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Modeling the events that take place during childbirth requires an integration of morphological features, tissue characteristics, and prediction of the most probable fetal movements according to the inputs submitted to the computational model. The choice of the material properties and constitutive models affect the outputs, and the challenge still points out to how to mathematically describe the pelvic soft tissues if experimental proof is not possible. Several authors explored the modeling of vaginal delivery by focusing on different aspects: the maternal pelvic bones, the fetus position, and head molding, but most of them focused on the effects of vaginal delivery on the pelvic floor muscles. The present chapter reviews the events that occur during childbirth, to better illustrate the features described in a computational reproduction of labor. The focus is set on the results from different numerical simulation approaches, and on the biomechanical analysis of the pelvic floor muscles and fetal head passage.

Although the use of neuroscientific knowledge to investigate marketing issues has been widely discussed, to date, few empirical studies have been published. This study is a first approach in the development of a theory of the perception of brands, which is based on neuroscience. In a Functional Magnetic Resonance Imaging experiment, we stimulated participants with commercial brands’ logos, with and without explicit instructions on how to assess them, in an attempt to capture the real-life experience of evaluating brands. We found common activations in both situations in the medial frontal pole, the paracingulate gyrus, the frontal orbital cortex, the frontal medial cortex, and in the hippocampus. In a general scheme of brands’ perception, we hypothesised a relationship between Theory of Mind and meta-representations, in particular self-reflexive ones: ‘I think about what others are thinking about me’. We suggest that brands have an important social dimension. Brands may function like a social currency, which every individual uses to assess others, and which others are expected to use in their assessments of the individual. Brands are most probably social tools.

Brands are believed to embody emotional, socially relevant and self-related content. In this experiment functional magnetic resonance imaging (fMRI) was used to explore the neural correlates of brands' perception. A common network of brain areas involved in the assessment of brands was found, and brain structures that activated significantly more with positive brands than indifferent ones. The participation of the emotional system was remarkable: every brand was felt in order to be assessed; however only preferred brands activated brain regions supposed to be emotional inducers. There were also activations in the paracingulate gyrus and temporo-parietal junction, brain regions believed to be involved in Theory of Mind. Once more, brands rated as positive elicited activations in the ventral medial frontal pole, which may be attributed to self-relatedness and to the role of brands in self-construal.

• IR–TSE serves as a better source of T1-WI than 3D MPRAGE to segment the striatum and thalamus.

The purpose of this study was to determine the influence of different levels of regular physical exercise on the frequency of urinary incontinence in young nulliparous women from the northern region of Portugal. Participants (n=386) self-reported demographic variables, frequency, and time spent practicing organized exercise per week, as well as completed the International Consultation on Incontinence Questionnaire-Short Form. The level of exercise was calculated based on the time (in minutes) usually spent per week in organized exercise. 19.9% of Portuguese nulliparous women reported incontinence symptoms. Considering the distribution of urinary incontinence among the different quartiles of organized exercise, women from the 4(th)quartile (those who train for competitive purposes) demonstrated highest relative frequency (p=0.000) and a 2.53 greater relative risk to develop (95% CIs,1.3-2.7) incontinence compared to women from the 1(st) quartile (inactive). Women who practice exercise for recreational purposes (2(nd) and 3(rd) quartiles) did not show significant differences in the urinary incontinence prevalence and relative risk of developing it compared to women from the 1(st) quartile. The results showed that women participating in organized exercise involving high volume training for competition are potentially at risk of developing urinary incontinence, although organized exercise undertaken without the intent to compete seems to be safe for maintaining urinary continence.

The mechanical characteristics of the female pelvic floor are relevant when explaining pelvic dysfunction. The decreased elasticity of the tissue often causes inability to maintain urethral position, also leading to vaginal and rectal descend when coughing or defecating as a response to an increase in the internal abdominal pressure. These conditions can be associated with changes in the mechanical properties of the supportive structures—namely, the pelvic floor muscles—including impairment. In this work, we used an inverse finite element analysis to calculate the material constants for the passive mechanical behavior of the pelvic floor muscles. The numerical model of the pelvic floor muscles and bones was built from magnetic resonance axial images acquired at rest. Muscle deformation, simulating the Valsalva maneuver with a pressure of 4 KPa, was compared with the muscle displacement obtained through additional dynamic magnetic resonance imaging. The difference in displacement was of 0.15 mm in the antero-posterior direction and 3.69 mm in the supero-inferior direction, equating to a percentage error of 7.0% and 16.9%, respectively. We obtained the shortest difference in the displacements using an iterative process that reached the material constants for the Mooney–Rivlin constitutive model ( c10=11.8 KPa and c20=5.53 E−02 KPa). For each iteration, the orthogonal distance between each node from the group of nodes which defined the puborectal muscle in the numerical model versus dynamic magnetic resonance imaging was computed. With the methodology used in this work, it was possible to obtain in vivo biomechanical properties of the pelvic floor muscles for a specific subject using input information acquired non-invasively.

