title: Thigh muscle volume measured by magnetic resonance imaging is stable over a 6-month interval in spinal muscular atrophy.
abstract: Changes in thigh muscle volume over 6 months were assessed using magnetic resonance imaging in 11 subjects aged 6 to 47 years with spinal muscular atrophy (4 type 2 and 7 type 3; 4 ambulatory and 3 nonambulatory). Muscle volume with normal and abnormal signal was measured using blinded, semiautomated analysis of reconstructed data. Volumes at baseline and 6 months were correlated with clinical function at each epoch. There was minimal increase in normal (0.3 ± 1.4 mL/cm) and total (0.1 ± 1.3 mL/cm) muscle. Muscle volume correlated closely with clinical function. Minimal interval change in muscle volume is consistent with the established clinical history of minimal disease progression over intervals shorter than 1 year. Relative constancy of muscle volume estimation and correlation with established functional measures suggest a role for segmental magnetic resonance imaging as a biomarker of treatment effect in future therapeutic trials.
authors.affiliation: Division of Pediatric Neurosciences, Department of Neurology, SMA Clinical Research Center, Columbia University Medical Center, New York, NY 10032-3791, USA. dms98@columbia.edu
authors.forename: Douglas M
authors.initials: DM
authors.lastname: Sproule
authors.forename: Megan J
authors.initials: MJ
authors.lastname: Montgomery
authors.forename: Mark
authors.initials: M
authors.lastname: Punyanitya
authors.forename: Wei
authors.initials: W
authors.lastname: Shen
authors.forename: Stephen
authors.initials: S
authors.lastname: Dashnaw
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Montes
authors.forename: Sally
authors.initials: S
authors.lastname: Dunaway
authors.forename: Richard
authors.initials: R
authors.lastname: Finkel
authors.forename: Basil
authors.initials: B
authors.lastname: Darras
authors.forename: Darryl C De
authors.initials: DC
authors.lastname: Vivo
authors.forename: Petra
authors.initials: P
authors.lastname: Kaufmann
mesh_terms: D000293:Adolescent; D000328:Adult; D000886:Anthropometry; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology*; D009134:Muscular Atrophy, Spinal / Q000145:classification / Q000175:diagnosis* / Q000503:physiopathology; D009460:Neurologic Examination; D013223:Statistics as Topic; D013848:Thigh / Q000473:pathology*; D055815:Young Adult