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In this work, the deformation of bilateral breasts was investigated with an established hybrid model to predict the nipple movement specifically for senior women during yoga exercise. A motion capture system was used to collect the displacement of 10 markers on the breasts from 11 senior women (average age of 62) during yoga practice and then the data were analyzed by integrating the absolute grey relation analysis (AGRA) and extreme learning machine (ELM). The right and left breasts had the maximum motion amplitude in the horizontal direction but they were respectively featured with contraction and extension during yoga practice. AGRA showed that the nipple motion was highly associated with the vertical region above the nipple for the left breast but the parallel region along with the nipple for the right breast. The ELM model is able to predict the nipple movement within tolerable error (∼0.0037). This study lays a foundation for a better understanding of ageing breast kinematics during yoga poses with limited practical experiments. Besides, the accurate and efficient results can be used not only for yoga pose instruction but also for ergonomic sports bra design.

A well-fitting bra provides adequate and exceptional support of the breasts and the desirable body shape for the wearer but would not exert excessive pressure onto the breasts. Among the different design features of bras, the materials selected for the bra cups are a key element for enhancing breast support and improving the perceived comfort. This paper proposes a subject-specific model based on numerical simulation to investigate the influence of different types of bra cup materials on the shape of the breasts and amount of pressure on the breasts. The study comprises three phases. The first phase is the development of a subject-specific contact model and simulation of the bra-wearing process. The second phase is the construction and analysis of three models with different bra cup materials (knitted, woven and foam) to compare their shaping effects on the breasts and the corresponding amount of applied contact pressure. The third phase uses the validated numerical model to simulate the use of a series of virtual bra cup materials, their impact on the shape of the breasts, and the associated bra pressure. It is found that a stiffer fabric has a better performance in reshaping the breasts and reducing the amount of pressure from the straps onto the neck for a halter-neck bra but distributes a higher amount of pressure at the bottom part of the breasts. An overall better performance of reshaping the breasts is achieved by increasing the tensile strength of the bra cup material. Nevertheless, the small change in the shaping effects can be negligible after the Young’s modulus reaches about 1.5 MPa. Among the four measured variables, it is more useful to measure the gathering of the breasts and depth of cleavage than the lifting of the breasts to determine the amount of breast deformation caused by a bra. The newly developed finite element model for contact analysis in this study provides a better understanding on the interactive process between the breasts and the bra by predicting the deformation within a variance of 6.8 % in comparison to the experimental results of the contact pressure with the same trend and magnitude. Numerical simulations can therefore facilitate decisions on the type of fabric used for bra designs that provide optimal fabric pressure and other stretchable apparel products that take both the shaping effect and wear comfort into consideration.

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.

Background - Quantification of the magnitude of skin strain in different regions of the breast may help to estimate possible gravity-induced damage whilst also being able to inform the selection of incision locations during breast surgery. The aim of this study was to quantify static skin strain over the breast surface and to estimate the risk of skin damage caused by gravitational loading.Methods - Fourteen participants had 21 markers applied to their torso and left breast. The non-gravity breast position was estimated as the mid-point of the breast positions in water and soybean oil (higher and lower density than breast respectively). The static gravity-loaded breast position was also measured. Skin strain was calculated as the percentage extension between adjacent breast markers in the gravity and non-gravity loaded conditions.Findings - Gravity induced breast deformation caused peak strains ranging from 14 to 75% across participants, with potentially damaging skin strain (> 60%) in one participant and skin strains above 30% (skin resistance zone) in a further four participants. These peak strain values all occurred in the longitudinal direction in the upper region of the breast skin. In the latitudinal direction, smaller-breasted participants experienced greater strain on the outer (lateral) breast regions and less strain on the inner (medial) breast regions, a trend which was reversed in the larger breasted participants (above size 34D).Interpretation - To reduce tension on surgical incisions it is suggested that preference should be given to medial latitudinal locations for smaller breasted women and lateral latitudinal locations for larger breasted women.

