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Three critical problems, including high-cost instrumentations, time-consuming image recovery, and low image quality, limit clinical applications of diffuse optical tomography (DOT). Image reconstruction based on deep learning can enhance the image quality of DOT, especially in the case of low number of measurements where image reconstruction becomes a more ill-posed and underdetermined problem. Here, we present a sparse-view image reconstruction based on deep learning to recover the absorption coefficient of a phantom. The presented neural network enhances image quality and the results show that deep learning can enhance the contrast to noise-ratio effectively (more than 80%). The presented method provides recovered images with more accurate localization capabilities (an increase in localization metric by more than 30% compared with the classic method). Moreover, the time of image reconstruction is reduced by three orders of magnitude. This method can be applied for single-source DOT that significantly reduces the cost of required instruments for brain imaging and cervical or thyroid cancer screening. [ABSTRACT FROM AUTHOR]

This study designs a microstrip patch antenna with an inverted T-type notch in the partial ground to detect tumor cells inside the human breast. The size of the current antenna is small enough (18 mm × 21 mm × 1.6 mm) to distribute around the breast phantom. The operating frequency has been observed from 6–14 GHz with a minimum return loss of −61.18 dB and the maximum gain of current proposed antenna is 5.8 dBi which is flexible with respect to the size of antenna. After the distribution of eight antennas around the breast phantom, the return loss curves were observed in the presence and absence of tumor cells inside the breast phantom, and these observations show a sharp difference between the presence and absence of tumor cells. The simulated results show that this proposed antenna is suitable for early detection of cancerous cells inside the breast. Graphic Abstract [ABSTRACT FROM AUTHOR]

Background: Monoexponential apparent diffusion coefficient (ADC) and biexponential intravoxel incoherent motion (IVIM) analysis of diffusion‐weighted imaging is helpful in the characterization of breast tumors. However, repeatability/reproducibility studies across scanners and across sites are scarce. Purpose: To evaluate the repeatability and reproducibility of ADC and IVIM parameters (tissue diffusivity (Dt), perfusion fraction (Fp) and pseudo‐diffusion (Dp)) within and across sites employing MRI scanners from different vendors utilizing 16‐channel breast array coils in a breast diffusion phantom. Study Type: Phantom repeatability. Phantom: A breast phantom containing tubes of different polyvinylpyrrolidone (PVP) concentrations, water, fat, and sponge flow chambers, together with an MR‐compatible liquid crystal (LC) thermometer. Field Strength/Sequence: Bipolar gradient twice‐refocused spin echo sequence and monopolar gradient single spin echo sequence at 3 T. Assessment: Studies were performed twice in each of two scanners, located at different sites, on each of 2 days, resulting in four studies per scanner. ADCs of the PVP and water were normalized to the vendor‐provided calibrated values at the temperature indicated by the LC thermometer for repeatability/reproducibility comparisons. Statistical Tests: ADC and IVIM repeatability and reproducibility within and across sites were estimated via the within‐system coefficient of variation (wCV). Pearson correlation coefficient (r) was also computed between IVIM metrics and flow speed. A P value <0.05 was considered statistically significant. Results: ADC and Dt demonstrated excellent repeatability (<2%; <3%, respectively) and reproducibility (both <5%) at the two sites. Fp and Dp exhibited good repeatability (mean of two sites 3.67% and 5.59%, respectively) and moderate reproducibility (mean of two sites 15.96% and 13.3%, respectively). The mean intersite reproducibility (%) of Fp/Dp/Dt was 50.96/13.68/5.59, respectively. Fp and Dt demonstrated high correlations with flow speed while Dp showed lower correlations. Fp correlations with flow speed were significant at both sites. Data Conclusion: IVIM reproducibility results were promising and similar to ADC, particularly for Dt. The results were reproducible within both sites, and a progressive trend toward reproducibility across sites except for Fp. Level of Evidence: 2 Technical Efficacy: Stage 1 [ABSTRACT FROM AUTHOR]

This paper presents cancer tumor detection in the breast phantom and cancer tissue detection in the excised breast tissue phantom by the ultra-wideband terahertz microstrip patch antenna. The proposed antenna structure consists of a silicon dioxide substrate with a dielectric constant of 3.9 and a thickness of 200 µm, a radiating gold patch of length 560 µm, width 700 µm, and thickness 36 µm which is on top of the substrate, and an array of 6 × 6 gold Split Ring Resonator at the ground plane. Each SRR is separated by 28.75 µm. An array of SRR at the antenna's ground plane enhances bandwidth, efficiency, gain, directivity and reduces back radiation. The antenna operates in the frequency range of 0.1-3 THz, with a gain of 19.22 dBi and an efficiency of 98.74%. The antenna setup with the breast phantom and excised breast tissue phantom in between have been designed and analyzed in the CST microwave studio 2019 version. Tumor in the breast phantom and the cancerous tissue in the breast tissue phantom can be detected by placing the phantoms between the two identical antennas. The difference in the dielectrics of the breast and the tumor layers can determine the difference between healthy and malignant tissue. A typical breast phantom model that replicates a real-human breast and a specific excised tissue that replicates the actual breast tissue with and without cancer tissue in terms of dielectric and optical properties has been employed in this study to detect the tumor and cancerous tissue. [ABSTRACT FROM AUTHOR]

