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Objective: The Wavelia Microwave Breast Imaging (MBI) system, based on non-ionising imaging technology, has demonstrated exciting potential in the detection and localisation of breast pathology in symptomatic patients. In this study, the ability of the system to accurately estimate the size and likelihood of malignancy of breast lesions is detailed, and its clinical usefulness determined. Methods: Institutional review board and Health Products Regulatory Authority (HPRA) approval were obtained. Patients were recruited from the symptomatic unit to three groups; breast cancer (Group-1), unaspirated cysts (Group-2) and biopsied benign lesions (Group-3). MBI, radiological and histopathological findings were reviewed. MBI size estimations were compared with the sizes determined by conventional imaging and histopathology. A Quadratic Discriminant Analysis (QDA) classifier was trained in a 3D feature space to discriminate malignant from benign lesions. An independent review was performed by two independent breast radiologists. Results: 24 patients (11 Group-1, 8 Group-2 and 5 Group-3) underwent MBI. The Wavelia system was more accurate than conventional imaging in size estimation of breast cancers. The QDA accurately separated benign from malignant breast lesions in 88.5% of cases. The addition of MBI and the Wavelia malignancy risk calculation was deemed useful by the two radiologists in 70.6% of cases. Conclusion: The results from this MBI investigation demonstrate the potential of this novel system in estimating size and malignancy risk of breast lesions. This system holds significant promise as a potential non-invasive, comfortable, and harmless adjunct for breast cancer diagnosis. Further larger studies are under preparation to validate the findings of this study. Advances in knowledge: This study details the potential of the Wavelia MBI system in delineating size and malignancy risk of benign and malignant breast lesions in a symptomatic cohort. The usefulness of the Wavelia system is assessed in the clinical setting.

Rationale and Objectives Microwave Breast Imaging (MBI) is an emerging non-ionising technology with the potential to detect breast pathology. The investigational device considered in this article is a low-power electromagnetic wave MBI prototype that demonstrated the ability to detect dielectric contrast between tumour phantoms and synthetic fibroglandular tissue in preclinical studies. Herein, we evaluate the MBI system in the clinical setting. The capacity of the MBI system to detect and localise breast tumours in addition to benign breast pathology is assessed. Secondly, the safety profile and patient experience of this device is established. Materials and Methods Female patients were recruited from the symptomatic unit to 1 of 3 groups: Biopsy-proven breast cancers (Group-1), unaspirated cysts (Group-2) and biopsy-proven benign breast lesions (Group-3). Breast Density was determined by Volpara VDM (Volumetric Density Measurement) Software. MBI, radiological, pathological and histological findings were reviewed. Subjects were surveyed to assess patient experience. Results A total of 25 patients underwent MBI. 24 of these were included in final data analysis (11 Group-1, 8 Group-2 and 5 Group-3). The MBI system detected and localised 12 of 13 benign breast lesions, and 9 out of the 11 breast cancers. This included 1 case of a radiographically occult invasive lobular cancer. No device related adverse events were recorded. 92% (n = 23) of women reported that they would recommend MBI imaging to other women. Conclusion The MBI system detected and localized the majority of breast lesions. This modality may have the potential to offer a non-invasive, non-ionizing and painless adjunct to breast cancer diagnosis. Further larger studies are required to validate the findings of this study.

This paper presents a method for transforming the coordinates of regions of interest from 2D mammograms to a 3D spatial reference frame using estimates of breast tissue thickness provided by an available software for mammography data analysis. The method was developed to assist in interpreting and validating the 3D findings of a microwave breast imaging apparatus known as Wavelia against mammography. Results from the First-in-Human clinical investigation with the Wavelia system are used to illustrate the potential and feasibility of the proposed technique.

Many clinical investigations of microwave breast imaging systems are ongoing. However, few studies have investigated the optimal antenna design to maximise imaging performance. In this paper, the impact of the radial behaviour of the antenna on coverage area is investigated. A simplified antenna model in a homogeneous medium is used to estimate the power density and hence the coverage within the antenna array. Results from different antenna array configurations are compared, showing coverage can vary depending on the number of antennas used for multistatic imaging. The analysis is repeated for a lossy medium and highlights that losses increase the coverage estimation, although higher power and better signal-to-noise ratio would be required.In summary, this paper shows that the antenna radial behaviour can influence the coverage. In summary, this paper identifies preliminary limits on antenna design parameters to maximise coverage.

