Musculoskeletal imaging; MRI; Electrical Muscle Stimulation; MR Spectroscopy
Deligianni Xeni, Klenk Christopher, Place Nicolas, Garcia Meritxell, Pansini Michele, Hirschmann Anna, Schmidt-Trucksäss Arno, Bieri Oliver, Santini Francesco (2019), Dynamic MR imaging of the skeletal muscle in young and senior volunteers during synchronized minimal neuromuscular electrical stimulation, in Magnetic Resonance Materials in Physics, Biology and Medicine
Strijkers Gustav J., Araujo Ericky C.A., Azzabou Noura, Bendahan David, Blamire Andrew, Burakiewicz Jedrek, Carlier Pierre G., Damon Bruce, Deligianni Xeni, Froeling Martijn, Heerschap Arend, Hollingsworth Kieren G., Hooijmans Melissa T., Karampinos Dimitrios C., Loudos George, Madelin Guillaume, Marty Benjamin, Nagel Armin M., Nederveen Aart J., Nelissen Jules L., Santini Francesco, Scheidegger Olivier, Schick Fritz, Sinclair Christopher, et al. (2019), Exploration of New Contrasts, Targets, and MR Imaging and Spectroscopy Techniques for Neuromuscular Disease – A Workshop Report of Working Group 3 of the Biomedicine and Molecular Biosciences COST Action BM1304 MYO-MRI, in Journal of Neuromuscular Diseases
, 6(1), 1-30.
Santini Francesco, Bieri Oliver, Deligianni Xeni (2018), OpenForce MR: A low-cost open-source MR-compatible force sensor, in Concepts in Magnetic Resonance Part B: Magnetic Resonance Engineering
, 48B(4), e21404-e21404.
Assessing the functionality of skeletal muscle fibers is essential in the progress monitoring of both pathological (neuro- and musculodegenerative) and physiological processes (training and rehabilitation). While morphological information is mostly important in the longitudinal follow-up of a single patient, it is not an absolute marker of organ health. In order to obtain an absolute indication of muscle status, it is necessary to follow a functional approach, which would monitor the ability of the muscle to contract and to gather supplies of nutrients and oxygen from the blood. This approach can follow two paths: the first is the studying of the muscular kinematics using gated or real-time sequences during muscle movement; the second is metabolic assessment, which can either be measured directly (through 31P spectroscopy of muscle metabolites) or indirectly (for example by T2- or T2*-weighted imaging).In the last two years, our group has been developing a novel approach to acquire high-temporal-resolution images of the contraction of the skeletal muscle by inducing a reproducible movement by means of electrical muscle stimulation (EMS). With this method, contraction speed, strain, and strain rate were measured in a consistent and controlled way.This approach revealed itself promising for the purpose of observing the functionality of the muscles. However, so far it has been only developed for the study of kinematics, thus missing the metabolic information, and while further studies are ongoing, a clinical validation of the method is still needed. In addition, quantitative evaluation of the safety of the hardware setup connected to the subject has so far limited the acquisition to low-power sequences.Ideally, one would extend this approach to a more general “toolbox” consisting of methods that can give a broader view on the muscle functionality, coupling contractility and metabolism in the same kind of setup.In the first part of this project, we propose to continue the development of the synchronized imaging method, also by objectively evaluating its safety limits, and to extend it to spectroscopy, for which our group has access to the appropriate hardware, exploiting the same characteristics of repeatability and controllability of the electrical muscle stimulation. The velocity imaging sequence will be optimized by including the modern concept of simultaneous multislice imaging, in order to obtain volumetric coverage in reasonable scan time, and relaxometry methods currently used for the heart will be adapted to work in the muscle, in order to monitor changes in T1 and T2 during exercise.Once these steps are completed, we will focus on the development of interleaved imaging/spectroscopy methods, a concept which has been recently proposed, which would fuse the two main instruments of muscle functional imaging into a single acquisition.The second part of the project will be dedicated to the validation of the methods in a clinical setting on two different subject populations: on the one side, they will be used to objectively monitor the training of athletes (in collaboration with the Department of Sport, Exercise and Health (DSBG), Division Sports and Exercise Medicine of the University of Basel) and on the other side, they will be applied to the diagnosis and to the severity assessment of patients suffering from Becker muscular dystrophy (in collaboration with the Department of Neurology of the University Children's Hospital of Basel).In addition to the immediate scientific output, the outcome of this project will be a set of imaging and spectroscopy tools to be used in a clinical setting for the evaluation of the condition of muscles in different contexts, both pathological and physiological. The attractiveness of this setup is its ease of deployment and its low cost, which would make it implementable in a large number of clinics and hospitals equipped with a standard clinical MRI system.