Resonance Imaging Of Skeletal Muscles Research Articles

Анализ данных магниторезонансной визуализации скелетных мышц и двигательных возможностей у пациентов с мышечной дистрофией Дюшенна

Анализ данных магниторезонансной визуализации скелетных мышц и двигательных возможностей у пациентов с мышечной дистрофией Дюшенна

SAT0302 Does MRI Have an Added Value over CK in Assessing Disease Activity in the Idiopathic Inflammatory Myopathies?

BackgroundMRI is the most widely used imaging procedure to assess disease activity of the idiopathic inflammatory Myopathies (IIM). Thigh muscle oedema, detected by T2-weighted and fat-suppressed (short tau inversion recovery,...

Diagnosis, pathogenesis and treatment of myositis: recent advances

Dermatomyositis (DM), polymyositis (PM), necrotizing myopathy (NM) and inclusion body myositis (IBM) are four distinct subtypes of idiopathic inflammatory myopathies - in short myositis. Recent studies have shed some light on the unique pathogenesis of each entity. Some of the clinical features are distinct, but muscle biopsy is indispensable for making a reliable diagnosis. The use of magnetic resonance imaging of skeletal muscles and detection of myositis-specific autoantibodies have become useful additions to our diagnostic repertoire. Only few controlled trials are available to substantiate current treatment approaches for myositis and hopes are high that novel modalities will become available within the next few years. In this review we provide an up-to-date overview of the pathogenesis and diagnostic approach of myositis. We aim to present a guide towards therapeutic and general management.

Magnetic resonance imaging of skeletal muscles in sporadic inclusion body myositis

To analyse whether MRI of upper and lower extremity muscles in a large patient group with sporadic IBM (sIBM) is of additional value in the diagnostic work-up of sIBM. Thirty-two sIBM patients were included. Magnetic resonance (MR) parameters evaluated in 68 muscles of upper and lower extremity were muscle atrophy, fatty infiltration and inflammation. These findings were correlated with disease duration, weakness and serum creatine kinase (sCK) levels. Fatty infiltration was far more common than inflammation. Muscles most frequently infiltrated with fat were the flexor digitorum profundus (FDP), anterior muscles of the upper leg and all muscles of the lower leg, preferentially the medial part of the gastrocnemius. The rectus femoris was relatively spared compared with other quadriceps muscles as well as the adductors of the upper leg. Inflammation was common in general, but individually sparse, present in 78% of the patients with a median of two inflamed muscles per patient. A statistically significant correlation was found between the amount of fatty infiltration and disease severity, disease duration and sCK. We provide a detailed description of the MRI in sIBM and show a distinct pattern of muscle involvement. Relatively severe affliction of the medial compartment of the gastrocnemius, combined with relative sparing of the rectus femoris or involvement of the FDP can be indicative of sIBM. MRI can contribute to the diagnosis in selected patients with clear clinical suspicion, but lacking the mandatory set of muscle biopsy features.

Magnetic resonance imaging of skeletal muscle

Clinical investigations of neuromuscular diseases routinely involve genetic, neurophysiological, biochemical and histopathological methods. More recently, various magnetic resonance imaging techniques have become available and extended the differential diagnostic possibilities. Using magnetic resonance imaging it is now possible to quantify muscle volume in selected body regions and measure wasting and exercise-induced muscle hypertrophy. Evidence is forthcoming that many hereditary myopathies are characterized by distinct patterns of muscle degeneration and this helps in selecting other relevant genetic and biochemical investigations. With diffusion-weighted tensor imaging it is possible to identify the microstructure of normal and diseased muscles. Arterial spin labelling is an emerging non-invasive tool to assess blood-flow changes in individual muscles. Magnetic resonance spectroscopy now provides an exciting opportunity to visualize metabolic changes and the pathophysiologically relevant cellular perturbations in muscle channelopathies affecting the muscle-specific sodium-channel isoform Na(v)1.4. Magnetic resonance imaging supplements investigations for the differential diagnosis of neuromuscular diseases. An advantage over routine neurophysiological or histopathological methods is that they are operator-independent, non-invasive and painless. Magnetic resonance imaging also has the advantage of providing a lasting detailed topographical picture of regional variations and allows robust measurements of muscle volume and various functional parameters.