The exact delineation of tumour boundaries is of utmost importance in the planning of cancer therapy, either surgery or pre- or post-operative radiation treatment. In the case of breast cancer one of the most advanced modalities is magnetic resonance imaging (MRI). Although MRI scans provide wealth of information about the structure of a tumour and the surrounding tissues, the data obtained represent the patient in a prone position, with breast, in a coil while surgery is performed in a supine position, on lying breast. There is no doubt that a patient's breast in both positions has a different shape and that this influences the intra-breast relations. Our present preliminary study introduces a simple breast model developed from prone images. The model should be built rapidly and by a simple procedure, based only on essential structures, and the goal is to prove its usefulness in treatment planning.

In this paper, two estimation problems are tackled. Firstly, the robust estimation of the external contour of the breast, using data from a Radio-Frequency (RF) Ultra-Wide Band (UWB) scan. Secondly, the registration between the RF breast scan and the breast scan using a 3D stereographic infrared camera. The bi-modality data registration is meant for controlled patient positioning and breast deformation during the RF breast examination.

It has been a long-standing problem in the engineering design of bra for optimal support and shaping due to the difficulty of quantifying the hyper-elastic properties of human breasts. The objective of this study is to determine an optimal approach to obtain the non-linear properties of breast soft tissues and the corresponding deformations during motions. The Mooney-Rivlin material parameters of the breasts in-vivo were verified through an optimization process that involved iteratively changing the material coefficients with the integration of static and dynamic finite element models. Theoretical equations of a rigid-flexible coupled system during the motion of forward-leaning were established with gravitational, centrifugal and Coriolis forces to simulate the dynamic deformation of the flexible breasts. The resultant, optimally generated, coefficients of the Mooney-Rivlin hyperelastic material type for the breast were found. This new set of breast material coefficients was verified by finite element analysis of the breast deformation during forward-leaning and running movement. The method proposed in this study provides an effective way to determine the breast properties for predicting breast deformation and analysis of the bra-breast contact mechanism and thus, improving the design of bras.

Increasing interest in multimodal breast cancer diagnosis has led to the development of methods for MRI to X-ray mammography registration to provide direct correlation of modalities. The severe breast deformation in X-ray mammography is often tackled by biomechanical models, which however have not yet brought the registration accuracy to a clinically applicable level. We present a novel registration approach of MRI to X-ray tomosynthesis. Tomosynthesis provides three-dimensional information of the compressed breast and as such has the ability to open new possibilities in the registration of MRI and X-ray data. By bundling the 3D information from the tomosynthesis volume with the 2D projection images acquired at different measuring angles, we provide a correlation between the registration error in 3D and 2D and evaluate different 3D- and 2D-based similarity metrics to drive the optimization of the automated patient-specific registration approach. From the preliminary study of four analysed patients we found that the projected registration error is in general larger than the 3D error in case of small registration errors in the cranio-caudal direction. Although both image shape and intensitybased 2D similarity metrics showed a clear correlation with the 2D registration error at different projection angles, metrics that relied on the combined 2D and 3D information yielded in most of the cases the minimal registration error and as such had better performance than similarity metrics that rely only on the shape similarity of volumes.

Summary:. Breast-conserving therapy, where radiotherapy is performed after partial mastectomy, is a widely used surgical method that can preserve most of the breast tissue without increasing the recurrence rate of breast cancer. However, without reconstruction, asymmetry of the breast occurs due to the tissue defect and radiation fibrosis, producing in poor cosmetic results. In this case study, we performed staged prosthetic breast reconstruction combined with fat grafting for severe depressive deformation of the breast after breast-conserving therapy. The first surgery involved insertion of a tissue expander and fat grafting, second surgery was the reduction of injected saline volume and fat grafting, and third surgery involved exchange for an implant and fat grafting. The skin in the depressed area, which had atrophied, became soft and flexible; deformation was also improved, and the patient was satisfied with the aesthetic outcome. It is expected that fat grafting will fertilize and qualitatively improve the damaged tissue due to irradiation, reducing the complications related to the tissue expander and implant. We believe that it will be possible to correct a breast deformity after breast-conserving therapy using a tissue expander and implant, which had not been considered as a solution. The results showed that the present method can be an option for delayed reconstruction after breast-conserving therapy.