Breast cancer is the most prevalent cancer in females in a large number of countries around the world. One in every twenty females gets confirmed to have breast cancer during their lifetime, though the number varies significantly by country. There are various conventional methods to spot the breast cancer cells, such as magnetic resonance imaging, X-ray mammography, biopsies, and ultrasound. The early identification of cancer cells helps to save many human lives. This paper investigates tumor detection in a breast phantom using a Photonic crystal (PhC) based hourglass terahertz patch antenna. This paper designed four different antenna structures: conventional hourglass patch antenna (with and without breast phantom) and PhC-based hourglass patch antenna (with and without breast phantom). The proposed PhC antenna models and the breast phantom are designed using the CST studio suite and analyzed the various antenna parameters. The observed S11 parameter for the proposed structures is − 21.50, − 25.34, − 33.78 and − 50.32 dB. The proposed antenna resonated in THz frequency, which does not affect human health and is safer due to non-ionizing characteristics. The suggested PhC structure is tiny, less expensive, lightweight, environmentally benign, and can be utilized as a primary screening technique for people with breast cancer, especially in resource-limited areas. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to develop an in-house breast phantom, and assess students’ knowledge and satisfaction after using it for mammographic positioning training. Material and Methods: The breast phantom was designed in a half-body shape, and constructed primarily using gelcoat resin, polyurethane foam, and thermoreversible gel. Additionally, silicone type RA-210, known for its high flexibility, tensile strength, elongation at break (620%), and ability to revert to its original shape, was incorporated. This study evaluated the effectiveness of the breast phantom utility in improving students’ knowledge through a nine-item questionnaire; employing a one-group pre-post design. The participants, consisting of 63 Radiologic Technology students, whom rated their satisfaction with the phantom for training purposes using a five-point Likert scale. Results: The mean knowledge score for the breast phantom positioning significantly improved from 5.35±1.61 points (pretest) to 7.32±1.20 points (post-test), following training (p-value

Ultra Wideband radar systems have emerged as a good alternative for non-invasive and harmless breast cancer detection. In this paper, bistatic and monostatic radar systems are proposed, which detects the deep-rooted and smallest formation of the tumor in the breast. The source signal for transmission through the breast is a seventh derivative Gaussian Ultra Wideband pulse. This pulse is shaped using the proposed sharp transition bandpass Finite Impulse Response filter. The pulse shaper filter design has a sharp transition, hence efficient for shaping very short-duration pulses, achieving higher data rate and less interference issues. Also, the pulse tightly fits the Federal Communication Commission spectral mask, thus achieving higher spectral utilization efficiency and meeting the signal safety standards for transmission through the breast. The shaped pulse fed to the antenna of the radar system provides higher antenna radiation efficiency and radiating power due to the concentration of power in the main lobe, sidelobe suppression, and less channel loss. Tumor detection is based on the time and frequency domain analysis of the backscattered signals from the tumor. These signals have higher amplitude, higher electric field intensity variations, and an increase in the scattering parameter values due to the presence of tumor. Simulation results show significant changes in the electric field intensity for normal and malignant breast tissue for tumor sizes ranging from 4 mm to 0.5 mm. To accurately detect the location of tumor inside the breast, Specific Absorption Rate (SAR) analysis is carried out. It is observed that the energy absorption in the cancerous breast is higher than that of the normal breast, thereby aids to detect the location of the tumor accurately by identifying the coordinates of the maximum value of SAR. The results obtained with an experimental setup consisting of fabricated heterogeneous breast phantom with tumor and monostatic radar closely confirms with the simulation results.

Background: To date, the accuracy and variability of diffusion‐weighted MRI (DW‐MRI) metrics have been reported in a limited number of scanner/protocol/coil combinations. Purpose: To evaluate the reproducibility of DW‐MRI estimates across multiple scanners and DW‐MRI protocols and to assess the effects of using an 8‐channel vs. 16‐channel breast coil in a breast phantom. Study Type: Prospective. Phantom: Breast phantom containing tubes of water and differing polyvinylpyrrolidone (PVP) concentrations with apparent diffusion coefficients (ADCs) matching breast tissue. Field Strength/Sequence: 3 T (three standard and one wide bore), three DW‐MRI single‐shot echo planar imaging protocols of varying acquired spatial resolution. Assessment: Accuracy of estimated ADCs was assessed using percent differences (PD) relative to nuclear magnetic resonance spectroscopy‐derived reference values. Coefficients of variation (CV) were calculated to determine variation across scanners. CVs based on the median standard deviation (CVM) were used to evaluate tube‐specific dispersion using 8‐ or 16‐channel coils at a single scanner. ADCs of PVP‐containing tubes were additionally normalized by the median water tube ADC to account for temperature effects. Statistical Tests: Two‐way repeated measures analysis of variance and post hoc tests were used to evaluate differences in ADC, CV, and CVM across scanners and protocols (α = 0.05). Results: ADCs were within 11% (interquartile range [IQR] 7%) of reference values and significantly improved to 2% (IQR 7%) after normalization to an internal water reference. Normalization significantly reduced interscanner variability of ADC estimates from 7% to 4%. DW‐MRI protocol did not affect ADC accuracy; however, the clinical and higher‐resolution clinical protocols resulted in the greatest (9%) and least (6%) interscanner variability, respectively. The 8‐ and 16‐channel receive coils yielded similar accuracy (PD: 12% vs. 16%) and precision (CVM: 2.7% vs. 2.9%). Data Conclusion: Normalization by an internal reference improved interscanner ADC reproducibility. High‐resolution protocols yielded comparably accurate and significantly less variable ADCs compared to a clinical standard protocol. Evidence Level: 2 Technical Efficacy: Stage 1 [ABSTRACT FROM AUTHOR]

Purpose: To introduce a novel methodology for developing anthropomorphic breast phantoms for use in X-ray-based imaging modalities. Methods: "Hyperization" is a quasi-stippling mapping operation in which regions of varying grayscale values in a 2D image are transformed into regions of varying holes on a surface. The holes can be cut or engraved on the sheet of paper using a high-resolution laser cutter/engraver. In hyperization, the main parameters are the size and the distance between the holes. Here, we introduce the concept and chronicle the development and characterization of a proof-of-concept prototype. In this study, we hypothesized that a resulting "Hyperia" phantom would be a realistic representative of a patient's breast tissue: it would exhibit similar X-ray properties and show textural complexities. We used breast computed tomography (bCT) images of real patients as the input models. Using a previously developed segmentation method, the input CT images were segmented into different tissue classes (skin, adipose, and fibroglandular). The segmented images were then "Hyperized".A series of Monte Carlo simulations were conducted to find the optimal hyperization parameters. Different laser cutter/engraver systems and substrate materials were explored to find a viable option for developing an entire Hyperia breast phantom. The resulting phantom was imaged on a prototype breast CT system, and the resulting images were evaluated based on physical properties and similarity to the original patient data. Results: The simulation results indicate close similarities - both in the distribution of different tissue types and the resulting CT numbers - between the patient bCT image and the bCT of the Hyperia phantom, regardless of the breast size and density: the Pearson correlation coefficient (1) ranged from 0.88 in a BIRADS A breast to 0.94 in BIRADS C and D breasts (1 of 1.00 suggests perfect structural similarity), and the volumetric mean squared error ranged from 0.0033 (in BIRADS D breast) to 0.0059 (in BIRADS A), suggesting good agreement between the resulting CT numbers. For fabricating the slices, the office paper was found to be an optimal substrate material, with the Hyperization parameters of (a, ß) = (0.200 mm, 0.400 mm). Conclusion:A novel phantom can be used for X-ray-based breast cancer imaging systems. The main advantage is that only one material is used for creating a contrast between different tissue types in an image. [ABSTRACT FROM AUTHOR]

