks
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2017 (English)In: IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology, ISSN 2469-7249Article in journal (Refereed) Epub ahead of print
Abstract [en]

This work explores high data rate microwave communication through fat tissue in order to address the wide bandwidth requirements of intra-body area networks. We have designed and carried out experiments on an IEEE 802.15.4 based WBAN prototype by measuring the performance of the fat tissue channel in terms of data packet reception with respect to tissue length and power transmission. This paper proposes and demonstrates a high data rate communication channel through fat tissue using phantom and ex-vivo environments. Here, we achieve a data packet reception of approximately 96 % in both environments. The results also show that the received signal strength drops by ~1 dBm per 10 mm in phantom and ~2 dBm per 10 mm in ex-vivo. The phantom and ex-vivo experimentations validated our approach for high data rate communication through fat tissue for intrabody network applications. The proposed method opens up new opportunities for further research in fat channel communication. This study will contribute to the successful development of high bandwidth wireless intra-body networks that support high data rate implanted, ingested, injected, or worn devices

Keywords
Intra-body communication, microwave, channel characterization, data packet, Software Defined Radio, GNU Radio, exvivo, phantom
National Category
Engineering and Technology Medical and Health Sciences
Identifiers
urn:nbn:se:uu:diva-335351 (URN)10.1109/JERM.2017.2766561 (DOI)
Projects
Eurostars project under Grant E-9655-COMFORTSwedish Vinnova project under Grant BDAS (2015-04159)Swedish Vinnova project under Reliable, interoperable and secure communication for body network (2017-03568)
Funder
eSSENCE - An eScience CollaborationVINNOVA, 2015-04159VINNOVA, 2017-03568
Available from: 2017-12-04 Created: 2017-12-04 Last updated: 2017-12-05Bibliographically approved
Asan, N. B., Redzwan, S., Rydberg, A., Augustine, R., Noreland, D., Hassan, E. & Voigt, T. (2017). Human fat tissue: A microwave communication channel. In: Proc. 1st MTT-S International Microwave Bio Conference: . Paper presented at IMBIOC 2017, May 15–17, Gothenburg, Sweden. IEEE
Open this publication in new window or tab >>Human fat tissue: A microwave communication channel
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2017 (English)In: Proc. 1st MTT-S International Microwave Bio Conference, IEEE, 2017Conference paper, Published paper (Refereed)
Abstract [en]

In this paper, we present an approach for communication through human body tissue in the R-band frequency range. This study examines the ranges of microwave frequencies suitable for intra-body communication. The human body tissues are characterized with respect to their transmission properties using simulation modeling and phantom measurements. The variations in signal coupling with respect to different tissue thicknesses are studied. The simulation and phantom measurement results show that electromagnetic communication in the fat layer is viable with attenuation of approximately 2 dB per 20 mm. 

Place, publisher, year, edition, pages
IEEE, 2017
Keywords
tissue characterization, transmission medium, biomedical sensor, channel model, phantom measurement
National Category
Medical Engineering
Identifiers
urn:nbn:se:uu:diva-335479 (URN)10.1109/IMBIOC.2017.7965801 (DOI)978-1-5386-1713-7 (ISBN)
Conference
IMBIOC 2017, May 15–17, Gothenburg, Sweden
Projects
Eurostars project (grant E-9655-COMFORT)Swedish Vinnova project (grant BDAS)eSSENCE
Available from: 2017-07-03 Created: 2017-12-05 Last updated: 2017-12-30Bibliographically approved
Asan, N. B., Noreland, D., Hassan, E., Redzwan, S., Rydberg, A., Blokhuis, T. J., . . . Augustine, R. (2017). Intra-body microwave communication through adipose tissue. Healthcare Technology Letters, 4(4), 115-121
Open this publication in new window or tab >>Intra-body microwave communication through adipose tissue
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2017 (English)In: Healthcare Technology Letters, E-ISSN 2053-3713, Vol. 4, no 4, p. 115-121Article in journal (Refereed) Published
National Category
Medical Engineering
Identifiers
urn:nbn:se:uu:diva-334322 (URN)10.1049/htl.2016.0104 (DOI)000408370500001 ()28868147 (PubMedID)
Projects
eSSENCE
Available from: 2017-05-23 Created: 2017-11-22 Last updated: 2017-12-30Bibliographically approved
Lee, D., Augustine, R. & Nowinski, D. (2017). Investigation of Skull Defect using Resistive Dipole Antenna on Cranial Surgery Phantom Model. In: 2017 IEEE Conference on Antenna Measurements & Applications (Cama): . Paper presented at IEEE Conference on Antenna Measurements and Applications (CAMA), DEC 04-06, 2017, Tsukuba, JAPAN (pp. 301-303). IEEE
Open this publication in new window or tab >>Investigation of Skull Defect using Resistive Dipole Antenna on Cranial Surgery Phantom Model
2017 (English)In: 2017 IEEE Conference on Antenna Measurements & Applications (Cama), IEEE, 2017, p. 301-303Conference paper, Published paper (Other academic)
Abstract [en]

