Stiffness Values Research Articles

Liver Stiffness Values to Predict Occurrence and Recurrence of Hepatocellular Carcinoma.

Globally, liver cancer is the third most frequent etiology of cancer death, with the rates of occurrence of both new cases and mortality estimated to increase. Given the availability of multiple treatments, interdisciplinary management of the patient is crucial. Moreover, the diagnostic assessment of patients with severe liver fibrosis is essential for the staging of HCC and liver cirrhosis and early diagnosis of HCC. In this context, non-invasive evaluation plays a critical role in identifying prognostic factors of clinical application for the surveillance of the occurrence or recurrence of HCC. The new frontiers of transient elastography have become a useful tool to assess the risk of HCC occurrence and recurrence. There has been a major increase in studies investigating the cutoff liver stiffness value that best predicts the need for monitoring for the onset of HCC. Therefore, this review discusses the new advances that have occurred in the last four years on HCC, highlighting the new frontiers of non-invasive evaluation of HCC subjects, with particular attention regarding the clinical application of liver stiffness assessment for de novo HCC and predicting recurrence in patients with chronic HCV achieving sustained virological response after treatment with direct antiviral agents.

Effect of Particle Size and Molarity of Hardening Solution on the Mechanical Properties of New Geopolymeric Mortars Manufactured from Mine Tailings

In this work, the effect of the maximum particle size and the molar concentration of the alkaline hardening solution on the mechanical response in uniaxial compression of geopolymeric mortars manufactured from the geopolymerization of Peruvian mine tailings dust was evaluated. The mechanical results found showed that the average mechanical resistance increased as the molar concentration of the hardening solution increased from 10 to 15M, on the other hand, it was possible to verify that as the particle size of sand and mine tailings is greater, the mechanical resistance values increased. The mechanical data found are in good agreement with the porosity results, that is, as the porosity values increased, the mechanical resistance gradually decreased. The stiffness values reported in the studied geopolymeric mortars showed a slight increase when the values of molar concentration and maximum particle size increased. All the mortars studied presented a similar microstructure, with fine sand particles dispersed within a continuous phase of geopolymer (geopolymerized mining tailings).

Comparison of testicular stiffness values obtained by ultrasound shear-wave elastography and magnetic resonance elastography in normal healthy volunteers

Objectives: This study aimed to contribute to the standardization of elastography by comparing stiffness values obtained from ultrasound shear wave elastography (SWE) and magnetic resonance elastography (MRE) of the testicular parenchyma in healthy volunteers. Methods: A total of 22 healthy volunteers (44 testes) were included in this study. Of the 26 cases analyzed, four were excluded from the study due to the exclusion criteria. The testicular parenchyma of the included patients was evaluated using MRE and SWE examinations. Pearson's correlation test was used to calculate the correlation between age and stiffness values, testicular volumes and stiffness values, and stiffness values from both examinations. Results: The mean SWE stiffness of the right testes was 5.560±3.1 kPa and the mean SWE stiffness of the left testes was 5.361±2.9 kPa. The mean MRE stiffness of the right testes was 6960.11±460 Pa and the mean MRE stiffness of the left testes was 6560.19±310 Pa. There was no significant correlation between SWE and MRE stiffness values (P=0.096). There was also no significant statistical correlation between SWE and MRE stiffness values and testicular volumes (P=0.17 and P=0.093, respectively). Conclusions: No statistical correlation was found between the stiffness values obtained by SWE and those obtained by MRE in the normal testicular parenchyma. Additionally, no conclusive relationship between stiffness levels, age, or testicular volume was discovered.

Comparing the Performance of Two Butcher-Based Block Hybrid Algorithms for the Solution of Initial Value Problems

In this paper, we compare the performances of two Butcher-based block hybrid methods for the numerical integration of initial value problems. We compare the condition numbers of the linear system of equations arising from both methods and the absolute errors of the solution obtained. The results of the numerical experiments illustrate that the better conditioned method outperformed its less conditioned counterpart based on the absolute errors. In addition, after applying our method on some examples, it was discovered that the absolute errors in this work were better than those of a recent study in the literature. Hence, we recommend this method for the numerical solution of stiff and non-stiff initial value problems.

Point Shear Wave Elastography Detected Liver Stiffness Increased in Pediatric Patient With Thalassemia Major.

