Microwave Bone Imaging: A Preliminary Investigation on Numerical Bone Phantoms for Bone Health Monitoring

Amin, Bilal; Shahzad, Atif; O’Halloran, Martin; Elahi, Muhammad Adnan

doi:10.3390/s20216320

Cited by 17 publications

(13 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is mainly because of the heterogeneity of tissue layers that exhibits more attenuation than the homogeneous layers [ 71 ]. Because of the heterogeneous nature of biological tissues, the electromagnetic field distribution is complicated and depends on a variety of factors, including the dielectric characteristics of each tissue and the existence of several interfaces (e.g., air/tissue and tissue/tissue) [ 70 , 72 ]. Moreover, the reflected and transmitted energy of the EM wave through surfaces between various tissues is determined by the relative permittivity, conductivity, and frequency [ 72 ].…”

Section: Resultsmentioning

confidence: 99%

“…Because of the heterogeneous nature of biological tissues, the electromagnetic field distribution is complicated and depends on a variety of factors, including the dielectric characteristics of each tissue and the existence of several interfaces (e.g., air/tissue and tissue/tissue) [ 70 , 72 ]. Moreover, the reflected and transmitted energy of the EM wave through surfaces between various tissues is determined by the relative permittivity, conductivity, and frequency [ 72 ]. The electrical properties of considered tissue (skin, fat and muscle) reported after Gabriel et al [ 73 ] and listed in Table 4 , were considered for discussion purposes.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

An Ex Vivo Study of Wireless Linkage Distance between Implantable LC Resonance Sensor and External Readout Coil

Farooq

Amin

Kraśny

et al. 2022

Sensors

Self Cite

View full text Add to dashboard Cite

The wireless monitoring of key physiological parameters such as heart rate, respiratory rate, temperature, and pressure can aid in preventive healthcare, early diagnosis, and patient-tailored treatment. In wireless implantable sensors, the distance between the sensor and the reader device is prone to be influenced by the operating frequency, as well as by the medium between the sensor and the reader. This manuscript presents an ex vivo investigation of the wireless linkage between an implantable sensor and an external reader for medical applications. The sensor was designed and fabricated using a cost-effective and accessible fabrication process. The sensor is composed of a circular planar inductor (L) and a circular planar capacitor (C) to form an inductor–capacitor (LC) resonance tank circuit. The reader system comprises a readout coil and data acquisition instrumentation. To investigate the effect of biological medium on wireless linkage, the readout distance between the sensor and the readout coil was examined independently for porcine and ovine tissues. In the bench model, to mimic the bio-environment for the investigation, skin, muscle, and fat tissues were used. The relative magnitude of the reflection coefficient (S11) at the readout coil was used as a metric to benchmark wireless linkage. A readable linkage signal was observed on the readout coil when the sensor was held up to 2.5 cm under layers of skin, muscle, and fat tissue. To increase the remote readout distance of the LC sensor, the effect of the repeater coil was also investigated. The experimental results showed that the magnitude of the reflection coefficient signal was increased 3–3.5 times in the presence of the repeater coil, thereby increasing the signal-to-noise ratio of the detected signal. Therefore, the repeater coil between the sensor and the readout coil allows a larger sensing range for a variety of applications in implanted or sealed fields.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

An Ex Vivo Study of Wireless Linkage Distance between Implantable LC Resonance Sensor and External Readout Coil

Farooq

Amin

Kraśny

et al. 2022

Sensors

Self Cite

View full text Add to dashboard Cite

show abstract

“…Over the last decades, microwave sensing and imaging has been investigated as a novel diagnostic technique, as it is a low health-risk method due to the application of nonionizing, low-power electromagnetic signals in the frequency range of hundreds of megahertz to a few gigahertz [ 17 , 18 ]. Microwave imaging has been used in medical applications, including the imaging of breast cancer [ 19 ], axillary lymph nodes [ 20 , 21 , 22 ], brain strokes [ 23 , 24 ] and bones [ 25 ]. These medical applications have justified the study of dielectric properties of many biological tissues, including liver [ 26 ], breast [ 27 , 28 ] among many others [ 29 , 30 ], and have triggered classification based studies [ 31 , 32 , 33 , 34 , 35 , 36 ].…”