PURPOSE We aimed to compare two different methods of region of interest (ROI) demarcation and determine interobserver variability on apparent diffusion coefficient (ADC) in breast lesions. METHODS Thirty-two patients with 39 lesions were evaluated with a 3.0 Tesla scanner using a diffusion-weighted sequence with several b-values. Two observers independently performed the ADC measurements using: 1) a small fixed area of 10 mm2 ROI within the area with highest restriction; 2) a large ROI so as to include the whole lesion. Differences were assessed using the Wilcoxon-rank test. Bland-Altman method and Spearman coefficient were applied for interobserver variability and correlation analysis. RESULTS ADC values measured using the two ROI demarcation methods were significantly different for both observers (P = 0.026; P = 0.033). There was no interobserver variability in ADC values using either method (large ROI, P = 0.21; small ROI, P = 0.64). ADC values of malignant lesions were significantly different between the two methods (P < 0.001). Variability in ADC was ≤0.008×10−3 mm2/s for both methods. When using the same method, ADC values were significantly correlated between the observers (small ROI: r=0.990, P < 0.001; large ROI: r=0.985, P < 0.001). CONCLUSION The choice of ROI demarcation method influences ADC measurements. Small ROIs show less overlap in ADC values and higher ADC reproducibility, suggesting that this method may improve lesion discrimination. Interobserver variability was low for both methods.

Pelvic floor injuries during vaginal delivery are considered a significant risk factor to develop pelvic floor dysfunction. The molding of the fetus head during vaginal delivery facilitates the labor progress, since it adjusts to the birth canal geometry. In this work, a finite element model was used to represent the effects induced by the passage of the fetus head on the pelvic floor. The numerical model used for this simulation included the pelvic floor muscles attached to the bones, and a fetus body. The model of the fetus head included the skin and soft tissues, the skull with sutures and fontanelles, and the brain. The fetus head movements during birth in vertex position were simulated: descent, internal rotation and extension. Two models of the fetus head were compared: a rigid and a deformable one, with the inclusion of the cranial sutures. The influence of the fetus head molding on the pelvic floor muscles was analyzed by evaluating their reaction forces, stretch, and stress and strain fields. Additionally, anatomical indices for the molding of the fetal skull were obtained and compared with clinical data. The passage of the deformable fetus head through the birth canal leads to a reduction of 17.3% on the reaction forces on the pelvic floor muscles when compared to the ones of a rigid head. Furthermore, the fetus head molding implies inferior resistance to rotation resulting in a reduction of 1.86% in muscle stretching. Quantitative evaluation of the fetus head molding showed good agreement with clinical experiments.

Many diffusion models have been proposed in order to obtain more information from breast tumor tissues through Magnetic Resonance Imaging (MRI) (1). The Gamma distribution (GD) may model MRI signal decay based on a statistical approach. This model considers the Theta parameter, which indicates the statistical dispersion of the distribution, and the k parameter, which is responsible for the probability distribution shape. If Theta shows higher values, then there will be a more spread out distribution and if k shows lower values the distribution shape will be more affected, which would be expected in malignant tumors due to tissue heterogeneity (1). The purpose of this study was to evaluate if GD model is capable of distinguishing between different breast tumors. Materials and Methods: In this study 85 breast tumor lesions were analyzed, including 17 benign lesions (Fibroadenoma, FA) and 68 malignant lesions (43 Invasive Ductal Carcinomas, IDC 19 Invasive Lobular Carcinomas, ILC and 6 Ductal Carcinoma in situ, CDIS). Informed consent was obtained for all patients. Data were acquired using a 3T MRI scanner with a dedicated breast coil and a DWI sequence with 3 orthogonal diffusion gradient directions and 8 b values between 0 and 3000s/mm2. Theta and k parameters were acquired from fitting data to the GD model, and mean values were obtained to compare between benign and malignant lesions, and between histological types. Non-parametric statistics were used (α=0.05). Results and Discussion: Significantly lower Theta and higher k values were observed in benign lesions ((0.65±0.43)×10−3mm2/s, 4.29±1.90, respectively) when compared to malignant lesions ((0.97±0.50)×10−3mm2/s, 1.23±0.52, respectively). It was also possible to differentiate FA from IDC lesions with both Theta and k probably due to IDC heterogeneity, which restricts diffusion. Unlike other diffusion model parameters, these were able to differentiate FA and ILC, and FA and CDIS lesions, suggesting that the GD model could bring advantages over other diffusion models in characterizing breast tumors. This study was partly funded by Fundacao para a Ciencia e Tecnologia (FCT) under the grant PEst-OE/SAU/UI0645/2014.