BackgroundBreast imaging technology plays an important role in breast cancer planning and treatment. Recently, three-dimensional (3D) printing technology has become a trending issue in phantom constructions for medical applications, with its advantages of being customizable and cost-efficient. However, there is no current practice in the field of multi-purpose breast phantom for quality control (QC) in multi-modalities imaging. The purpose of this study was to fabricate a multi-purpose breast phantom with tissue-equivalent materials via a 3D printing technique for QC in multi-modalities imaging.MethodsWe used polyvinyl chloride (PVC) based materials and a 3D printing technique to construct a breast phantom. The phantom incorporates structures imaged in the female breast such as microcalcifications, fiber lesions, and tumors with different sizes. Moreover, the phantom was used to assess the sensitivity of lesion detection, depth resolution, and detectability thresholds with different imaging modalities. Phantom tissue equivalent properties were determined using computed tomography (CT) attenuation [Hounsfield unit (HU)] and magnetic resonance imaging (MRI) relaxation times.ResultsThe 3D-printed breast phantom had an average background value of 36.2 HU, which is close to that of glandular breast tissue (40 HU). T1 and T2 relaxation times had an average relaxation time of 206.81±17.50 and 20.22±5.74 ms, respectively. Mammographic imaging had improved detection of microcalcification compared with ultrasound and MRI with multiple sequences [T1WI, T2WI and short inversion time inversion recovery (STIR)]. Soft-tissue lesion detection and cylindrical tumor contrast were superior with mammography and MRI compared to ultrasound. Hemispherical tumor detection was similar regardless of the imaging modality used.ConclusionsWe developed a multi-purpose breast phantom using a 3D printing technique and determined its value for multi-modal breast imaging studies.

Abstract Introduction The aim of this preliminary work was to determine if image quality in digital breast tomosynthesis (DBT) changes when tomosynthesis image slices were obtained at differing heights above the detector and in differing breast thicknesses. Methods A CIRS Model 020 BR3D breast imaging phantom was used to obtain the DBT images. The images were also acquired at different tube voltages, and each exposure was determined by the automatic exposure control system. Contrast‐to‐noise ratio (CNR) and figure‐of‐merit (FOM) values were obtained and compared. Results At a phantom thickness of 5 cm or greater, there was a significant reduction (P ≤ 0.05) of image CNR values obtained from the images near the top of the phantom to those obtained near the bottom of the phantom. When the phantom thickness was 4 cm, there was no significant difference in CNR values between DBT images acquired at any height in the phantom. FOM values generally showed no difference when images were obtained at differing heights above the detector. Conclusion Image quality, as measured by the CNR, was reduced when tomosynthesis slice image heights were at the top of the phantom and when the thickness of the phantom was more than 4 cm. From this preliminary work, clinicians need to be aware that DBT images obtained near the top of the breast, when breast thickness is greater than 4 cm, may have reduced image quality. Further work is needed to fully assess any DBT image quality changes when images are obtained near the top of the breast.

This article presents a flexible ultra-wideband 4 × 1 MIMO antenna for breast cancer detection application. The antenna is designed with CPW feeding. The proposed MIMO antenna is constructed with an elliptical-shaped radiating patch and a slotted ground plane. The main aim of using a 4 × 1 MIMO antenna is to improve antenna performance and scatting signals. Initially, a single CPW-fed antenna element is designed with dimension 16 × 16 × 0.254 mm3 and the design is extended to 4 × 1 MIMO antenna with dimension 16 × 71.5 × 0.254 mm3 by using the flexible material Rogers RT/duroid 5880 (tm). The 4 × 1 MIMO antenna operates from 3.2 GHz to 14 GHz frequency band with a directional radiation pattern. The performance of the antenna is observed in terms of S-parameters, gain, isolation, envelope correlation coefficient (ECC), diversity gains (DG), and specific absorption rate (SAR). S-parameters of transmitting and receiving antennas are observed with the help of breast phantom. All parameters are found within an acceptable range. [ABSTRACT FROM AUTHOR]

This work presents a flat‐gain antipodal Vivaldi antenna (AVA) for ultra‐wideband (UWB) microwave imaging applications. The proposed antenna demonstrates measured and simulated impedance bandwidth from 2.3 GHz to 20 GHz with a flat gain over the band, with minimum gain variation of 2.9 dBi. The antenna is tested initially for its practical utility by measuring its specific absorption rate (SAR) value. The SAR value is observed in the simulator by modeling a realistic homogeneous as well as a heterogeneous breast phantom. The SAR value obtained complies with both American and European standards when averaged over 1 g as well as 10 g of tissue. The designed antenna is further utilized to detect multiple tumors in a realistic homogeneous and heterogeneous breast phantoms developed in the laboratory environment. The widely popular delay and sum (DAS) algorithm is utilized to reconstruct the tumor images. The imaging is done outside the anechoic chamber with an in‐house monostatic microwave imaging setup just to make it more convincing with real‐world dynamic scenario. The homogeneous phantom with four embedded tumors each of radius 4 mm and the heterogeneous phantom with two tumors, one of radius 3.5 mm and another of radius 5 mm are imaged in this work. The imaging results demonstrate that tumors of different sizes can be detected accurately in the case of both homogeneous and heterogeneous breast phantoms. AVA with an oil paper layer for bandwidth enhancement as well for achieving flat‐gain response is first of its kind to be reported in this work Also, the proposed work utilizes different phantoms for imaging several tumors of differing sizes, which has not before been described. [ABSTRACT FROM AUTHOR]