In this paper, preliminary results of the first-in-human clinical investigation with the Wavelia Microwave Breast Imaging (MBI) system prototype are presented. The clinical feasibility of the system, in terms of potential to detect both malignant and benign palpable breast lesions, is illustrated with the MBI results of two patient scans. Some identified technical challenges related to the patient positioning and breast deformation are also discussed.

This paper focuses on the data preprocessing scheme, as well as on the frequency selection and spatial filtering modules integrated with a Time-Reversal Multiple Signal Classification (TR-MUSIC) algorithm, for microwave breast imaging. This algorithm is part of the data processing chain of the Wavelia Microwave Breast Imaging (MBI) system prototype, which has been recently installed at the University Hospital of Galway, Ireland, for a first-in-human clinical trial. Indicative results from application of the algorithm on an experimental phantom dataset, and on a first patient dataset, are presented in this paper. Good correspondence between the two datasets is demonstrated, confirming the validity of the experimental setup used so far for the on-site acceptance of the Wavelia system, after installation at the hospital for clinical testing.

Background Total knee arthroplasty (TKA) reduces knee extensor muscle strength (KES) in the operated limb for several months after the surgery. Immediately after TKA, compared to either inguinal femoral nerve block or placebo, adductor canal block (ACB) better preserves KES. Whether this short-term increase in KES is maintained several weeks after surgery remains unknown. We hypothesized that 48 hours of continuous ACB immediately after TKA would improve KES 6 weeks after TKA, compared to placebo. Methods Patients scheduled for primary unilateral TKA were randomized to receive either a continuous ACB (group ACB) or a sham block (group SHAM) for 48 hours after surgery. Primary outcome was the difference in maximal KES 6 weeks postoperatively, measured with a dynamometer during maximum voluntary isometric contraction. Secondary outcomes included postoperative day 1 (POD1) and day 2 (POD2) KES, pain scores at rest and peak effort, and opioid consumption; variation at 6 weeks of Knee Osteoarthritis Outcome Score, patient satisfaction, and length of hospital stay. Results Sixty-three subjects were randomized and 58 completed the study. Patients in group ACB had less pain at rest during POD1 and during peak effort on POD1 and POD2, consumed less opioids on POD1 and POD2, and had higher median KES on POD1. There was no significant difference between groups for median KES on POD2, variation of Knee Osteoarthritis Outcome Score, patient satisfaction, and length of stay. There was no difference between groups in median KES 6 weeks after surgery (52 Nm [31-89 Nm] for group ACB vs 47 Nm [30-78 Nm] for group SHAM, P= .147). Conclusions Continuous ACB provides better analgesia and KES for 24-48 hours after surgery, but does not affect KES 6 weeks after TKA. Further research could evaluate whether standardized and optimized rehabilitation over the long term would allow early KES improvements with ACB to be maintained over a period of weeks or months.

International audience; Dans cet article, la Théorie Modale Elargie (MET) est développée pour les guides d'onde cylindriques à métamatériaux 2D. Un code basé sur la Méthode des Eléments Finis (FEM) calcule les impédances de surface équivalentes des métamatériaux dans la résolution de la MET. Ainsi, les diagrammes de dispersion sont obtenus avec des temps de simulation très réduits par rapport au logiciel commercial HFSS.

Wavelia is a low-power electromagnetic wave breast imaging device for breast cancer diagnosis, which consists of two subsystems, both performing non-invasive examinations: the Microwave Breast Imaging (MBI) subsystem and the Optical Breast Contour Detection (OBCD) subsystem. The Wavelia OBCD subsystem is a 3D scanning device using an infrared 3D stereoscopic camera, which performs an azimuthal scan to acquire 3D point clouds of the external surface of the breast. The OBCD subsystem aims at reconstructing fully the external envelope of the breast, with high precision, to provide the total volume of the breast and morphological data as a priori information to the MBI subsystem. This paper presents a new shape-based calibration procedure for turntable-based 3D scanning devices, a new 3D breast surface reconstruction method based on a linear stretching function, as well as the breast volume computation method that have been developed and integrated with the Wavelia OBCD subsystem, before its installation at the Clinical Research Facility of Galway (CRFG), in Ireland, for first-in-human clinical testing. Indicative results of the Wavelia OBCD subsystem both from scans of experimental breast phantoms and from patient scans are thoroughly presented and discussed in the paper.