Changes in the morphology of the pelvic floor muscles (PFM) or in their attachment points can cause functional weakness, especially when during effort. When there is the need to counteract the increase in intra-abdominal pressure, urinary leakage may occur, which may in turn be related to the reduction of Moment of Inertia (MOI). We aimed to test the relation between muscle morphology, MOI and muscle displacement during computational simulation of valsalva maneuver. For that purpose, axial MRI images from five athletes were acquired. Measures of muscle thickness and area were taken, and the MOI and cross-sectional area were calculated using segmentation splines from the Inventor® software. Additionally, biomechanical models were through numerical simulation of valsalva maneuver using the Abaqus® software. The results showed an association between MOI and muscle displacement (p=0.037; r=-0.900) and thickness (p=0.037; r=0.900). Muscle area showed no significative association with the displacement during valsalva maneuver.

Physical activity has been promoted to all ages due to the benefits to health and as a tool to compensate for a sedentary lifestyle. Since the pelvic floor muscles have the function of keeping the sphincter functions and it were localized as a “floor” for the abdominal viscera. Maintain this muscles “healthy” is the great importance. It is known that some exercises can promote damage on the pelvic floor muscles. The impact of exercise on urinary incontinence has been previously considered, but not in a biomechanical perspective. Strengthening exercises performed through pelvic floor muscles contractions are the basis of physiotherapy treatment. The aim of this study was to verify whether practitioners of high-impact sports have differences in morphology and behavior of pelvic floor muscles when compared with low-impact activities practitioners. The results showed thickness differences at the level of midvagina between the swimmer and the trampolinist women. Additionally, differences in pubovisceral muscle behavior during maneuvers that increase intra-abdominal pressure were found. Further studies are required in this field to understand the impact of female training, and in what way its biomechanics related to urinary incontinence symptoms.

Computational simulation of degeneration or damage on the structures that sustain the female pelvic organs may point to how they behave in real-life conditions. This work evaluated the effect of the impairment of female pelvic ligaments by means of numerical simulation considering rest and valsalva maneuver conditions. The model included the pelvic organs and several support structures, identified on magnetic resonance images from a young healthy female. For each tissue, material properties were obtained in the literature, and the best constitutive model was chosen for each structure. The displacement of the pelvic organs was assessed for normal ligaments, and also when their impairment was simulated by individually reducing their stiffness. The pelvic organs evidenced increased displacement when considering the damaged ligaments, similarly to what was found in previous imaging evidence. This model was suited for assessing ligaments damage. This is an important issue when simulating aging or trauma of the pelvic support structures.

The biomechanical properties of the female pelvic floor tissues, such as muscles, fascia or ligaments are relevant when explaining pelvic disorders, since these may result from changes in the properties of those tissues. The aim of this study is to understand the influence of pelvic organ prolapse (POP) on the passive biomechanical properties of the pelvic floor muscles. For this purpose, magnetic resonance images at Valsalva maneuver were used, and an inverse finite element analysis technique was applied. The numerical models of the pubovisceralis muscle and pelvic bones were built from axial magnetic resonance images acquired at rest. The numerical simulation was based on the finite element method (FEM), by which the material constants were determined for three different constitutive models (Neo-Hookean, Mooney–Rivlin and Yeoh). The ratio between the values of the material constants for women with and without prolapse was approximately 43% for the parameter [Formula: see text] in the Neo-Hookean constitutive model, 57% and 24% for [Formula: see text] and [Formula: see text] in the Mooney–Rivlin constitutive model, and 35%, 21% and 14% for [Formula: see text], [Formula: see text] and [Formula: see text] in the Yeoh constitutive model. For the three constitutive models, the mean values of the material properties related with stiffness were higher for the muscles of women with POP. These increases in stiffness are in line with other experimental works involving vaginal tissue, which showing that the elasticity module is significantly higher in the prolapsed tissue when compared with normal tissue. The present work presents a noninvasive methodology based on the application of the FEM, which allows the establishment of a relationship between the stiffness of the pelvic floor muscles of women with POP and without this pathology.