Objectives: Iterative (eg, simultaneous algebraic reconstruction technique [SART]) and analytical (eg, filtered back projection [FBP]) image reconstruction techniques have been suggested to provide adequate three-dimensional (3D) images of the breast for capturing microcalcifications in digital breast tomosynthesis (DBT). To decide on the reconstruction method in clinical DBT, it must first be tested in a simulation resembling the real clinical environment. The purpose of this study is to introduce a 3D realistic breast phantom for determining the reconstruction method in clinical applications. Methods: We designed a 3D realistic breast phantom with varying dimensions (643-5123) mimicking some structures of a real breast such as milk ducts, lobules, and ribs using TomoPhantom software. We generated microcalcifications, which mimic cancerous cells, with a separate MATLAB code and embedded them into the phantom for testing and benchmark studies in DBT. To validate the characterization of the phantom, we tested the distinguishability of microcalcifications by performing 3D image reconstruction methods (SART and FBP) using Laboratory of Computer Vision (LAVI) open-source reconstruction toolbox. Results: The creation times of the proposed realistic breast phantom were seconds of 2.5916, 8.4626, 57.6858, and 472.1734 for 643, 1283, 2563, and 5123, respectively. We presented reconstructed images and quantitative results of the phantom for SART (1-2-4-8 iterations) and FBP, with 11 to 23 projections. We determined qualitatively and quantitatively that SART (2-4 iter.) yields better results than FBP. For example, for 23 projections, the contrast-to-noise ratio (CNR) values of SART (2 iter.) and FBP were 2.871 and 0.497, respectively. Conclusions: We created a computationally efficient realistic breast phantom that is eligible for reconstruction and includes anatomical structures and microcalcifications, successfully. By proposing this breast phantom, we provided the opportunity to test which reconstruction methods can be used in clinical applications vary according to various parameters such as the No. of iterations and projections in DBT. [ABSTRACT FROM AUTHOR]

This work introduces a microwave-based system able to detect tumours in breast phantoms in a non-invasive way. The data acquisition system is composed of a hardware system which involves high-frequency components (antennas, switches and cables), a microcontroller, a vector network analyser used as measurement instrument and a computer devoted to the control and automation of the operation of the system. Concerning the software system, the computer runs a Python script which is in charge of mastering and automatising all the required stages for the data acquisition, from initialisation of the hardware system to performing and saving the measurements. We also report on the design of the high-performance broadband antenna used to carry out the measurements, as well as on the algorithm employed to build the final medical images, based on an adapted version of the so-called Improved Delay-and-Sum (IDAS) algorithm improved by a Hamming window filter and averaging preprocessing. The calibration and start-up of the system are also described. The experimental validation includes the use of different tumour models with different dielectric properties inside the breast phantom. The results show promising tumour detection capabilities, even when there is low dielectric contrast between the tumoural and healthy tissues, as is the usual case for dense breasts in young women. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common cancer among women worldwide, with over 2 million new cases diagnosed each year. Early detection can be achieved by screening examinations such as mammography and ultrasonography. The latter has demonstrated advantages such as safety and sensitivity to dense breasts, but is often performed as a follow-up test after abnormal findings at mammography or on palpation. Indeed, the technique shows limitations of operator-dependence and non-reproducibility, since the quality of imaging is highly dependent on the skill of the technologist performing the examination. We therefore designed a diagnosis-assisting device comprising piezoresistive sensors of microscale thickness that can be attached to the ultrasound transducer. The operator is informed when excessive pressure is detected, allowing correction of the transducer position. Finally, we fabricated a breast phantom including tumors from agar and collagen to assess the effectiveness of the device. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this preliminary work was to determine if image quality in digital breast tomosynthesis (DBT) changes when tomosynthesis image slices were obtained at differing heights above the detector and in differing breast thicknesses. Methods: A CIRS Model 020 BR3D breast imaging phantom was used to obtain the DBT images. The images were also acquired at different tube voltages, and each exposure was determined by the automatic exposure control system. Contrast‐to‐noise ratio (CNR) and figure‐of‐merit (FOM) values were obtained and compared. Results: At a phantom thickness of 5 cm or greater, there was a significant reduction (P ≤ 0.05) of image CNR values obtained from the images near the top of the phantom to those obtained near the bottom of the phantom. When the phantom thickness was 4 cm, there was no significant difference in CNR values between DBT images acquired at any height in the phantom. FOM values generally showed no difference when images were obtained at differing heights above the detector. Conclusion: Image quality, as measured by the CNR, was reduced when tomosynthesis slice image heights were at the top of the phantom and when the thickness of the phantom was more than 4 cm. From this preliminary work, clinicians need to be aware that DBT images obtained near the top of the breast, when breast thickness is greater than 4 cm, may have reduced image quality. Further work is needed to fully assess any DBT image quality changes when images are obtained near the top of the breast. [ABSTRACT FROM AUTHOR]

The objective of this work is the design and validation of a directional Vivaldi antenna to detect tumor cells' electromagnetic waves with a frequency of around 5 GHz. The proposed antenna is 33% smaller than a traditional Vivaldi antenna due to the use of metamaterials in its design. It has an excellent return loss of 25 dB at 5 GHz and adequate radiation characteristics as its gain is 6.2 dB at 5 GHz. The unit cell size of the proposed metamaterial is 0.058λ × 0.054λ at the operation frequency of 5 GHz. The proposed antenna was designed and optimized in CST microwave software, and the measured and simulated results were in good agreement. The experimental study demonstrates that an array composed with the presented antennas can detect the existence of tumors in a liquid breast phantom with positional accuracy through the analysis of the minimum amplitude of Sii. [ABSTRACT FROM AUTHOR]

This experimental study investigated the significant different in image quality and dose between different automatic exposure of exposure parameter (AOP) mode in full field digital mammography (FFDM) system. CIRS012A and PMMA breast phantom (4cm, 5cm and 6 cm thickness) were used as subject using Senographe Essential FFDM system. TLD chip was used as dose measurement tool. Exposures were taken in cranio-caudal projection. 2 radiographers with more than 10 years of working experience in performing mammography scored the image independently. Kappa finds a good agreement between raters (kappa value=0.9, p0.05). DOSE mode is the preferred selection in optimizing between dose and image quality.