Transient elastography (TE) and point shear wave elastography (pSWE) are 2 elastographic ultrasound examinations used in liver stiffness (LS) measurement. It was shown that the LS value detected by TE in pediatric β-thalassemia major patients has increased, and there was no LS evaluation obtained with pSWE in literature. Thus, in this study, it was aimed to evaluate LS with pSWE examination in children with thalassemia major and to determine LS-related parameters in these patients. Sixty-three schoolchildren with a diagnosis of β-thalassemia major and 21 healthy controls between the ages of 7 and 18 years were included. In addition to routine anamnesis, physical examination, and laboratory examinations, renal and liver ultrasounds were performed. Liver stiffness values were measured by pSWE examination. Serum levels of urea, aspartate-aminotransferase, alanine-aminotransferase, iron, and ferritin were significantly higher in patients, and serum creatinine, iron binding capacity, and hemoglobin levels were found to be significantly lower (P < 0.05 for each). Liver stiffness values were significantly higher in patients compared with healthy controls. In linear regression analysis, serum iron and iron binding capacity values were found to be closely related with LS (P < 0.001 vs. β = 0.482 and P = 0.047 vs. β = 0.237, respectively). Liver stiffness values obtained by pSWE examination increase significantly in patients. According to the results of our study, in addition to the previously known TE method, we think that the LS evaluation obtained by pSWE, a new method that can make more accurate measurements, can be used in the possible early detection of target organ damage in children with thalassemia major.

Variability of intervertebral joint stiffness between specimens and spine levels.

Introduction: Musculoskeletal multibody models of the spine can be used to investigate the biomechanical behaviour of the spine. In this context, a correct characterisation of the passive mechanical properties of the intervertebral joint is crucial. The intervertebral joint stiffness, in particular, is typically derived from the literature, and the differences between individuals and spine levels are often disregarded. Methods: This study tested if an optimisation method of personalising the intervertebral joint stiffnesses was able to capture expected stiffness variation between specimens and between spine levels and if the variation between spine levels could be accurately captured using a generic scaling ratio. Multibody models of six T12 to sacrum spine specimens were created from computed tomography data. For each specimen, two models were created: one with uniform stiffnesses across spine levels, and one accounting for level dependency. Three loading conditions were simulated. The initial stiffness values were optimised to minimize the kinematic error. Results: There was a range of optimised stiffnesses across the specimens and the models with level dependent stiffnesses were less accurate than the models without. Using an optimised stiffness substantially reduced prediction errors. Discussion: The optimisation captured the expected variation between specimens, and the prediction errors demonstrated the importance of accounting for level dependency. The inaccuracy of the predicted kinematics for the level-dependent models indicated that a generic scaling ratio is not a suitable method to account for the level dependency. The variation in the optimised stiffnesses for the different loading conditions indicates personalised stiffnesses should also be considered load-specific.

New bell plate controlled multi-inertia channel magnetorheological fluid mount wide frequency vibration isolation control study

This paper introduces a novel type of magnetorheological fluid (MRF) mount designed to achieve wide-frequency vibration isolation for engines. While previous studies have explored vibration isolation using hydraulic mounts, there has been limited research on achieving wideband isolation with MRF mounts. Consequently, this paper presents an innovative MRF mount structure and investigates wideband vibration isolation control for engines. Initially, experiments with a multi-channel MRF damper validate the switchable operation of controllable channels. A novel controllable multi-inertia channel MRF mount system is proposed, aligning the working mode of controllable inertia channels with that of the MRF damper. The lumped parameter method is employed to derive the mathematical model of the MRF mount, and its high and low-frequency dynamic characteristics are thoroughly examined. Subsequently, a real-time multi-island genetic algorithm-optimized controller is developed to investigate wideband vibration isolation within the MRF mount system. The findings indicate that: (1) The MRF mount demonstrates adjustable low-frequency dynamic stiffness and loss angle within the frequency range of f = 0–50 Hz. In the frequency range of f = 50–100 Hz, the mount achieves its lowest dynamic stiffness value, effectively addressing the issue of high-frequency stiffening. (2) The real-time multi-island genetic optimized controller exhibits superior vibration isolation performance compared to traditional sky-hook control and hybrid sky-hook control methods, achieving optimal vibration isolation for the mount.

Low-profile prosthetic foot stiffness category and size, and shoes affect axial and torsional stiffness and hysteresis.

