Effects of Moderate and Heavy Slow Resistance Training on Achilles and Patellar Tendons and Muscles Aponeuroses in Elderly Men.

To investigate the effect of moderate or heavy slow resistance training on structural and mechanical properties of patellar and Achilles tendons in older men, in vivo. Healthy older men (n = 27) undertook a 12-week resistance training program (3 times/week) of triceps surae and quadriceps muscle-tendon complexes. Participants were randomly assigned to either a moderate load of 55% 1RM (O55, n = 13, age: 70.

Monitoring of lung stiffness for long-COVID patients using magnetic resonance elastography (MRE).

Purpose: Transaxial CT imaging is the main clinical imaging modality for the assessment of COVID-induced lung damage. However, this type of data does not quantify the functional properties of the lung. The objective is to provide non-invasive personalized cartographies of lung stiffness for long-COVID patients using MR elastography (MRE) and follow-up the evolution of this quantitative mapping over time.

Structure and function of Achilles and patellar tendons following moderate slow resistance training in young and old men.

The aim of this study was to investigate the effect of aging and resistance training with a moderate load on the size and mechanical properties of the patellar (PT) and Achilles tendon (AT) and their associated aponeuroses; medial gastrocnemius (MG) and vastus lateralis (VL). Young (Y55; 24.8 ± 3.

Improved Ultrasound Attenuation Measurement Method for the Non-invasive Evaluation of Hepatic Steatosis Using FibroScan.

Controlled attenuation parameter (CAP) is a measurement of ultrasound attenuation used to assess liver steatosis non-invasively. However, the standard method has some limitations. This study assessed the performance of a new CAP method by ex vivo and in vivo assessments.

Muscles adaptation to aging and training: architectural changes - a randomised trial.

Background: To investigate how anatomical cross-sectional area and volume of quadriceps and triceps surae muscles were affected by ageing, and by resistance training in older and younger men, in vivo.

Methods: The old participants were randomly assigned to moderate (O55, n = 13) or high-load (O80, n = 14) resistance training intervention (12 weeks; 3 times/week) corresponding to 55% or 80% of one repetition maximum, respectively. Young men (Y55, n = 11) were assigned to the moderate-intensity strengthening exercise program.

Development of a phantom mimicking the functional and structural behaviors of the thigh muscles characterized with magnetic resonance elastography technique.

Magnetic Resonance Elastography (MRE) is a non invasive technique based on the propagation of shear waves in soft tissues providing the quantification of the mechanical properties [1]. MRE was successfully applied to healthy and pathological muscles. However, the MRE muscle methods must be further improved to characterize the deep muscles.

Viscoelastic shear properties of in vivo thigh muscles measured by MR elastography.

Purpose: To measure the viscoelastic properties of passive thigh muscles using multifrequency magnetic resonance elastography (MMRE) and rheological models.

Materials And Methods: Four muscles in five volunteers underwent MMRE tests set up inside a 1.5T magnetic resonance imaging (MRI) scanner.

Quantifying the Elastic Property of Nine Thigh Muscles Using Magnetic Resonance Elastography.

Background: Pathologies of the muscles can manifest different physiological and functional changes. To adapt treatment, it is necessary to characterize the elastic property (shear modulus) of single muscles. Previous studies have used magnetic resonance elastography (MRE), a technique based on MRI technology, to analyze the mechanical behavior of healthy and pathological muscles.

Analysis of shear wave propagation derived from MR elastography in 3D thigh skeletal muscle using subject specific finite element model.

The purpose of this study was to develop a subject specific finite element model derived from MRI images to numerically analyze the MRE (magnetic resonance elastography) shear wave propagation within skeletal thigh muscles. A sagittal T2 CUBE MRI sequence was performed on the 20-cm thigh segment of a healthy male subject. Skin, adipose tissue, femoral bone and 11 muscles were manually segmented in order to have 3D smoothed solid and meshed models.

In vivo assessment of nervous fiber distribution in the intervertebral disc.

This present study aims to assess in vivo the nervous fibers distribution in the intervertebral disc using diffusion tensor imaging technique. Five healthy subjects participated into the data acquisition. Fiber extraction and tracking algorithms were used.