Abstract Background Breast cancer is the most commonly diagnosed malignancy in females and frequently requires core needle biopsy (CNB) to guide management. Adequate training resources for CNB suffer tremendous limitations in reusability, accurate simulation of breast tissue, and cost. The relatively recent advent of 3D printing offers an alternative for the development of breast phantoms for training purposes. However, the feasibility of this technology for the purpose of ultrasound (US) guided breast intervention has not been thoroughly studied. Methods We designed three breast phantom models that were printed in multiple resins available through Stratasys, including VeroClear, TangoPlus and Tissue Matrix. We also constructed several traditional breast phantoms using chicken breast and Knox gelatin for comparison. These phantoms were compared side-by-side for ultrasound penetrance, simulation of breast tissue integrity, anatomic accuracy, reusability, and cost. Results 3D printed breast phantoms were more anatomically accurate models than traditional breast phantoms. The chicken breast phantom provided acceptable US beam penetration and material hardness for simulation of human breast tissue integrity. Sonographic image quality of the chicken breast phantom was the most accurate overall. The gelatin-based phantom also had acceptable US beam penetration and image quality; however, this material was too soft and poorly simulated breast tissue integrity. 3D printed phantoms were not visible under US. Conclusions There is a large unmet need for a printable material that is truly compatible with multimodality imaging for breast and other soft tissue intervention. Further research is warranted to create a realistic, reusable and affordable material to 3D print phantoms for US-guided intervention training.

In this study, a method of directly evaluating the dose received by the highly radiation-sensitive mammary gland during mammography was investigated, and a corresponding breast phantom was produced that expresses a mammary gland, as an alternative to the existing mixed-form phantom. After designing this breast phantom by performing Monte Carlo simulations, the glandular dose was evaluated and compared with that of a mixed-form phantom. Then, dose evaluation was conducted for current commercial filament materials that could be used to fabricate the phantom by 3-D printing. The results showed that the dose received by the mammary gland was in the range of 1.089-1.237 mGy, and the average difference from that determined using the mixed-form phantom was approximately 1.2 %. Among the filament materials, polylactic acid showed the dose that was the most similar to that of the mammary gland tissue, differing by approximately 2.4 %. Overall, the research results suggest that it is meaningful to evaluate the glandular dose using the developed phantom instead of a mixed-form phantom. Besides, polylactic acid is the most appropriate material for fabricating the mammary gland tissue using a 3-D printer.

Objective(s): Breast cancer is a fatal disease and the leading cause of mortality in women. Radiofrequency hyperthermia is an approach to the treatment of cancer cells through increasing their temperature. The present study aimed to investigate breast tumor ablation via radiofrequency hyperthermia in the presence and non-presence states of magnetite nanoparticles and assess the effects of magnetite nanoparticles on breast cancer treatment in hyperthermia.Materials and Methods: Radius hemisphere geometry (5 cm) was designed, which was similar to an actual breast based on the fat tissues, glandular tissues as a semi-oval embedded in the hemisphere, and a radius sphere (1 cm) as a tumor region inside. After utilization in a three-dimensional printer, each layer of the phantom was filled with a proper combination of oil-gelatin with similar dielectric and thermal properties to an actual breast. To evaluate the effects of the magnetite nanoparticles, three weights of the magnetite were added to the tumor region (0.01, 0.05, and 0.1 g). Finally, the phantom was placed in a radiofrequency device with the frequency of 13.56 MHz.Results: Temperature differences were measured at four different points of the phantom. The power and time in the treatment were estimated at 40 watts and five minutes, respectively. The temperature and specific absorption rate plots were obtained for all the states in several graphs for five minutes.The results showed that the heat generation with the utilization of the magnetite state was higher by approximately 2.5-7˚C compared to the state without magnetite. Furthermore, the temperature of 0.05 gram of magnetite indicated that without causing damage in the healthy tissues, the entire tumor region could attain adequate heat uniformly (6.1-6.4˚C). Conclusion: Therefore, it could be concluded that 0.05 gram of magnetite could cause ablation in the entire tumor region.

In this study, breast phantoms were fabricated by emulating glandular and adipose tissues separately using a three‐dimensional (3D) printer. In addition, direct and quantitative glandular dose evaluations were performed. A quantitative method was developed to evaluate the glandular and adipose tissues separately when performing glandular dose evaluations. The variables used for glandular dose evaluation were breast thickness, glandular tissue ratio, and additional filter materials. The values obtained using a Monte Carlo simulation and those measured using a glass dosimeter were compared and analyzed. The analysis showed that as the glandular tissue ratio increased, the dose decreased by approximately 10%, which is not a significant variation. The comparison revealed that the simulated values of the glandular dose were approximately 15% higher than the measured values. The use of silver and rhodium filters resulted in a mean simulated dose of 1.00 mGy and 0.72 mGy, respectively, while the corresponding mean measured values were 0.89 mGy ± 0.03 mGy and 0.62 mGy ± 0.02 mGy. The mean glandular dose can be reliably evaluated by comparing the simulated and measured values. [ABSTRACT FROM AUTHOR]

This work introduces a microwave-based system able to detect tumours in breast phantoms in a non-invasive way. The data acquisition system is composed of a hardware system which involves high-frequency components (antennas, switches and cables), a microcontroller, a vector network analyser used as measurement instrument and a computer devoted to the control and automation of the operation of the system. Concerning the software system, the computer runs a Python script which is in charge of mastering and automatising all the required stages for the data acquisition, from initialisation of the hardware system to performing and saving the measurements. We also report on the design of the high-performance broadband antenna used to carry out the measurements, as well as on the algorithm employed to build the final medical images, based on an adapted version of the so-called Improved Delay-and-Sum (IDAS) algorithm improved by a Hamming window filter and averaging preprocessing. The calibration and start-up of the system are also described. The experimental validation includes the use of different tumour models with different dielectric properties inside the breast phantom. The results show promising tumour detection capabilities, even when there is low dielectric contrast between the tumoural and healthy tissues, as is the usual case for dense breasts in young women.