Magnetic resonance imaging of skeletal muscles reveals a distinct pattern of muscle involvement in a family with congenital myopathy caused by a RYR1 mutation

Introduction: Mutations in the ryanodine receptor 1 gene (RYR1, MIM*180901) are associated with a wide range of phenotypes comprising central core disease (CCD), CCD with nemaline rods, clinically distinct subgroups of Multiminicore disease (MmD) and malignant hyperthermia (MHS) susceptibility trait. We report on the phenotype of a family with a congenital core and rod myopathy and a novel mutation in the RYR1 gene. Skeletal muscle magnetic resonance imaging (M-MRI) revealed a distinct pattern of muscle involvement. Case report: The eldest daughter (P1) had connatal hip dysplasia and delayed psychomotor development. At the age of 15 years P1 exhibits a moderate proximal muscle weakness with limited walking distance, myalgia on exertion and mild thoracolumbar scoliosis. P2 is the second daughter. She has a less severe phenotype with normal motor development, mild proximal muscle and facial weakness as well as bilateral feet deformities. Their mother (P3) is asymptomatic at the age of 45 years.

BOLD Magnetic Resonance Imaging of Skeletal Muscle

Blood-oxygen-level-dependent (BOLD) imaging was a concept introduced in 1990 for evaluating brain activation. The method relies on magnetic resonance imaging (MRI) contrast resulting from changes in the microvascular ratio of oxyhaemoglobin (oxyHb) to deoxyhaemoglobin (deoxyHb). OxyHb is diamagnetic, whereas deoxyHb is paramagnetic, which produces a local bulk magnetic susceptibility effect and subsequent MRI signal change. The changes are typically observed in T(2)*-weighted functional MRI scans. However, there has recently been interest in BOLD as a way to evaluate microcirculation of any normal or diseased tissue. This review focuses on the application of BOLD imaging in the understanding of normal and diseased skeletal muscle. In addition we present new findings showing the possible application of BOLD imaging with hyperoxia for evaluating skeletal muscle physiology.

Magnetic resonance imaging of skeletal muscles in the polymyositis

Magnetic resonance imaging of skeletal muscles was performed in 11 patients with polymyositis. Two types of muscle lesions were revealed. The first, inflammation, showed increased signal intensity on T2-weighted images and iso-intensity on T1-weighted images. The second, fatty replacement, showed increased signal intensity on both images. The coronal sections could elucidate the extension of the lesion in each affected muscle. Inflammation was relatively diffuse, while homogeneous fatty replacement tended to begin at the lower myotendinous junctions. © 1997 John Wiley & Sons, Inc. Muscle Nerve 20: 1463–1466, 1997

Magnetic resonance imaging of skeletal muscles in the polymyositis

Magnetic resonance imaging of skeletal muscles was performed in 11 patients with polymyositis. Two types of muscle lesions were revealed. The first, inflammation, showed increased signal intensity on T2-weighted images and iso-intensity on T1-weighted images. The second, fatty replacement, showed increased signal intensity on both images. The coronal sections could elucidate the extension of the lesion in each affected muscle. Inflammation was relatively diffuse, while homogeneous fatty replacement tended to begin at the lower myotendinous junctions.

Imaging techniques in myotonic dystrophy. A comparative study of ultrasound, computed tomography and magnetic resonance imaging of skeletal muscles

Limb and trunk muscles of 57 patients with the juvenile or adult form of myotonic dystrophy were studied by imaging techniques (ultrasound, computed tomography, magnetic resonance imaging). Typical findings were atrophy of the tibialis anterior and triceps brachii muscles and fatty degeneration of the vastus intermedius, sartorius, tibialis anterior and soleus muscles as well as of medial head of the gastrocnemius muscle. Magnetic resonance imaging was the most sensitive technique in depicting mesenchymal muscle alterations, followed by computed tomography and ultrasound. The data support that imaging is more sensitive in detecting the myophathy than measurement of the creatine kinase activity.

Magnetic Resonance Imaging of Skeletal Muscle in Patients with Duchenne Muscular Dystrophy

Magnetic Resonance Imaging of Skeletal Muscle in Patients with Duchenne Muscular Dystrophy

Magnetic resonance imaging of skeletal muscle. Prolongation of T1 and T2 subsequent to denervation.

The changes seen in the T1 and T2 relaxation times, water content and size of the extracellular fluid spaces of rat muscle samples following 15 days of denervation were studied by in vitro proton NMR spectrometry (10 MHz). Two different skeletal muscle groups (gastrocnemius and soleus) were studied. Denervation led to longer T1 values: 548 +/- 61 msec vs. 486 +/- 16 msec (P less than .05) for the gastrocnemius and 581 +/- 27 msec vs. 521 +/- 25 msec (P less than .05) for the soleus. Similar increases in T2 were measured. The sizes of the extracellular fluid spaces of denervated muscle were significantly larger despite a minor increase in total water content. Overall, the relaxation times of skeletal muscle correlated better with the size of the extracellular fluid space than with the total water content.