Section: Introductionmentioning

confidence: 99%

Dielectric Characterization of Healthy Human Teeth from 0.5 to 18 GHz with an Open-Ended Coaxial Probe

Berezhanska

Godinho

Maló³

et al. 2023

Sensors

View full text Add to dashboard Cite

Dental caries is a major oral health issue which compromises oral health, as it is the main cause of oral pain and tooth loss. Early caries detection is essential for effective clinical intervention. However, methods commonly employed for its diagnosis often fail to detect early caries lesions, which motivates the research for more effective diagnostic solutions. In this work, the relative permittivity of healthy permanent teeth, in caries-prone areas, was studied between 0.5 and 18 GHz. The reliability of such measurements is an important first step to, ultimately, evaluate the feasibility of a microwave device for caries detection. The open-ended coaxial probe technique was employed. Its performance showed to be compromised by the poor probe-tooth contact. We proposed a method based on applying coupling media to reduce this limitation. A decrease in the measured relative permittivity variability was observed when the space between the probe tip and tooth surface was filled by coupling media instead of air. The influence of the experimental conditions in the measurement result was found to be less than 5%. Measurements conducted in ex vivo teeth showed that the relative permittivity of the dental crown and root ranges between 10.0–11.0 and 8.0–9.5, respectively.

show abstract

“…While MWI has been proposed to monitor osteoporosis based on the dielectric contrast between healthy and diseased human trabecular bones [9], [10], [22], no dedicated MWI system has been developed to measure in vivo dielectric properties of human bone in the microwave frequency range. To date, only two studies have measured in vivo dielectric properties of the human trabecular bones.…”

Section: Introductionmentioning

confidence: 99%

Experimental Validation of Microwave Imaging Prototype and DBIM-IMATCS Algorithm for Bone Health Monitoring

et al. 2022

Self Cite

View full text Add to dashboard Cite

The evaluation of the microwave imaging (MWI) prototype and imaging algorithms on experimental bone phantoms is a precursor step before clinical testing for measuring in vivo dielectric properties of human bones. To this end, this paper presents microwave tomographic image reconstruction of experimental phantoms of normal and diseased human calcaneus bone using an MWI prototype and distorted Born iterative method (DBIM) algorithm for bone health monitoring application. A two-layered simplified cylindrical-shaped 3-D printed phantom was used to mimic the human calcaneus bone. The external and internal layers of the bone phantom mimic the cortical bone and trabecular bone, respectively. Liquid tissue-mimicking mixtures (TMM) for normal bone, osteoporotic bone, and osteoarthritis bone were prepared. The phantoms were placed in the imaging prototype and the electromagnetic inverse scattering problem was solved using the DBIM to create the complex permittivity images. An L 2 -based regularization approach was adopted along with the iterative method with adaptive thresholding for compressed sensing (IMATCS) to overcome the ill-posedness and to solve the underdetermined set of linear equations at each DBIM iteration. The reconstruction of dielectric properties of bone phantoms have shown that L 2 -IMATCS approach provides a robust reconstruction of diverse bone phantoms with acceptable accuracy. Moreover, the osteoporotic and osteoarthritis bone phantoms were distinguished based on reconstructed dielectric properties with an average percentage difference of 26% at 3 GHz. This paper has made the first attempt to validate an MWI prototype for bone imaging application. A DBIM-based iterative method has been employed to classify normal and diseased bone phantoms.INDEX TERMS Bone health, calcaneus bone phantom, dielectric properties, distorted born iterative method, microwave imaging.BILAL AMIN received the B.S. degree (Hons.

show abstract

Microwave Bone Imaging: A Preliminary Investigation on Numerical Bone Phantoms for Bone Health Monitoring

Cited by 17 publications

References 47 publications

An Ex Vivo Study of Wireless Linkage Distance between Implantable LC Resonance Sensor and External Readout Coil

An Ex Vivo Study of Wireless Linkage Distance between Implantable LC Resonance Sensor and External Readout Coil

Dielectric Characterization of Healthy Human Teeth from 0.5 to 18 GHz with an Open-Ended Coaxial Probe

Experimental Validation of Microwave Imaging Prototype and DBIM-IMATCS Algorithm for Bone Health Monitoring

Contact Info

Product

Resources

About