Breast cancer is a public health problem and has the highest incidence and mortality in the female population worldwide. Early detection of breast cancer is essential for reducing the morbidity and mortality associated with this disease. Some methods for detecting breast tumors include ultrasonography, magnetic resonance imaging, positron emission tomography, tomosynthesis, and mammography, which are recommended as screening techniques. Each method has its advantages and disadvantages, such as discomfort to the patient during examination, possible reactions to the contrast agent, radiation emission, operator dependence for the analysis of results, difficulty of detection in dense tissues, lack of access for people with disabilities or low mobility, high cost, and radioactive waste production. The main objective of this work is to apply the electromechanical impedance method to the detection of inclusions so that it can be used as an alternative to existing techniques for the detection of breast tumors. The application of the electromechanical impedance method using piezoelectric transducers, acting simultaneously as sensors and actuators, coupled to the analyzed structure allows the monitoring of mass, rigidity, and/or damping variations, and consequent detection of inclusions. The detection of inclusions is possible owing to damage metrics, which are statistical parameters capable of numerically representing the difference between two measurements before and after damage. In this work, silicone samples and phantom breast models were analyzed. In addition, it was observed that external heating imposed on the models and the presence of heat generation in the inclusions aided detection. This work presents important contributions in the analysis of structural behavior, expanding the applications of damage detection techniques to hyperplastic materials. [ABSTRACT FROM AUTHOR]

In this paper, a system for microwave breast tumor detection is presented using iteratively corrected coherence factor delay and sum (CF-DAS) algorithm. CF-DAS is data independent, which makes it stable in a noisy environment. However, data adaptive techniques have made significant progress by enhancing the image quality in microwave tomography. Thus, a novel data adaptive iterative variant of CF-DAS is proposed in this paper to produce stable and accurate images. The microwave imaging (MI) system contains a rotatable array of nine modified antipodal Vivaldi antennas in a circular arrangement, an array-mounting stand based on the stepper motor, the flexible phantom mounting podium, a control system for RF switching of the transceivers, and signal processing unit based on personal computer involved in the reconstruction of the image. The impedance bandwidth of the modified antenna is recorded from 2.5 to 11 GHz with stable directional radiation pattern. For performing the transmission and reception of the microwave signals, an SP8T nine port RF switch is used ranging from 2.5 to 8.0 GHz, and the switching is controlled by MATLAB software. Several low-cost lab-based homogenous and heterogeneous phantoms containing the dielectric property of human breast and tumor tissue are prepared to test the system efficiency. Since typical data independent radar-based techniques are ill-equipped for multiple reflection scenarios, an iteratively corrected variant of CF-DAS algorithm is used for processing the recorded backscattered signals to reconstruct the image of the breast phantom and to identify the existence and locate the area of the multiple breast tumors. The proposed method achieves more than 10-dB improvement over conventional CF-DAS in terms of signal to mean ratio for four different phantoms measured in this study.

The objective of this work is the design and validation of a directional Vivaldi antenna to detect tumor cells’ electromagnetic waves with a frequency of around 5 GHz. The proposed antenna is 33% smaller than a traditional Vivaldi antenna due to the use of metamaterials in its design. It has an excellent return loss of 25 dB at 5 GHz and adequate radiation characteristics as its gain is 6.2 dB at 5 GHz. The unit cell size of the proposed metamaterial is 0.058λ × 0.054λ at the operation frequency of 5 GHz. The proposed antenna was designed and optimized in CST microwave software, and the measured and simulated results were in good agreement. The experimental study demonstrates that an array composed with the presented antennas can detect the existence of tumors in a liquid breast phantom with positional accuracy through the analysis of the minimum amplitude of Sii.

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Purpose: Oncoplastic breast surgery (OBS) is gaining popularity among surgeons for breast-conserving surgery treatments. OBS relies on complex relocation and deformation of breast tissue involving the tumor bed (TB). In this study, we investigate the validity of using surgical clips with OBS for accurate TB delineation in adjuvant, targeted breast radiotherapy. Methods: Different OBS techniques were simulated on realistic breast phantoms. Surgical clips were used to demarcate the TB. Following tumor resection and closure, the true TB (TBTrue) was extracted. Each phantom was CT imaged at several phases of surgery in order to record pre- and post-OBS closure surgical clip displacements. Two senior radiation oncologists (ROs) were asked to delineate TBs on CTs by relying on surgical clips placed as per standard protocol, and by referring to operative notes. Their original contours, as well as those expanded using 5–15 mm margins, were compared with the accurate TBTrue using the dice similarity coefficient (DSC), Hausdorff Distance (HD), and over- and under-contoured volumes. Inter- and intra-RO contour agreements were also evaluated. Results: Post-OBS surgical clips were significantly displaced outside the original breast quadrant. Inter- and Intra-RO TB contours were consistent, yet systematically differed from TBTrue (DSC values range = 0.38 to 0.69, and maximum HD range = 17.8 mm to 38.0 mm). Using expansion margins did not improve contour congruence and caused significant over-contoured volumes. Conclusion: Following OBS, surgical clips alone are not reliable radiographic surrogates of TB locations and accurate TB delineation is challenging. For complex OBS cases, indication of any type of partial breast irradiation is very questionable. [ABSTRACT FROM AUTHOR]

This research article presents a proficient, convenient, and low‐cost monostatic radar‐based microwave imaging (RBMI) technique for the breast tumor detection. For this, a compact cubical dielectric resonator antenna (DRA) with impedance bandwidth of 8.3 GHz (ie, 4.3‐12.6 GHz) has been simulated using CST V′17. In proposed monostatic RBMI technique, the designed DRA is placed parallel to the breast phantom and rotated around it at an interval of 10° in elevation plane (0‐π) and azimuthal plane (0‐2π), respectively; first, without and then with tumor inside the breast phantom. Total 1080 back‐scattered signals are recorded for the entire impedance bandwidth, and processed for microwave imaging. For the validation of results, fabricated antenna is rotated around the artificial breast mimic. The artificial breast mimic is made up from gelatin (skin), petroleum jelly (fat), and wheat flour (tumor). The backscattered signals from the artificial breast phantom have been recorded on the vector network analyzer model no. E5063A for both the cases that is, with absence and presence of tumor at different position and time intervals. The recorded S‐parameters have been processed in two beam‐forming algorithms; delay and sum (DAS), delay multiply and sum (DMAS). These signals are then converted into digital data and processed in the MATLAB, to visualize the 2D image of the scanned area to detect the breast tumor. By comparing the reconstructed images, it is concluded that the DAS algorithm provides just a clue about the presence of the tumor, but DMAS provides the accurate position and size of the breast tumor. [ABSTRACT FROM AUTHOR]