In this work, the resistive dipole antenna is designed for sensing the effective dielectric constants of the skull defect as part of the healing stages for craniosynostosis. The performance of the fabricated resistive dipole antenna is analyzed by comparing to the conventional dipole antenna in terms of both frequency and time domain. The measurement result is shown that the amplitude of the reflected pulse is increased as the thickness of the powder is increased.

Place, publisher, year, edition, pages
IEEE, 2017
Series
IEEE Conference on Antenna Measurements & Applications, ISSN 2474-1760
Keywords
craniotomy, craniosynostosis, effective dielectric constant, microwaves, resistive antenna
National Category
Medical Engineering
Identifiers
urn:nbn:se:uu:diva-350700 (URN)10.1109/CAMA.2017.8273432 (DOI)000425256200085 ()978-1-5090-5028-4 (ISBN)
Conference
IEEE Conference on Antenna Measurements and Applications (CAMA), DEC 04-06, 2017, Tsukuba, JAPAN
Available from: 2018-05-17 Created: 2018-05-17 Last updated: 2018-05-17Bibliographically approved
Augustine, R., Kurup, D. G., Redzwan, S., Mathur, P., Raman, S., Lee, D. & Kim, K. (2017). Microwave reflectivity analysis of bone mineral density using ultra wide band antenna. Microwave and optical technology letters (Print), 59(1), 21-26
Open this publication in new window or tab >>Microwave reflectivity analysis of bone mineral density using ultra wide band antenna
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2017 (English)In: Microwave and optical technology letters (Print), ISSN 0895-2477, E-ISSN 1098-2760, Vol. 59, no 1, p. 21-26Article in journal (Refereed) Published
Abstract [en]

In this paper, an approach to analyze the bone mineral density (BMD) based on microwave reflectivity is presented The proposed method enables us to overcome the health risks associated with diagnostic techniques such as X-rays for repeated study of the rate of mineralization in the case of fractures or de-mineralization in the case of osteoporosis. The proposed method is used to demonstrate the application of microwaves for continuous observation of skull healing process during post-cranial surgery period. The proposed technique can be a potential clinical model in future for extracting target characteristics such as bone deposition thickness and other cranial defects. Based on the conclusions of wideband measured data and signal processing techniques, we propose to design the Transceiver using ultra-wideband (UWB) pulsed technology.

