CONGENITAL MUSCULAR-DYSTROPHY - USE OF BRAIN MR-IMAGING FINDINGS TO PREDICT MEROSIN DEFICIENCY

PURPOSE: To evaluate the brain magnetic resonance (MR) imaging finding s in patients with the ''classic'' form of congenital muscular dystrop hy (patients with normal intelligence) in relation to the absence of m erosin, a recently identified molecular component in the basement memb rane of muscle fiber. MATERIALS AND METHODS: Brain MR images in 15 pat ients (13 children, two adults) were reviewed and correlated with the patient's merosin status. Merosin was evaluated by means of immunocyto chemical study of specimens from muscle biopsy. RESULTS: Nine patients had merosin deficiency. All patients had diffuse white matter alterat ions similar to those seen in cases of leukodystrophy. Periventricular and subcortical white matter were involved. The corpus callosum and i nternal capsule were spared. Follow-up MR images were available in two patients; changes were nonprogressive. White matter signal intensity was normal in the six patients with normal uniform labeling against me rosin. Ventricular dilatation and cortical atrophy were observed in bo th groups. CONCLUSION. Diffuse white matter changes resembling those s een with leukodystrophy may be a valuable criterion for diagnosis of m erosin deficiency in patients with classic congenital muscular dystrop hy.