Passive-elastic prosthetic feet are manufactured with numerical stiffness categories and prescribed based on the user's body mass and activity level, but mechanical properties, such as stiffness values and hysteresis are not typically reported. Since the mechanical properties of passive-elastic prosthetic feet and footwear can affect walking biomechanics of people with transtibial or transfemoral amputation, characterizing these properties can provide objective metrics for comparison and aid prosthetic foot prescription and design. We characterized axial and torsional stiffness values, and hysteresis of 33 categories and sizes of a commercially available passive-elastic prosthetic foot model [Össur low-profile (LP) Vari-flex] with and without a shoe. We assumed a greater numerical stiffness category would result in greater axial and torsional stiffness values but would not affect hysteresis. We hypothesized that a greater prosthetic foot length would not affect axial stiffness values or hysteresis but would result in greater torsional stiffness values. We also hypothesized that including a shoe would result in decreased axial and torsional stiffness values and greater hysteresis. Prosthetic stiffness was better described by curvilinear than linear equations such that stiffness values increased with greater loads. In general, a greater numerical stiffness category resulted in increased heel, midfoot, and forefoot axial stiffness values, increased plantarflexion and dorsiflexion torsional stiffness values, and decreased heel, midfoot, and forefoot hysteresis. Moreover, for a given category, a longer prosthetic foot size resulted in decreased heel, midfoot, and forefoot axial stiffness values, increased plantarflexion and dorsiflexion torsional stiffness values, and decreased heel and midfoot hysteresis. In addition, adding a shoe to the prosthetic foot resulted in decreased heel and midfoot axial stiffness values, decreased plantarflexion torsional stiffness values, and increased heel, midfoot, and forefoot hysteresis. Our results suggest that manufacturers should adjust the design of each category to ensure the mechanical properties are consistent across different sizes and highlight the need for prosthetists and researchers to consider the effects of shoes in combination with prostheses. Our results can be used to objectively compare the LP Vari-flex prosthetic foot to other prosthetic feet to inform their prescription, design, and use for people with a transtibial or transfemoral amputation.

Nonlinear Vibration and Stiffness Characteristics Analysis of Maglev Train Based on Cubic Displacement Control

A control strategy combining cubic displacement feedback nonlinear control and proportional-differential (PD) linear control is used to control the vibration performance of the maglev system. The maglev system is divided into positive stiffness maglev system, quasi-zero stiffness maglev system and negative stiffness maglev system according to the linear stiffness value of maglev system. Firstly, an improved multi-scale method is used to analyze the vibration characteristics of suspension in the positive stiffness state of the maglev system. Secondly, the influence of control parameters on train vibration amplitude and vibration center displacement under quasi-zero stiffness is studied. Finally, the vibration characteristics of the train when the maglev system is in negative stiffness are analyzed by numerical simulation. The maglev system exhibits the worst vibration performance under negative stiffness compared with positive stiffness and quasi-zero stiffness. The suspension frame is easy to enter the chaotic motion state, and its vibration center is easy to deviate from the equilibrium position and produce large displacement when the maglev system is in the negative stiffness state. The control results show that the control strategy combining the cubic displacement feedback nonlinear control with the PD linear control can make the maglev system exhibit better vibration characteristics under positive and quasi-zero stiffness.

THE EFFECT OF LEG STIFFNESS ON REACTIVE AGILITY, JUMPING AND SPEED IN GYMNASTICS ATHLETES

In reviewing the literature, it was decided to conduct this study due to the lack of studies investigating the influence of leg stiffness on performance parameters such as reactive agility, jumping power and speed in gymnasts. The aim of this study is to investigate the effects of gymnasts' leg stiffness on performance parameters such as reactive agility, jump and speed. For this purpose, 65 gymnastics athletes aged 12-22 years were included in the study. The drop jump test (with Optojump measuring device) was used to evaluate the jump, and the vertical jump test (Optojump measuring device) for the evaluation of leg stiffness, while the 20m sprint test (with Witty measuring device) was made for speed evaluation. The measurements of reactive agility were performed with the SpeedCourt™. As a result of our study, we found a moderate positive correlation between the leg stiffness values and the reactive strength index (RSI) values obtained from the gymnastics athletes' jump tests. In addition, we found a negative relationship at a low level between speed and agility with leg stiffness values. It can be concluded that increasing gymnasts' leg stiffness contributes positively to jumping power, speed and reactive agility. In this case, it is recommended to include plyometric exercises in the training programs to improve the leg stiffness of trampoline gymnasts, rhythmic gymnasts and artistic gymnasts who focus on jumping.