In this paper, new model had been proposed applied on real experimental elastography images. These images were for different cases of breast cancers (benign and malignant). In this model, the elastography technique has been applied depending on imaging the breast deformation after applying multi forces on the breast. These forces had been applied breast’s model after constructing for different positions and sizes of the tumors within the breast with practical cases. The collected results had been compared with in vitro experimental results and had shown the accuracy of this model.

Breast cancer treatments can have a negative impact on breast aesthetics, in case when surgery is intended to intersect tumor. For many years mastectomy was the only surgical option, but more recently breast conserving surgery (BCS) has been promoted as a liable alternative to treat cancer while preserving most part of the breast. However, there is still a significant number of BCS intervened patients who are unpleasant with the result of the treatment, which leads to self-image issues and emotional overloads. Surgeons recognize the value of a tool to predict the breast shape after BCS to facilitate surgeon/patient communication and allow more educated decisions; however, no such tool is available that is suited for clinical usage. These tools could serve as a way of visually sensing the aesthetic consequences of the treatment. In this research, it is intended to propose a methodology for predict the deformation after BCS by using machine learning techniques. Nonetheless, there is no appropriate dataset containing breast data before and after surgery in order to train a learning model. Therefore, an in-house semi-synthetic dataset is proposed to fulfill the requirement of this research. Using the proposed dataset, several learning methodologies were investigated, and promising outcomes are obtained.

Purpose To evaluate intrafraction variability and deformation of the lumpectomy cavity (LC), breast, and nearby organs. Methods and Materials Sixteen left-sided postlumpectomy and 1 bilateral breast cancer cases underwent free-breathing CT (FBCT) and 10-phase 4-dimensional CT (4DCT). Deformable image registration was used for deformation analysis and contour propagation of breast, heart, lungs, and LC between end-exhale and end-inhale 4DCT phases. Respiration-induced motion was calculated via centroid analysis. Two planning target volumes (PTVs) were compared: PTV FBCT from the FBCT volume with an isotropic 10 mm expansion (5 mm excursion and 5 mm setup error) and PTV 4DCT generated from the union of 4DCT contours with isotropic 5 mm margin for setup error. Volume and geometry were evaluated via percent difference and bounding box analysis, respectively. Deformation correlations between breast/cavity, breast/lung, and breast/heart were evaluated. Associations were tested between cavity deformation and proximity to chest wall and breast surface. Results Population-based 3-dimensional vector excursions were 2.5 ± 1.0 mm (range, 0.8-3.8 mm) for the cavity and 2.0 ± 0.8 mm (range, 0.7-3.0 mm) for the ipsilateral breast. Cavity excursion was predominantly in the anterior and superior directions (1.0 ± 0.8 mm and −1.8 ± 1.2 mm, respectively). Similarly, for all cases, LCs and ipsilateral breasts yielded median deformation values in the superior direction. For 14 of 17 patients, the LCs and breast interquartile ranges tended toward the anterior direction. The PTV FBCT was 51.5% ± 10.8% larger ( P 4DCT . Bounding box analysis revealed that PTV FBCT was 9.8 ± 1.2 (lateral), 9.0 ± 2.2 (anterior–posterior), and 3.9 ± 1.8 (superior–inferior) mm larger than PTV 4DCT . Significant associations between breast and cavity deformation were found for 6 of 9 axes. No dependency was found between cavity deformation and proximity to chest wall or breast surface. Conclusions Lumpectomy cavity and breast deformation and motion demonstrated large variability. A PTV 4DCT approach showed value in patient-specific margins, particularly if robust interfraction setup analysis can be performed.

