Magnetic resonance imaging of muscle in congenital myopathies associated with RYR1 mutations.
Mutations in the skeletal muscle ryanodine receptor (RYR1) gene are associated with a wide range of phenotypes, comprising central core disease and distinct subgroups of multi-minicore disease. We report muscle MRI findings of 11 patients from eight families with RYR1 mutations (n=9) or confirmed linkage to the RYR1 locus (n=2). Patients had clinical features of a congenital myopathy with a wide variety of associated histopathological changes. Muscle MR images showed a consistent pattern characterized by (a) within the thigh: selective involvement of vasti, sartorius, adductor magnus and relative sparing of rectus, gracilis and adductor longus; (b) within the lower leg: selective involvement of soleus, gastrocnemii and peroneal group and relative sparing of the tibialis anterior. Our findings indicate that patients with RYR1-related congenital myopathies have a recognizable pattern of muscle involvement irrespective of the variability of associated histopathological findings. Muscle MRI may supplement clinical assessment and aid selection of genetic tests particularly in patients with non-diagnostic or equivocal histopathological features.
Jungbluth
Heinz
H
Department of Paediatric Neurology, Guy's Hospital, London, UK. h.jungbluth@imperial.ac.uk
Davis
Mark R
MR
Müller
Clemens
C
Counsell
Serena
S
Allsop
Joanna
J
Chattopadhyay
Arijit
A
Messina
Sonia
S
Mercuri
Eugenio
E
Laing
Nigel G
NG
Sewry
Caroline A
CA
Bydder
Graeme
G
Muntoni
Francesco
F
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004252:DNA Mutational Analysis; D003937:Diagnosis, Differential; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005820:Genetic Testing; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D009154:Mutation / Q000235:genetics*; D020914:Myopathies, Structural, Congenital / Q000235:genetics* / Q000473:pathology*; D020512:Myopathy, Central Core / Q000235:genetics / Q000473:pathology; D019683:Penetrance; D010641:Phenotype; D011237:Predictive Value of Tests; D019837:Ryanodine Receptor Calcium Release Channel / Q000235:genetics*; D013848:Thigh / Q000473:pathology
D019837:Ryanodine Receptor Calcium Release Channel