Exceptional Viscoelastic Properties in Graphene Oxide Films.

Materials that combine high stiffness with effective damping are in high demand across various industries. While polymers excel in damping, they often lack stiffness and thermal stability. Conversely, metals and ceramics boast high mechanical and thermal properties but lack damping. This study demonstrates that graphene oxide (GO) and reduced graphene oxide (rGO) films can achieve exceptional viscoelastic properties across a wide temperature range. Furthermore, it explains the damping mechanisms and structural characteristics that influence the unique viscoelastic behavior of GO and rGO films. Through comprehensive characterizations, this study correlates the structure and spatial variation in local strain (measured with in situ Raman microscopy) of GO and rGO films with their storage and loss moduli. This correlation links these properties to the water loss as a function of the temperature rise. GO and rGO films exhibited a damping coefficient of 0.2-0.4 while maintaining stiffness values of 10-20 GPa in the 30-120 °C range. These high damping values were attributed to intermittent slippage and hydrogen bond density between the constituent sheets. Numerical modeling was conducted to further elucidate the mechanisms responsible for the properties noted in these films. This study enhances our understanding of the viscoelastic properties of GO films and offers a new potential material for applications across various fields.

Scapular muscle dynamic stiffness of asymptomatic subjects and subjects with chronic shoulder pain, at rest and isometric contraction conditions.

Muscle stiffness had a crucial role in joint stability, particularly, at the shoulder complex. Although changes in upper trapezius muscle stiffness have been described for shoulder pain, contradictory findings have been obtained. Also, existing data regarding scapular muscles are, majorly, about trapezius. Myotonometry is a method used to assess stiffness; however, the reliability values of scapular muscle stiffness through this method have not been assessed in shoulder pain conditions. The present study aims to compare scapular muscles' stiffness (trapezius, serratus anterior, and levator scapulae) between subjects with and without chronic shoulder pain and to evaluate the related test-retest reliability. Twenty-two symptomatic and twenty-two asymptomatic subjects participated in a cross-sectional study. The dynamic muscular stiffness of scapular muscles, at rest and during an isometric contraction, was measured bilaterally with myotonometry, in two moments. The differences in bilateral averaged values between symptomatic and asymptomatic subjects and the effect of the group (group presenting pain in the dominant or non-dominant side, and asymptomatic group) and of the limb (unilateral painful or asymptomatic limb, and bilateral asymptomatic limbs) were investigated. Test-retest intra-rater reliability was determined. An effect of the group was observed at rest, for middle trapezius stiffness, and during contraction, for middle and lower trapezius stiffness. For middle trapezius, increased values were observed in the group presenting pain in non-dominant side comparing to both groups or to group presenting pain in dominant side. The intraclass correlation coefficient, majorly, ranged between 0.775 and 0.989. Participants with pain in the non-dominant side presented an increased middle trapezius' stiffness. Globally, high reliability was observed for scapular muscles dynamic stiffness.

Uncertainty in Distinct Element Modeling of Freestanding Structures Considering Stiffness Parameters

ABSTRACT Numerical studies on freestanding structures typically leverage the Distinct Element Method where the response is dictated by joints; however, the response carries significant uncertainty due to joint stiffness parameters. This study aims to quantify the influence of joint stiffness parameters on the global response of freestanding structures subjected to seismic excitation in a probabilistic formulation. By using a range of joint stiffness values with rectangular rigid blocks of different aspect ratios, the impact of joint stiffness parameters is evaluated against a large suite of historical ground motions. Results indicate that increasing contact stiffness results in increased stability against overturning.