BACKGROUND The latissimus dorsi muscle flap represents a valuable option in breast reconstruction but can result in postoperative twitching and retraction, discomfort, arm movement limitations, and breast deformation. These complications can be avoided by denervation of the thoracodorsal nerve; however, the optimal method of nerve management is unknown. This study presents the authors' experience with the outcomes of latissimus dorsi flaps for breast reconstruction in the light of thoracodorsal nerve management strategies. METHODS The authors retrospectively collected data from 74 patients who underwent partial or total breast reconstruction with a latissimus dorsi flap alone or with an implant between January of 1999 and October of 2011. Follow-up data were collected at 12 and 24 months postoperatively. RESULTS In 56 patients (75.7 percent), the latissimus dorsi muscle was denervated at the time of surgery, whereas the thoracodorsal nerve remained intact in 18 patients (24.3 percent). No partial or total flap loss was observed. At 12 and 24 months' follow-up, all patients with an intact thoracodorsal nerve showed twitching of the muscle, and 50 percent and 67.9 percent, respectively, of the denervated patients showed twitching (p < 0.001). No patient had twitching if more than 4 cm of nerve was excised at 12 or 24 months postoperatively, and the length of nerve resection was predictive of the presence of twitching. CONCLUSION Denervation of the latissimus dorsi is a safe and reliable procedure that should be performed at the time of breast reconstruction and should include more than 4 cm to achieve a nontwitching breast with a stable volume and shape.

Breast tissue deformation has recently gained interest in various medical application. The recovery of large deformation caused by gravity or compression loads and image registration is non-trivial task. The need arise to estimate large breast deformation, which can mimic natural body movement caused by examinations or surgery. Finite element methods (FEM) have been widely applied in this field. In this work we present the current breast deformation modelling trend. The meaningful applications and essentials examinations are described. The modelling software and basic techniques are presented.

Increasing number of people are suffering from cancer these days. The highest incidence among women is breast cancer. One of the main sources of diagnostic information is Magnetic Resonance Imaging (MRI). Another one is Positron Emission Tomography with Computer Thomography (PET-CT). Both examinations take place in different patient positions (prone and supine respectively). The only way to obtain complete diagnostic information is to bring MRI images into PET-CT space and compare both. Our preliminary studies focus on creating a simple, deformable finite element model of the breast. Proposed algorithm allows to obtain breast model in supine position, created from MRI images obtained in prone position.

PurposeThe breast is composed of two main types of soft tissues: glandular tissue and adipose tissue. Wearing a brassiere makes them deform easily. In order to design comfortable brassieres by which the body shape is adjusted, it is important to clarify the relationship between the breast deformation and the internal structure of the breast. The purpose of this paper is to assess a method to determine the structure inside the breast. Breast shape comparison was performed to assess the relationship between the external deformation caused by wearing a brassiere and the internal structure of the breast.Design/methodology/approachThe subjects were five adult females. The breast MRI imaging in the sitting position was carried out using the vertical MRI systems under bare breasts condition and under wearing a brassiere condition. By creating 3D images from the MRI images obtained, the internal structure of the breast was determined. The 3D images under the wearing brassiere conditions were superimposed on the images under the bare breasts condition, and the breast shape comparison was performed to assess the relationship between the external deformation caused by wearing a brassiere and the internal structure of the breast.FindingsThe internal 3D structure of the breast, which had been unmeasurable in the sitting position, could be obtained using the vertical MRI system. Additionally the effect of wearing a brassiere on the breast was assessed in terms of the relation between the external deformation and the internal structure of the breast.Originality/valueThis paper's results can be utilized for human body model in simulation, and to provide fruitful data for the design of comfortable brassieres.

Breast cancer is the most common cancer in female. Accuracy of breast biopsy intervention is necessary for the certain breast cancer diagnosis. Many breast navigation systems have been developed in the past time to cope with this uncertainty, however, the worthwhile accuracy could not yet reach due to the breast deformation during the intervention. The concept of breast mathematical model to simulate breast deformation and guide the breast biopsy intervention is proposed in this paper. The real-time and the accuracy of the model are the critical requirements to use the model with the breast biopsy navigation. The breast model is constructed by simplify the continuous breast tissues into finite point-masses system with specific stiffness and damp on linkages between masses. The mesh alignments are arbitrary base on evidence of the tissue's microstructure. The mass-spring method is used for implementation the point-masses and their linkages. The experimental system simulation for using model with real-time breast biopsy navigation was setup on a constructed massspring system of 2D breast phantom. The experiment was performed to proof the core concept of the proposed breast model to be use as a key component for our full-robotic breast biopsy navigation.