Identification process based on shear wave propagation within a phantom using finite element modelling and magnetic resonance elastography.

Magnetic resonance elastography (MRE), based on shear wave propagation generated by a specific driver, is a non-invasive exam performed in clinical practice to improve the liver diagnosis. The purpose was to develop a finite element (FE) identification method for the mechanical characterisation of phantom mimicking soft tissues investigated with MRE technique. Thus, a 3D FE phantom model, composed of the realistic MRE liver boundary conditions, was developed to simulate the shear wave propagation with the software ABAQUS.

A possible clinical tool to depict muscle elasticity mapping using magnetic resonance elastography.

Introduction: Characterization of muscle elasticity will improve the diagnosis and treatment of muscle disorders. The purpose is to compare the use of magnetic resonance elastography (MRE) and ultrasound elastography (USE) techniques to elucidate the MRE cartography of thigh muscles.

Methods: Both elastography techniques were performed on 5 children and 7 adults.

Analysis of liver viscosity behavior as a function of multifrequency magnetic resonance elastography (MMRE) postprocessing.

Purpose: To analyze the relevance of the viscosity measurement as a liver diagnostic marker.

Materials And Methods: To determine the level of fibrosis, a Fibroscan test was performed on 40 subjects (10 healthy volunteers and 30 patients). Subsequently, multifrequency magnetic resonance elastography (MMRE) tests were made with a pneumatic driver at 60, 70, and 80 Hz.

Cutoff values for alcoholic liver fibrosis using magnetic resonance elastography technique.

Background: Due to the lack of cutoff values validated for specific liver diseases, the purpose of this study was to set up specific magnetic resonance elastography (MRE) cutoff values for asymptomatic liver fibrosis in alcoholic patients.

Methods: Ninety patients underwent 3 clinical exams. The liver stiffness was measured locally with the Fibroscan, and globally through cartographies of shear modulus generated with MRE.

Characterization of a hyper-viscoelastic phantom mimicking biological soft tissue using an abdominal pneumatic driver with magnetic resonance elastography (MRE).

The purpose of this study was to create a polymer phantom mimicking the mechanical properties of soft tissues using experimental tests and rheological models. Multifrequency Magnetic Resonance Elastography (MMRE) tests were performed on the present phantom with a pneumatic driver to characterize the viscoelastic (μ, η) properties using Voigt, Maxwell, Zener and Springpot models. To optimize the MMRE protocol, the driver behavior was analyzed with a vibrometer.

Stiffness imaging of the kidney and adjacent abdominal tissues measured simultaneously using magnetic resonance elastography.

To date, non-invasive methods to detect kidney malignancies and mild tumors remain a challenge. The purpose of this study was to establish the proper imaging protocol to determine kidney stiffness and its spatial distribution within the various kidney compartments such as the renal sinus, medulla, and cortex. Here, we have used magnetic resonance elastography (MRE) along with coronal oblique acquisition to simultaneously measure kidney stiffness in comparison with other tissues including the liver, spleen, and psoas.

Analysis of thigh muscle stiffness from childhood to adulthood using magnetic resonance elastography (MRE) technique.

Background: Magnetic resonance elastography has been performed in healthy and pathological muscles in order to provide clinicians with quantitative muscle stiffness data. However, there is a lack of data on pediatric muscle. Therefore, the present work studies age-related changes of the mechanical properties.

Characterization of muscle architecture in children and adults using magnetic resonance elastography and ultrasound techniques.

The purpose of this study is to characterize the muscle architecture of children and adults using magnetic resonance elastography and ultrasound techniques. Five children (8-12 yr) and seven adults (24-58 yr) underwent both tests on the vastus medialis muscle at relaxed and contracted (10% and 20% of MVC) states. Longitudinal ultrasonic images were performed in the same area as the phase image showing the shear wave's propagation.

Measurement of liver stiffness with two imaging techniques: magnetic resonance elastography and ultrasound elastometry.

Purpose: To cross-validate the magnetic resonance elastography (MRE) technique with a clinical device, based on an ultrasound elastometry system called Fibroscan.

Materials And Methods: Ten healthy subjects underwent an MRE and a Fibroscan test. The MRE technique used a round pneumatic driver at 60 Hz to generate shear waves inside the liver.