A comparative analysis of the vibrational behavior of various beam models with different foundation designs

This article discusses the modal behavior of elastically constrained beams under various types of foundations and provides insights into the effects of different factors on the eigenfrequencies of beams. Numerical and analytical techniques, specifically the Galerkin finite element method (GFM) and the separation of variables, are utilized to determine the eigenfrequencies and mode shapes of beams. Modal analysis of Timoshenko, shear, Rayleigh, and Euler-Bernoulli beams that are elastically constrained and resting on Winkler, Pasternak, and Hetényi foundations, considering non-classical boundary conditions, is included in the study. The effects of factors such as flexural rigidity, transverse modulus, and Winkler foundation constant on natural frequencies of different beam models are investigated. The proposed method efficiently converges to the exact solution without shear locking in the stiffness element. The results demonstrate that the natural frequencies of the beam rise because of the shear layer, flexural rigidity, and foundation constant. Furthermore, the Hetényi elastic foundation affects the natural frequency of the beam, depending on the relative values of beam stiffness and foundation stiffness. Additionally, incorporating both shear deformation and rotary inertia has a greater impact on the eigenfrequencies of Euler-Bernoulli beams compared to incorporating only one of these effects. The findings of this work provide valuable insights into the behavior of beams under different foundation conditions and have potential applications in the design and optimization of structures incorporating beams, thereby enhancing the understanding of beam analysis.

A New Fixed Coefficient Diagonally Implicit Block Backward Differentiation Formula for Solving Stiff Initial Value Problems

Stiff initial value problems in ordinary differential equations occur when solution components evolve at varying rates, posing challenges for traditional computational methods. Specialized techniques are crucial for maintaining accuracy and stability during rapid transitions, emphasizing their significance in developing reliable numerical algorithms across scientific and engineering applications. This study aims to develop a new fixed coefficient 3-point diagonally implicit block backward differentiation formula for the numerical solution of first order stiff initial value problems. The method is constructed by integrating a triangular matrix into the coefficient matrix of an existing extended 3-point super class of block BDF for solving stiff initial value problems. The selection of a fixed coefficient within the interval accompanies this integration to ensure optimal stability. The method is found to order five. Stability analysis indicates that the method is consistent, zero-stable, and almost A-stable, validating its applicability to stiff initial value problems. Implementation of the method involves Newton’s iteration, and a code in the C programming language is devised to demonstrate its effectiveness. Comparative examination of numerical outcomes with the existing 3BBDF and 3ESBBDF methods highlights the proposed method's enhanced accuracy and reduced computation time.

Torsional vibration behavior of a restrained non-circular nanowire in an elastic matrix

This study introduces an approach to analyze torsional vibration in non-circular nanowires within magnetic fields, considering various boundary conditions on an elastic foundation. Analytical formulas for natural angular frequencies are obtained using nonlocal strain gradient theory. The analysis covers three non-circular cross-sections, incorporating the warping effect. Elastic springs at the wire ends simulate support conditions, restricting rotation around the wire’s axis. The torsion function around the axis is represented by a Fourier series, discretized at the spring points and linked using the Stokes’ transform alongside the boundary values. This leads to an eigenvalue problem that includes higher-order material size parameters (strain gradient, nonlocal), spring parameters, and the warping function. The study’s novelty lies in effectively solving torsional vibration for non-circular sections, addressing warping function, elastic medium, and size effects under both deformable and non-deformable boundary conditions. The presented solution is capable of determining vibration frequencies for both rigid and deformable boundary conditions. This is accomplished by specifying the torsional spring stiffness values, thereby obviating the necessity for additional recalculations. In order to verify the obtained results and compare them with the existing literature, nanowires with free and clamped boundary conditions are solved numerically by changing the spring parameters in the eigenvalue problem. In the formulation of natural angular frequency; length scale parameters, warping, magnetic field, elastic medium effects are included. In addition, since the support conditions are modeled with elastic springs, the resulting formulas are quite general and can be used to solve different types of torsional vibration problems.

Micromechanics of fibrous scaffolds and their stiffness sensing by cells

Mechanical properties of the tissue engineering scaffolds are known to play a crucial role in cell response. Therefore, an understanding of the cell-scaffold interactions is of high importance. Here, we have utilized discrete fiber network model to quantitatively study the micromechanics of fibrous scaffolds with different fiber arrangements and cross-linking densities. We observe that localized forces on the scaffold result in its anisotropic deformation even for isotropic fiber arrangements. We also see an exponential decay of the displacement field with distance from the location of applied force. This nature of the decay allows us to estimate the characteristic length for force transmission in fibrous scaffolds. Furthermore, we also looked at the stiffness sensing of fibrous scaffolds by individual cells and its dependence on the cellular sensing mechanism. For this, we considered two conditions- stress-controlled, and strain-controlled application of forces by a cell. With fixed strain, we find that the stiffness sensed by a cell is proportional to the scaffold’s ‘macroscopic’ elastic modulus. However, under fixed stress application by the cell, the stiffness sensed by the cell also depends on the cell’s own stiffness. In fact, the stiffness values for the same scaffold sensed by the stiff and soft cells can differ from each other by an order of magnitude. The insights from this work will help in designing tissue engineering scaffolds for applications where mechanical stimuli are a critical factor.