Background: In breast diffusion-weighted imaging (DWI), distortion and physiologic artifacts affect clinical interpretation. Image quality can be optimized by addressing the effect of phase encoding (PE) direction on these artifacts., Purpose: To compare distortion artifacts in breast DWI acquired with different PE directions and polarities, and to discuss their clinical implications., Study Type: Prospective., Population: Eleven healthy volunteers (median age: 47 years old; range: 22-74 years old) and a breast phantom., Field Strength/sequence: Single-shot echo planar DWI and three-dimensional fast gradient echo sequences at 3 T., Assessment: All DWI data were acquired with left-right, right-left, posterior-anterior, and anterior-posterior PE directions. In phantom data, displacement magnitude was evaluated by comparing the location of landmarks in anatomical and DWI images. Three breast radiologists (5, 17, and 23 years of experience) assessed the presence or absence of physiologic artifacts in volunteers' DWI datasets and indicated their PE-direction preference., Statistical Tests: Analysis of variance with post-hoc tests were used to assess differences in displacement magnitude across DWI datasets and observers. A binomial test and a chi-squared test were used to evaluate if each in vivo DWI dataset had an equal probability (25%) of being preferred by radiologists. Inter-reader agreement was evaluated using Gwet's AC1 agreement coefficient. A P-value <0.05 was considered statistically significant., Results: In the phantom study, median displacement was the significantly largest in posterior-anterior data. While the displacement in the anterior-posterior and left-right data were equivalent (P = 0.545). In the in vivo data, there were no physiological artifacts observed in any dataset, regardless of PE direction. In the reader study, there was a significant preference for the posterior-anterior datasets which were selected 94% of the time. There was good agreement between readers (0.936)., Data Conclusion: This study showed the impact of PE direction on distortion artifacts in breast DWI. In healthy volunteers, the posterior-to-anterior PE direction was preferred by readers., Level of Evidence: 2 TECHNICAL EFFICACY: Stage 1., (© 2024 International Society for Magnetic Resonance in Medicine.)

In this study, a method of directly evaluating the dose received by the highly radiation-sensitive mammary gland during mammography was investigated, and a corresponding breast phantom was produced that expresses a mammary gland, as an alternative to the existing mixed-form phantom. After designing this breast phantom by performing Monte Carlo simulations, the glandular dose was evaluated and compared with that of a mixed-form phantom. Then, dose evaluation was conducted for current commercial filament materials that could be used to fabricate the phantom by 3-D printing. The results showed that the dose received by the mammary gland was in the range of 1.089-1.237 mGy, and the average difference from that determined using the mixed-form phantom was approximately 1.2 %. Among the filament materials, polylactic acid showed the dose that was the most similar to that of the mammary gland tissue, differing by approximately 2.4 %. Overall, the research results suggest that it is meaningful to evaluate the glandular dose using the developed phantom instead of a mixed-form phantom. Besides, polylactic acid is the most appropriate material for fabricating the mammary gland tissue using a 3-D printer. [ABSTRACT FROM AUTHOR]

In this paper, the preparation and the measurement of a set of human breast phantoms for microwave breast imaging (MBI) as a method of tumor detection are presented. The developed artificial breast phantoms have realistic dielectric properties. Homogenous and most realistic heterogeneous breast phantoms have been fabricated based upon 3D structures filled up with different chemical mixtures that imitate the various breast tissue types (skin, healthy fat tissue, glandular tissue, and tumor tissue) regarding permittivity over ultra-wideband frequency band (3.1-10.6 GHz). The primary challenge in fabricating such phantoms is in developing suitable mixtures of materials to emulate those properties across the frequency band of interest in hyperthermia and to fabricate the phantom with realistic anatomy. Once fabricated, the dielectric properties are measured using a dielectric probe connected with a modern vector network analyzer. The measured dielectric is compared to real human breast dielectric properties, and the primary imaging results are presented. The integrated design of the homogenous and heterogeneous phantoms permits to combine the tumor and breast phantoms dynamically for creating a test platform based on MBI systems. The experimental dielectric properties of the phantoms show good agreement with this paper and theoretical results. The phantoms are constructed in such a way that the chosen materials demonstrate the properties to be stable over a long period. The experimental results demonstrate the validity of our proposed phantoms to be used in investigating as a supplement to the real human breast tissue with multiple object and comparatively high-resolution image.

Background: Breast cancer is the most commonly diagnosed malignancy in females and frequently requires core needle biopsy (CNB) to guide management. Adequate training resources for CNB suffer tremendous limitations in reusability, accurate simulation of breast tissue, and cost. The relatively recent advent of 3D printing offers an alternative for the development of breast phantoms for training purposes. However, the feasibility of this technology for the purpose of ultrasound (US) guided breast intervention has not been thoroughly studied. Methods: We designed three breast phantom models that were printed in multiple resins available through Stratasys, including VeroClear, TangoPlus and Tissue Matrix. We also constructed several traditional breast phantoms using chicken breast and Knox gelatin for comparison. These phantoms were compared side-by-side for ultrasound penetrance, simulation of breast tissue integrity, anatomic accuracy, reusability, and cost. Results: 3D printed breast phantoms were more anatomically accurate models than traditional breast phantoms. The chicken breast phantom provided acceptable US beam penetration and material hardness for simulation of human breast tissue integrity. Sonographic image quality of the chicken breast phantom was the most accurate overall. The gelatin-based phantom also had acceptable US beam penetration and image quality; however, this material was too soft and poorly simulated breast tissue integrity. 3D printed phantoms were not visible under US. Conclusions: There is a large unmet need for a printable material that is truly compatible with multimodality imaging for breast and other soft tissue intervention. Further research is warranted to create a realistic, reusable and affordable material to 3D print phantoms for US-guided intervention training. [ABSTRACT FROM AUTHOR]

