Imaging respiratory muscle quality and function in Duchenne muscular dystrophy
The objective of this study was to assess respiratory muscle quality and function in DMD using magnetic resonance imaging and to determine the relationship to clinical respiratory function.MethodsIndividuals with DMD (n = 36) and unaffected controls (n = 12) participated in this cross sectional magnetic resonance imaging study. Participants underwent dynamic imaging of the thorax to assess diaphragm and chest wall mobility and chemical shift-encoded imaging of the chest and abdomen to determine fatty infiltration of the accessory respiratory muscles. Additionally, clinical pulmonary function measures were obtained.ResultsThoracic cavity area was decreased in individuals with DMD compared to controls during tidal and maximal breathing. Individuals with DMD had reduced chest wall movement in the anterior –posterior direction during maximal inspirations and expirations, but diaphragm descent during maximal inspirations (normalized to height) was only decreased in a subset of individuals with maximal inspiratory pressures less than 60% predicted. Muscle fat fraction was elevated in all three expirat ory muscles assessed (p
Neuropediatrics DOI: 10.1055/s-0039-1695787Muscular dystrophy-dystroglycanopathies (MDDG) are a group of genetically heterogeneous autosomal recessive disorders characterized by hypoglycosylation of α-dystroglycan. Here, we report on two female patients from a consanguineous Lebanese family that presented in early infancy with generalized muscle hypotonia and primary microcephaly. Brain magnetic resonance imaging (MRI) showed different degrees of hypoplasia of the cerebellar vermis and hypoplasia of corpus callosum. Muscle biopsy analyses revealed a muscular dystrophy with reduced expression of α-dystroglycan a...
Duchenne muscular dystrophy (DMD) results in progressive loss of functional capacities, which is a reflection of loss of muscle mass with contractile tissue being replaced by fat tissue. Currently, measurements of lean body mass (LBM) in DMD include dual energy x-ray absorptiometry (DEXA) and magnetic resonance imaging (MRI). Studies have shown that a decrease in LBM correlates with decreased quantitative strength measurements. However, DXA and MRI require cooperation from the subject and scanning can be uncomfortable for subjects in a more advanced stage of the disease with severe contractures or spine deformities.
There is currently no cure for the fatal X-linked disorder Duchenne muscular dystrophy (DMD) and clinically-applicable translational trials continue to rely heavily on use of animal models. The Royal Veterinary College has a unique colony of dystrophin deficient dogs: the deltaE50-MD dog model. Magnetic Resonance Imaging (MRI) is a valuable non-invasive technique for monitoring the progression of the disease in human DMD patients. The aim was to determine if the deltaE50-MD dog has a skeletal muscle MRI phenotype that resembles that of DMD boys and to determine MRI differences of skeletal muscles in dystrophic and wildtype dogs.
Reliable outcome measures able to demonstrate specific trends of disease progression are essential in this era of clinical trials in DMD. Magnetic resonance imaging (MRI) is increasingly being used to assess muscular degeneration in dystrophic patients. We studied muscle diaphragm through MRI and correlated MRI measurements of diaphragm structure and function with compartmental tidal volumes measured by opto-electronic plethysmography (OEP) and pulmonary function tests. 26 DMD patients and 12 age-matched controls were acquired in breath-hold on a 3T-scanner at full-expiration (EXP) and full-inspiration (INSP), by a multi-p...
Several studies in Duchenne muscular dystrophy (DMD) have shown trajectories of mostly functional outcome measures across several years. Additionally, longitudinal quantitative nuclear magnetic resonance imaging (qNMRI) data have been subject of a series of studies in recent years. Here, we present longitudinal qNMRI data in forearm for up to seven years in the AFM Genethon-sponsored DMD natural history study. We wanted to investigate how well disease progression could be predicted using a sigmoidal model.
Duchenne muscular dystrophy (DMD) is an X-linked muscle-wasting condition caused by a lack of the protein dystrophin. Approximately 50% of patients also have central nervous system co-morbidities, such as intellectual disability (ID), autism, emotional and behavioural problems. The risk of ID, and possibly other disorders, increases when shorter forms of dystrophin transcribed in the CNS are also absent (Dp140/Dp71 isoforms). Previous brain magnetic resonance imaging (MRI) studies in DMD have shown smaller total brain and grey matter volume and altered corpus callosal white matter microstructure.
Carriers of Duchenne and Becker muscular dystrophy (DMD/BMD) have recently been demonstrated to have discrete fibrosis by cardiac magnetic resonance imaging (CMR) with late gadolinium enhancement (LGE). Risk factors for demonstration of cardiomyopathy by CMR have not been described and more diffuse fibrosis by T1 imaging has not been reported in carriers. We performed a case-control study in 76 genetically-confirmed muscular dystrophy carriers (MDC), 22 non-carrier moms of DMD/BMD boys, and 25 age-matched controls.
ConclusionsWe conclude that skeletal muscle MRI represents a useful tool in the diagnostic workup and clinical management of LGMDR1.
Muscular dystrophy is a group of genetically inherited diseases with irreversible and progressive muscle loss and is associated with cardiac involvement. Particularly in Duchenne and Becker dystrophies, cardiac disorders are the leading causes of mortality. Cardiovascular magnetic resonance imaging (CMR) can detect even incipient myocardial fibrosis (late gadolinium enhancement), which has prognostic significance in patients with preserved left ventricular function by echocardiogram and before the onset of symptoms. Early detection of cardiac abnormalities by CMR enables early cardioprotective treatment, leading to a better prognosis.
CONCLUSION: To assess function of the upper extremities the Brooke upper extremity functional rating scale or the performance of upper limb test should be used. For assessment of pulmonary function measurement of forced vital capacity (FVC) is recommended. The extent of cardiac involvement can best be evaluated using cardiac magnetic resonance imaging (MRI), measurement of the ejection fraction (EF) and the left ventricular shortening fraction (LVSF) by echocardiography. The pediatric quality of life inventory should be used for assessment of quality of life. In addition, the body mass index (BMI), the number of infections...