Simulation of optomechanical interaction of levitated nanoparticle with photonic crystal micro cavity.

We propose and analyze theoretically a promising design of an optical trap for vacuum levitation of nanoparticles based on a one-dimensional (1D) silicon photonic crystal cavity (PhC). The considered cavity has a quadratically modulated width of the silicon wave guiding structure, leading to a calculated cavity quality factor of 8 × 105. An effective mode volume of approximately 0.16 μm3 having the optical field strongly confined outside the silicon structure enables optical confinement on nanoparticle in all three dimensions. The optical forces and particle-cavity optomechanical coupling are comprehensively analyzed for two sizes of silica nanoparticles (100 nm and 150 nm in diameter) and various mode detunings. The value of trapping stiffnesses in the microcavity is predicted to be 5 order of magnitudes higher than that reached for optimized optical tweezers, moreover the linear single photon coupling rate can reach MHz level which is 6 order magnitude larger than previously reported values for common bulk cavities. The theoretical results support optimistic prospects towards a compact chip for optical levitation in vacuum and cooling of translational mechanical degrees of motion for the silica nanoparticle of a diameter of 100 nm.

Design of birch plywood as gusset plates in timber-timber uniaxial tension connections: Influence of fastener pattern, face grain orientation, and discussions based on the Whitmore effective width theory

This study reveals timber-timber composite joints consisting of glulam pieces and birch plywood plates with three different load-to-face grain angles. Utilizing a similar number of fasteners and arranging the fastener array from narrow to wide, uniaxial tension specimens were manufactured with four different fastener patterns. The thickness of birch plywood was intentionally under-designed so that the failure modes for all connections were net tension failure of birch plywood plates. Thereafter, the influence of the fastener pattern and face grain orientation on the load-bearing capacity and stiffness of the investigated composite joints was studied. The load capacity and nominal strength generally increased when the nail patterns varied from narrow to wide. This observation was associated with the Whitmore effective width theory (load spread angle) in steel gusset plate design. Moreover, to derive valid analytical methods to predict the net-tension capacity of birch plywood plates, the classic spread angle model that assumes rectangular stress blocks and the modified spread angle model that considers the summation of stresses from each fastener row were discussed. Both models were adopted to predict the net tension capacity of investigated specimens at 0°. In addition, the stiffness of joints was measured and compared with slip modulus formulas in Eurocode 5. The measured local stiffness values were found to be independent of the fastener pattern and load-face grain angles. The analytical slip modulus assuming the case without predrilling exhibited a satisfactory prediction, while formulas assuming the case with predrilling tend to give overestimations.

Liver Magnetic Resonance Elastography: Focus on Methodology, Technique, and Feasibility.

Magnetic resonance elastography (MRE) is an imaging technique that combines low-frequency mechanical vibrations with magnetic resonance imaging to create visual maps and quantify liver parenchyma stiffness. As in recent years, diffuse liver diseases have become highly prevalent worldwide and could lead to a chronic condition with different stages of fibrosis. There is a strong necessity for a non-invasive, highly accurate, and standardised quantitative assessment to evaluate and manage patients with different stages of fibrosis from diagnosis to follow-up, as the actual reference standard for the diagnosis and staging of liver fibrosis is biopsy, an invasive method with possible peri-procedural complications and sampling errors. MRE could quantitatively evaluate liver stiffness, as it is a rapid and repeatable method with high specificity and sensitivity. MRE is based on the propagation of mechanical shear waves through the liver tissue that are directly proportional to the organ's stiffness, expressed in kilopascals (kPa). To obtain a valid assessment of the real hepatic stiffness values, it is mandatory to obtain a high-quality examination. To understand the pearls and pitfalls of MRE, in this review, we describe our experience after one year of performing MRE from indications and patient preparation to acquisition, quality control, and image analysis.