The purpose of this research was to focus on the study of the morphology of the female bust during the physical activity to improve comfort and aesthetics of bras. From a health point of view, it i...

This study was performed to explore and compare the dosimetric variance caused by respiratory movement in the breast during forward-planned IMRT after breast-conserving surgery. A total of 17 enrolled patients underwent the 3DCT simulation scans followed by 4DCT simulation scans during free breathing. The treatment planning constructed using the 3DCT images was copied and applied to the end expiration (EE) and end inspiration (EI) scans and the dose distributions were calculated separately. CTV volume variance amplitude was very small (11.93 ± 28.64 cm(3)), and the percentage change of CTV volumes receiving 50 Gy and 55 Gy between different scans were all less than 0.8%. There was no statistically significant difference between EI and EE scans (Z =-0.26, P = 0.795). However, significant differences were found when comparing the Dmean at 3DCT planning with the EI and EE planning (P = 0.010 and 0.019, respectively). The homogeneity index at EI, EE and 3D plannings were 0.139, 0.141 and 0.127, respectively, and significant differences existed between 3D and EI, and between 3D and EE (P = 0.001 and 0.006, respectively). The conformal index (CI) increased significantly in 3D treatment planning (0.74 ± 0.07) compared with the EI and EE phase plannings (P = 0.005 and 0.005, respectively). The V30, V40, V50 and Dmean of the ipsilateral lung for EE phase planning were significantly lower than for EI (P = 0.001-0.042). There were no significant differences in all the DVH parameters for the heart among these plannings (P = 0.128-0.866). The breast deformation during respiration can be disregarded in whole breast IMRT. 3D treatment planning is sufficient for whole breast forward-planned IMRT on the basis of our DVH analysis, but 4D treatment planning, breath-hold, or respiratory gate may ensure precise delivery of radiation dose.

The paper aims to study the behaviour of female busts when static or dynamic and must take into account the different biological components of the breast. The numerical simulation of the breast deformability enables the development of new techniques for corsetry or new medical equipment, especially for the detection of breast cancer. In this study, a hyperelastic model of the static behaviour of the bust based on an experimentally-finite element simulation that takes into account the components (skin, fat, glands or fibres and suspensory ligaments of Cooper) responsible for the actual breast deformability under the influence severity is given.

Biomechanical models of the breast can be used to co-locate information between the various medical images to identify tumour locations, while also providing the ability to predict their locations during surgical procedures. We have created subject-specific, heterogeneous 3D finite element (FE) models of breast biomechanics to provide the ability to predict breast deformation under different loading conditions. We have verified the applicability of such modelling for simulating the prone to supine reorientation of the breast and obtained good agreement to ground-truth supine images obtained from breast MRI. In particular, we highlight the importance of modelling the pectoral muscles for gravity loading simulations.

In this research project, we have developed mathematical model of breast deformation to simulate breast compression during mammographic imaging. We have developed two types of mammogram registration methods: magnetic resonance imaging (MRI) guided registration and generic registration. Datasets have been constructed to validate the developed registrations methods. Mammogram registrations have been performed on concurrent mammograms using MRI guided and generic registration method, respectively. Also both registration methods have been applied onto temporal mammograms. Promising evaluation results demonstrate feasibility of the developed mammogram registration methods. The results also demonstrate that the developed registration methods would be very helpful in mammogram interpretation for improving accuracy of detection and diagnosis of breast cancer.