Objective: High-resolution dedicated breast positron emission tomography (dbPET) can visualize breast cancer more clearly than whole-body PET/computed tomography (CT). In Japan, the combined use of dbPET and whole-body PET/CT is necessary in indications for health insurance. Although several clinical studies have compared both devices, a physical evaluation by the phantom test has not been reported. The aim of this study was to compare the ability of ring-shaped dbPET and whole-body PET/CT using a common phantom with reference to the Japanese guideline for the oncology 18F-fluorodeoxyglucose (FDG)-PET/CT data acquisition protocol.Methods: A cylindrical breast phantom with four spheres of different diameters (16, 10, 7.5, and 5 mm) filled an FDG solution at sphere-to-background radioactivity ratios (SBRs) of 2:1, 4:1, and 8:1 was prepared. Images were then acquired by whole-body PET/CT and subsequently by dbPET. The reconstructed images were visually evaluated and the coefficient of variation and uniformity of the background (CVbackground and SDΔSUVmean), percentages of contrast and background variability (%QH,5mm and %N5mm), and their ratio (%QH,5mm/N5mm), and relative recovery coefficient were compared with the standards defined in the protocol for whole-body PET/CT.Results: The parameters were calculated at an SBR of 8:1, which was the only SBR in which a 5-mm sphere was visible on both devices. The standards were defined as < 10% for CVbackground, ≤ 0.025 for SDΔSUVmean, < 5.6% for %N5mm, > 2.8 for %QH,5mm/N5mm, and > 0.38 for the relative recovery coefficient of the smallest sphere (10 mm in diameter) in the protocol for whole-body PET/CT (the %QH,5mm was not determined for that protocol); the respective values were 6.14%, 0.024, 4.55%, 3.66, and 0.33 for dbPET and 2.21%, 0.021, 3.11%, 1.72, and 0.18 for PET/CT. The QH,5mm was 16.67% for dbPET and 5.34% for PET/CT. The human images also showed higher lesion-to-background contrast on dbPET than on PET/CT despite the noisier background observed with dbPET.Conclusion: The common phantom study showed that the background was noisier and that the contrast was much higher in the dbPET image than in the PET/CT image. The acquisition protocol and standards for dbPET will need to be different from those used for whole-body PET/CT. [ABSTRACT FROM AUTHOR]

Objective(s): Breast cancer is a fatal disease and the leading cause of mortality in women. Radiofrequency hyperthermia is an approach to the treatment of cancer cells through increasing their temperature. The present study aimed to investigate breast tumor ablation via radiofrequency hyperthermia in the presence and non-presence states of magnetite nanoparticles and assess the effects of magnetite nanoparticles on breast cancer treatment in hyperthermia. Materials and Methods: Radius hemisphere geometry (5 cm) was designed, which was similar to an actual breast based on the fat tissues, glandular tissues as a semi-oval embedded in the hemisphere, and a radius sphere (1 cm) as a tumor region inside. After utilization in a three-dimensional printer, each layer of the phantom was filled with a proper combination of oil-gelatin with similar dielectric and thermal properties to an actual breast. To evaluate the effects of the magnetite nanoparticles, three weights of the magnetite were added to the tumor region (0.01, 0.05, and 0.1 g). Finally, the phantom was placed in a radiofrequency device with the frequency of 13.56 MHz. Results: Temperature differences were measured at four different points of the phantom. The power and time in the treatment were estimated at 40 watts and five minutes, respectively. The temperature and specific absorption rate plots were obtained for all the states in several graphs for five minutes. The results showed that the heat generation with the utilization of the magnetite state was higher by approximately 2.5-7°C compared to the state without magnetite. Furthermore, the temperature of 0.05 gram of magnetite indicated that without causing damage in the healthy tissues, the entire tumor region could attain adequate heat uniformly (6.1-6.4°C). Conclusion: Therefore, it could be concluded that 0.05 gram of magnetite could cause ablation in the entire tumor region. [ABSTRACT FROM AUTHOR]

The virtual image system is a key component of virtual clinical trials (VCTs) which can be utilized to evaluate and improve medical imaging devices. The main limitation of VCTs in the Chinese female breast is the lack of detailed structure in the breast model employed in the Chinese specification for testing of quality control in mammography. In this paper, based on Chinese female breast parameters, detailed breast phantoms with different glandularity (fatty, glandular, dense) and compressed breast thicknesses (CBT) (2–7 cm) were generated. Digital mammography (DM) and digital breast tomosynthesis (DBT) projections for these phantoms were simulated with clinical system configuration. Compressed breast volumes were reconstructed through DBT projections with different angles. Power spectrum analysis and fractal dimension measurement were applied for simulated and clinical images. The results show that the average power law exponents and standard deviation (DM, DBT) for clinical and simulated images were (3.26 ± 0.29, 3.33 ± 0.42) and (3.63 ± 0.25, 3.18 ±0.36) respectively. The average fractal dimensions and standard deviation (DM, DBT) for clinical and simulated images were (2.36 ± 0.03, 2.41 ± 0.05) and (2.10 ± 0.01, 2.26 ± 0.06) respectively. We constructed two virtual imaging systems for DM and DBT and obtained the imaging data based on the three-dimensional (3D) detailed breast phantoms. These results indicate that the texture indexes of simulated images are similar to that of the clinical images, and validate that these breast phantoms are suitable for imaging in VCTs requiring realistic anatomy with the Chinese female population. Results also show that the values of power law exponents for clinical and simulated images in DM and DBT are positively correlated with the value of breast glandularity, but the values of fractal dimensions keep steady for different glandularity. • Constructed mammography & breast tomosynthesis imaging system. • Breast phantoms with detailed structure for Chinese females. • Simulated images' texture indexes similar to clinical images. • Breast phantoms meet dosimetry & imaging requirements. • Good start for VCTs image generation with realistic anatomy. [ABSTRACT FROM AUTHOR]