title: Ataxia of Charlevoix-Saguenay: MR and Clinical Results in Lower-Limb Musculature.
abstract: OBJECTIVE
  Peripheral neuropathy is a cardinal manifestation of the autosomal recessive spastic ataxia of Charlevoix- Saguenay (ARSACS), although its type of neuromuscular involvement has not been definitely established, and magnetic resonance imaging (MRI) plays an important role in the assessment of muscle and nerve diseases. The objective of this work has been to define the patterns of muscle weakness and of abnormal muscular MRI in ARSACS.
  
  
  METHODS
  Five patients with a molecular diagnosis of ARSACS, aged 39 to 59 years, whose electrophysiological findings were consistent with an axonal neuropathy of distal distribution superimposed on a developmental defect of myelinization, underwent neurological and MRI lower-limb examinations. Conventional FSE T1-weighted and STIR sequences were performed, looking for fatty infiltration and oedema in the musculature of the thighs, legs and feet, together with their distribution along the longitudinal axis of the muscle bellies.
  
  
  RESULTS
  On clinical examination, paralysis was apparent in foot muscles; moderate weakness, in leg musculature; and normal strength, in thigh muscles. MRI demonstrated massive fat deposition in the foot muscles and medial gastrocnemii in every case, distal fat infiltration and oedema in every leg muscle group, and preservation of thigh muscles, albeit with diffuse minimal non-specific fat infiltration. An inverse correlation between strength and degree of fat infiltration in lower-limb muscles became apparent.
  
  
  CONCLUSIONS
  The preponderance of weakness and MRI abnormalities in distal muscle groups was concordant with the presence of a length-dependent axonopathy, as described in ARSACS.
  
  
  
  Ataxie de Charlevoix-Saguenay : IRM et observations cliniques au niveau de la musculature des membres inférieurs.
authors.forename: José
authors.initials: J
authors.lastname: Gazulla
authors.forename: Esteban
authors.initials: E
authors.lastname: Mayayo-Sinués
authors.forename: Isabel
authors.initials: I
authors.lastname: Benavente
authors.forename: Pedro J
authors.initials: PJ
authors.lastname: Modrego
authors.forename: José
authors.initials: J
authors.lastname: Berciano
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007866:Leg / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009128:Muscle Spasticity / Q000150:complications / Q000175:diagnosis*; D018908:Muscle Weakness / Q000150:complications / Q000175:diagnosis*; D018482:Muscle, Skeletal / Q000473:pathology*; D020754:Spinocerebellar Ataxias / Q000150:complications / Q000151:congenital* / Q000175:diagnosis