Registering features in multiple mammographic views is an important technique to improve breast cancer detection rate. However, nonrigid breast deformation during X-ray imaging poses a severe challenge to the conventional 2D registration methods. We present a method that utilizes a 3D model to facilitate two-view registration by predicting breast deformation. At first, a finite element model of a breast is constructed using its MRIs. The model is capable of simulating both compression and decompression. Feature registration is then accomplished through a series of projections and compression-decompression operations. Experiments using real patient data demonstrate that a mammographic feature can be successfully registered from one view to another

A breast tumor is visible by a passive microwave radiometer if it changes the radiometer output of a healthy breast to an extent that overcomes the radiometric resolution. The characteristics of a new dual-band near-field radiometer are exposed. The deformation by an antenna pressed against the breast lowers the distance of a subsurface tumor from the contacted surface improving the tumor radiometric visibility. We show this result by modeling breast deformation, temperature and corresponding radiometer output both in the presence of a tumor and in its absence. For a 25% net breast deformation, a tumor of 10 mm diameter is visible by a 0.1degC radiometer and a 3 cm aperture antenna when it is 4 cm deep in the undeformed breast.

We investigated nonrigid co-registration of PET and MR breast images to improve diagnostic specificity in difficult-to-interpret mammograms, and ultimately to avoid biopsy. A deformable breast model based on a finite-element method (FEM) was employed. The FEM "loads" were taken as the observed intermodal displacements of several fiducial skin markers placed on the breast and visible in PET and MRI. The analogy between orthogonal components of the displacement field and the temperature differences in a steady-state heat transfer (SSHT) in solids was adopted. The model allows estimation of the intermodal breast deformation for every location within the breast. To test our model, an elastic breast phantom with simulated internal "lesions" and external markers was imaged with PET and MRI. We estimated fiducial- and target-registration errors vs. number and location of the fiducials. We established that SSHT approach using external fiducial markers is accurate to within /spl sim/5 mm.

A CAD system for estimating the 3D (three-dimensional) positions of lesions found in two mammographic views is described. The system is an extension of our previous method [Comput. Vis. Image Understand. 83 (2001) 38] which finds corresponding 2D positions in different mammographic views. The method calculates curved epipolar lines by developing a simulation of breast deformation into stereo camera geometry. Using such curved epipolar lines, not only can we determine point correspondences, but can estimate the 3D location of a lesion. In this paper, we first explain the underlying principles and system organisation. The correctness of the 3D positions calculated by the system is examined using a set of breast lesions, which appear both in mammograms and in MRI data. The experimental results demonstrate the clinical promise of the CAD system.

Realistic modelling of breast deformation requires the breast tissue to be segmented into fibroglandular and fatty tissue and assigned suitable material properties. There are a number of breast tissue segmentation methods proposed and used in the literature. The purpose of this study was to validate and compare the accuracy of various segmentation methods and to investigate the effect of the tissue distribution on the segmentation accuracy. Computed tomography (CT) data for 24 patients, both in supine and prone positions were segmented into fibroglandular and fatty tissue. The segmentation methods explored were: physical density thresholding; interactive thresholding; fuzzy c-means clustering (FCM) with three classes (FCM3) and four classes (FCM4); and k-means clustering. Validation was done in two-stages: firstly, a new approach, supine-prone validation based on the assumption that the breast composition should appear the same in the supine and prone scans was used. Secondly, outlines from three experts were used for validation. This study found that FCM3 gave the most accurate segmentation of breast tissue from CT data and that the segmentation accuracy is adversely affected by the sparseness of the fibroglandular tissue distribution.

Virtual clinical trials VCT currently represent key tools for breast imaging optimisation, especially in two-dimensional planar mammography and digital breast tomosynthesis. Voxelised breast models are a crucial part of VCT as they allow the generation of synthetic image projections of breast tissue distribution. Therefore, realistic breast models containing an accurate representation of women breasts are needed. Current voxelised breast models show, in their compressed version, a very round contour which might not be representative of the entire population. This work pretends to develop an imaging framework, based on depth cameras, to investigate breast deformation during mammographic compression. Preliminary results show the feasibility of depth sensors for such task, however post-processing steps are needed to smooth the models. The proposed framework can be used in the future to produce more accurate compressed breast models, which will eventually generate more realistic images in VCT.