Excessive mobility of the bladder neck and urethra are common features in stress urinary incontinence. We aimed at assessing, through computational modelling, the bladder neck position taking into account progressive impairment of the pelvic ligaments. Magnetic resonance images of a young healthy female were used to build a computational model of the pelvic cavity. Appropriate material properties and constitutive models were defined. The impairment of the ligaments was simulated by mimicking a reduction in their stiffness. For healthy ligaments, valsalva maneuver led to an increase in the α angle (between the bladder neck-symphysis pubis and the main of the symphysis) from 91.8° (at rest) to 105.7°, and 5.7 mm of bladder neck dislocation, which was similar to dynamic imaging of the same woman (α angle from 80° to 103.3°, and 5mm of bladder neck movement). For 95% impairment, they enlarged to 124.28° and 12 mm. Impairment to the pubourethral ligaments had higher effect than that of vaginal support (115° vs. 108°, and 9.1 vs. 7.3mm). Numerical simulation could predict urethral motion during valsalva maneuver, for both healthy and impaired ligaments. Results were similar to those of continent women and women with stress urinary incontinence published in the literature. Biomechanical analysis of the pubourethral ligaments complements the biomechanical study of the pelvic cavity in urinary incontinence. It may be useful in young women presenting stress urinary incontinence without imaging evidence of urethral and muscle lesions or organ descend during valsalva, and for whom fascial damage are not expected.

In breast diffusion-weighted imaging (DWI), the apparent diffusion coefficient (ADC) is used to discriminate between malignant and benign lesions. As ADC estimates can be affected by the weighting factors, our goal was to determine the optimal pair of b-values for discriminating breast lesions at 3.0 T.152 females with 157 lesions (89 malignant and 68 benign) underwent breast MRI, including a DWI sequence sampling six b-values 50, 200, 400, 600, 800 and 1000 s mm(-2). ADC values were computed from different pairs of b-values and compared with ADC obtained by fitting the six b-values using a mono-exponential diffusion model (ADCall). Cut-off ADC values were determined and diagnostic performance evaluated by receiver operating characteristic analysis using Youden statistics. Mean ADCs were determined for normal tissue and lesions. Differences were evaluated by lesion and histological types.Considering the cut-off values 1.46 and 1.49 × 10(3)mm(2) s(-1), the pairs 50, 1000 and 200, 800 s mm(-2) showed the highest accuracy, 77.5% and 75.4% with areas under the curve 84.4% and 84.2%, respectively. The best pair for ADC quantification was 50, 1000 s mm(-2) with 38/49 true-negative and 69/89 true-positive cases respectively; mean ADCs were 1.86 ± 0.46, 1.77 ± 0.37 and 1.15 ± 0.46 × 10(-3) mm(2) s(-1) for normal, benign and malignant lesions. There were no significant differences in these ADC values when compared with ADCall (ADC calculated from the full set of b - values) [difference = 0.0075 × 10(-3) mm(2) s(-1); confidence interval 95%: (-0.0036; 0.0186); p = 0.18].The diagnostic performance in differentiating malignant and benign lesions was most accurate for the b-value pair 50, 1000 s mm(-2).The best b-value pair for lesion discrimination and characterization through ADC quantification was 50, 1000 s mm(-2).

Purpose The aim of this work was to perform a qualitative and quantitative comparison of the performance of two fat suppression techniques on breast diffusion-weighted imaging (DWI). Materials and methods Fifty-one women underwent clinical breast magnetic resonance imaging, including DWI with short TI inversion recovery (STIR) and spectral attenuated inversion recovery (SPAIR). Four were excluded from the analysis due to image artefacts. Rating of fat suppression uniformity and lesion visibility were performed. Agreement between the two sequences was evaluated. Additionally, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and apparent diffusion coefficient (ADC) values for normal gland, benign and malignant lesions were compared. Receiver operating characteristic analysis was also performed. Results From the 52 lesions found, 47 were detected by both sequences. DWI-STIR evidenced more homogeneous fat suppression (p = 0.03). Although these lesions were seen with both techniques, DWI-SPAIR evidenced higher score for lesion visibility in nine of them. SNR and CNR were comparable, except for SNR in benign lesions (p < 0.01), which was higher for DWI-SPAIR. Mean ADC values for lesions were similar. ADC for normal fibroglandular tissue was higher when using DWI-STIR (p = 0.006). Sensitivity, specificity, accuracy and area under the curve values were alike: 84.0 % for both; 77.3, 71.4 %; 80.9, 78.3 %; 82.5, 81.3 % for DWI-SPAIR and DWI-STIR, respectively. Conclusion DWI-STIR showed superior fat suppression homogeneity. No differences were found for SNR and CNR, except for SNR in benign lesions. ADCs for lesions were comparable. Findings in this study are consistent with previous studies at 1.5 T, meaning that both fat suppression techniques are appropriate for breast DWI at 3.0 T.

