title: Magnetic resonance imaging of the proximal upper extremity musculature in boys with Duchenne muscular dystrophy.
abstract: There is a pressing need for biomarkers and outcomes that can be used across disease stages in Duchenne muscular dystrophy (DMD), to facilitate the inclusion of a wider range of participants in clinical trials and to improve our understanding of the natural history of DMD. Quantitative magnetic resonance imaging (qMRI) and spectroscopy (MRS) biomarkers show considerable promise in both the legs and forearms of individuals with DMD, but have not yet been examined in functionally important proximal upper extremity muscles such as the biceps brachii and deltoid. The primary objective of this study was to examine the feasibility of implementing qMRI and MRS biomarkers in the proximal upper extremity musculature, and the secondary objective was to examine the relationship between MR measures of arm muscle pathology and upper extremity functional endpoints. Biomarkers included MRS and MRI measures of fat fraction and transverse relaxation time (T2). The MR exam was well tolerated in both ambulatory and non-ambulatory boys. qMR biomarkers differentiated affected and unaffected participants and correlated strongly with upper extremity function (r = 0.91 for biceps brachii T2versus performance of upper limb score). These qMR outcome measures could be highly beneficial to the neuromuscular disease community, allowing measurement of the quality of functionally important muscles across disease stages to understand the natural history of DMD and particularly to broaden the opportunity for clinical trial participation.
authors: Department of Physical Therapy, University of Florida, Gainesville, FL, USA. rw254@phhp.ufl.edu.
authors: R J
authors: RJ
authors: Willcocks
authors: Department of Physical Therapy, University of Florida, Gainesville, FL, USA.
authors: W T
authors: WT
authors: Triplett
authors: Department of Physical Therapy, University of Florida, Gainesville, FL, USA.
authors: S C
authors: SC
authors: Forbes
authors: Department of Physical Therapy, University of Florida, Gainesville, FL, USA.
authors: H
authors: H
authors: Arora
authors: Department of Physical Therapy, University of Florida, Gainesville, FL, USA.
authors: C R
authors: CR
authors: Senesac
authors: Department of Physical Therapy, University of Florida, Gainesville, FL, USA.
authors: D J
authors: DJ
authors: Lott
authors: Advanced Magnetic Resonance Imaging and Spectroscopy Facility, University of Florida, Gainesville, FL, USA.
authors: T R
authors: TR
authors: Nicholson
authors: Advanced Imaging Research Center, Oregon Health and Science University, Portland, OR, USA.
authors: W D
authors: WD
authors: Rooney
authors: Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL, USA.
authors: G A
authors: GA
authors: Walter
authors: Department of Physical Therapy, University of Florida, Gainesville, FL, USA.
authors: K
authors: K
authors: Vandenborne
mesh_terms: D000293:Adolescent; D015415:Biomarkers / Q000378:metabolism; D002648:Child; D005240:Feasibility Studies; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging* / Q000378:metabolism; D020388:Muscular Dystrophy, Duchenne / Q000000981:diagnostic imaging* / Q000378:metabolism; D034941:Upper Extremity / Q000000981:diagnostic imaging*
chemical_list: D015415:Biomarkers
keywords: Biomarker; Magnetic resonance spectroscopy; Non-ambulatory; Transverse relaxation time