Keywords
bone mineral density, osteoporosis, microwave reflectivity
National Category
Medical Biotechnology Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-312031 (URN)10.1002/mop.30210 (DOI)000389132600007 ()
Funder
Stiftelsen Olle Engkvist Byggmästare
Available from: 2017-01-05 Created: 2017-01-04 Last updated: 2017-11-29Bibliographically approved
Perez, M. D., Redzwan, S. M., Velander, J., Raaben, M., Asan, N. B., Blokhuis, T. & Augustine, R. (2017). Microwave Sensors for New Approach in Monitoring Hip Fracture Healing. In: 2017 11th European Conference On Antennas And Propagation (EUCAP): . Paper presented at 11th European Conference on Antennas and Propagation (EUCAP), MAR 19-24, 2017, Paris, FRANCE (pp. 1838-1842). IEEE
Open this publication in new window or tab >>Microwave Sensors for New Approach in Monitoring Hip Fracture Healing
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2017 (English)In: 2017 11th European Conference On Antennas And Propagation (EUCAP), IEEE , 2017, p. 1838-1842Conference paper, Published paper (Refereed)
Abstract [en]

Cyber-Physical System (CPS) applications in lower-extremity bony-fracture rehabilitation systems require real-time biophysical data. Emerging and interesting solutions are microwave approaches that provide good contrast between hard and soft tissues and between local anomalies inside tissues. Preliminarily some contacting non-invasive planar methods have been investigated in their feasibility of detecting human tissues variations with promising results. In this work we introduce two new microwave planar sensors for a new approach of hip fracture healing follow-up tool. They are designed for improved resolution and penetration at frequencies between 1 to 3 GHz in detecting variations in bone, muscle or fat tissues that are expected during a rehabilitation process. The resonant devices are optimized using Frequency Domain Reflectometry and CST (R) environment and validated using clinical trials with volunteers. The new approach is validated using clinical trials with volunteers and patients. These outcomes further emphasize the feasibility of devising systems for fracture rehabilitation.

Place, publisher, year, edition, pages
IEEE, 2017
Series
Proceedings of the European Conference on Antennas and Propagation, ISSN 2164-3342
Keywords
microwave, biosensor, measurement, fracture rehabilitation
National Category
Medical Engineering
Identifiers
urn:nbn:se:uu:diva-333846 (URN)000403827301188 ()978-8-8907-0187-0 (ISBN)
Conference
11th European Conference on Antennas and Propagation (EUCAP), MAR 19-24, 2017, Paris, FRANCE
Available from: 2017-11-22 Created: 2017-11-22 Last updated: 2017-11-22Bibliographically approved
Asan, N. B., Velander, J., Redzwan, S., Augustine, R., Hassan, E., Noreland, D., . . . Blokhuis, T. J. (2017). Reliability of the fat tissue channel for intra-body microwave communication. In: 2017 IEEE Conference on Antenna Measurements & Applications (CAMA): . Paper presented at IEEE Conference on Antenna Measurements and Applications (CAMA), Tsukuba, Japan, December 04-06, 2017 (pp. 310-313). IEEE
Open this publication in new window or tab >>Reliability of the fat tissue channel for intra-body microwave communication
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2017 (English)In: 2017 IEEE Conference on Antenna Measurements & Applications (CAMA), IEEE, 2017, p. 310-313Conference paper, Published paper (Refereed)
Abstract [en]

Recently, the human fat tissue has been proposed as a microwave channel for intra-body sensor applications. In this work, we assess how disturbances can prevent reliable microwave propagation through the fat channel. Perturbants of different sizes are considered. The simulation and experimental results show that efficient communication through the fat channel is possible even in the presence of perturbants such as embedded muscle layers and blood vessels. We show that the communication channel is not affected by perturbants that are smaller than 15 mm cube.

Place, publisher, year, edition, pages
IEEE, 2017
Series
IEEE Conference on Antenna Measurements & Applications, E-ISSN 2474-1760
Keywords
microwaves, dielectric properties, fat channel, intra-body communication, phantom
National Category
Medical Engineering Computer Sciences
Identifiers
urn:nbn:se:uu:diva-335483 (URN)10.1109/CAMA.2017.8273435 (DOI)000425256200088 ()978-1-5090-5028-4 (ISBN)
Conference
IEEE Conference on Antenna Measurements and Applications (CAMA), Tsukuba, Japan, December 04-06, 2017
Funder
VINNOVA, 2015-04159
Available from: 2017-12-05 Created: 2017-12-05 Last updated: 2018-05-17Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-2876-223X

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