This article reviews the current role of magnetic resonance imaging in the study of the pelvic floor anatomy and pelvic floor dysfunction. The application of static and dynamic magnetic resonance imaging in the clinical context and for biomechanical simulation modeling is assessed, and the main findings are summarized. Additionally, magnetic resonance–based diffusion tensor imaging is presented as a potential tool to evaluate muscle fiber morphology. In this article, focus is set on pelvic floor muscle damage related to urinary incontinence and pelvic organ prolapse, sometimes as a consequence of vaginal delivery. Modeling applications that evaluate anatomical and physiological properties of pelvic floor are presented to further illustrate their particular characteristics. Finally, finite element method is described as a method for modeling and analyzing pelvic floor structures’ biomechanical performance, based on material and behavioral properties of the tissues, and considering pressure loads that mimic real-life conditions such as active contraction or Valsalva maneuver.

To present an alternative measure (moment of inertia) to describe the anatomical features of the pelvic organ prolapse.A total of 30 women (21 diagnosed as having pelvic organ prolapse and 9 as controls) were evaluated by clinical scales and magnetic resonance imaging. Imaging biometric measures were carried out. Moment of inertia, pubovisceral muscle thickness and area, and levator hiatus anterior-to-posterior and lateral measures were compared by means of non-parametric tests, as well as their correlation with demographic features of the two sample groups.Moment of inertia, muscle area and levator hiatus diameters were statistically different between patients and controls. Furthermore, they were also well correlated with prolapse-associated factors, such as the number of vaginal deliveries and age, as well as Pelvic Organ Prolapse Quantification system and imaging staging of levator ani defects.Moment of inertia can be used as a new parameter to evaluate pelvic floor damage resulting from prolapse.

The ventromedial prefrontal cortex (vmPFC) is believed to be important in everyday preference judgments, processing emotions during decision-making. However, there is still controversy in the literature regarding the participation of the vmPFC. To further elucidate the contribution of the vmPFC in brand preference, we designed a functional magnetic resonance imaging (fMRI) study where 18 subjects assessed positive, indifferent, and fictitious brands. Also, both the period during and after the decision process were analyzed, hoping to unravel temporally the role of the vmPFC, using modeled and model-free fMRI analysis. Considering together the period before and after decision-making, there was activation of the vmPFC when comparing positive with indifferent or fictitious brands. However, when the decision-making period was separated from the moment after the response, and especially for positive brands, the vmPFC was more active after the choice than during the decision process itself, challenging some of the existing literature. The results of the present study support the notion that the vmPFC may be unimportant in the decision stage of brand preference, questioning theories that postulate that the vmPFC is in the origin of such a choice. Further studies are needed to investigate in detail why the vmPFC seems to be involved in brand preference only after the decision process.

The combination of electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) is a powerful tool to study brain function. In this study, we present a video-EEG-fMRI system where in-bore video, EEG and fMRI are acquired synchronously. To determine the added value of video in a typical EEG-fMRI scenario, we analyzed a simple motor activation paradigm (right index tapping). By using in-bore video, our results show that it is possible to determine different EEG potentials related to motion as well as to clearly distinguish the corresponding blood oxygen level dependent activations.

Pelvic organ prolapse (POP) is becoming a major health concern for women of all ages [Bump, 1998]. In particular, POP affect almost half of all women older than 50 years and 11.1% of these women will require surgery by the age of 80 [Subak, 2001]. Although pregnancy and vaginal delivery are considered the major causes for POP development, these factors do not totally explain the origin and progression of pelvic floor dysfunction in all women [Fornell, 2004]. The exercises of voluntary contraction of the pelvic floor are the mainstay of treatment of physical therapy for the Pelvic Floor Disorders. The aim of this study was analyse the displacement of pelvic floor muscles using the finite element method in women with POP and in a healthy women. This represents an attempt to better understand the PFM function and predict the results of pelvic floor muscle training in POP patients.

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