International audience;  Abstract-In this article, the Modal Expansion Theory is applied to 2D metamaterial cylindrical waveguides. A new code to compute the surface impedances with 2D Finite Element Method is put forward. The surface impedances depend on the frequency and the incidence angle. The characterization of propagation in a 2D metamaterial waveguide is presented by using the Modal Expansion Theory and 2D Finite Element Method. Comparisons with the software HFSS are carried out in order to validate the new method.

This paper presents the Wavelia microwave breast imaging system that has been recently installed at the Galway University Hospital, Ireland, for a first-in-human pilot clinical test. Microwave breast imaging has been extensively investigated over the last two decades as an alternative imaging modality that could potentially bring complementary information to state-of-the-art modalities such as X-ray mammography. Following an overview of the main working principles of this technology, the Wavelia imaging system architecture is presented, as are the radar signal processing algorithms that are used in forming the microwave images in which small tumors could be detectable for disease diagnosis. The methodology and specific quality metrics that have been developed to properly evaluate and validate the performance of the imaging system using complex breast phantoms that are scanned at controlled measurement conditions are also presented in the paper. Indicative results from the application of this methodology to the on-site validation of the imaging system after its installation at the hospital for pilot clinical testing are thoroughly presented and discussed. Given that the imaging system is still at the prototype level of development, a rigorous quality assessment and system validation at nominal operating conditions is very important in order to ensure high-quality clinical data collection.

International audience; In this article the Modal Expansion Theory (MET) is developed for 2D metamaterial cylindrical waveguides. A new code based on 2D Finite Element Method (FEM) is implemented to compute conformal surface impedances. The MET using this FEM code is successfully applied to waveguides with different-invariant metamaterials. For such cases, computation time is at least 30 times faster than the commercial software HFSS.

Current techniques for testing of aircraft radomes are time consuming, not as precise as desired, and requires dedicated far field test range, compact test range, or anechoic chamber, or other specific systems for measuring one or other of the parameters. To overcome all these limitations, and to obtain a unique system for a complete diagnosis, a novel technique of radome characterization is proposed and detailed in this article. Based on a Near-Field network of probes placed in the vicinity of the radome under test, this innovative Near-Field measurement system is fully compliant with the updated standard RTCA/DO213A and leads to accurate evaluation of many parameters such as transmission efficiency and beamwidth, while reducing the measurement time required.

This paper presents a compact X-band antenna with an isoflux radiation pattern and circular polarization. It consists of a miniaturized helix antenna connected to a stripline circuit that provides a sequential rotation feeding. The antenna is arranged over a vertically corrugated ground plane and it has been optimized for a CubeSat 3U nano-satellite platform. Its design, manufacture and results are here presented.

La conférence prévue le 30 Mars 2020 a eu lieu sous un format virtuel du lundi 23 novembre au mercredi 25 novembre 2020.; International audience; Les dimensions des sondes sont des paramètres critiques lorsqu'elles sont utilisées en mesure champ proche des antennes. En effet, les propriétés radioélectriques de la sonde ne doivent pas impacter les mesures de l'antenne. Dans cet article, la Théorie Modale Élargie est utilisée pour concevoir un guide d'onde ouvert à section réduite à métamatériaux.

International audience; Dans cet article, une nouvelle méthode pour la reconstruction des propriétés de dispersion de guides rectangulaires à métamatériaux 2D est proposée. Un al-gorithme qui estime l'angle d'incidence correct du mode électromagnétique guidé à chaque fréquence est présenté. Cette approche est validée en comparant les résultats d'une structure anisotrope 2D avec ceux obtenus sous un logiciel commercial.