Magnetic resonance imaging in children with neurological disorders

Four children with neurological disorders were examined with a Picker Vista-MR imager using a 0.5 tesla (T) superconducting magnet operated at 0.256 T. We separated images into T1 and T2 weighted. T1 weighted images were obtained using inversion recovery (IR) sequences or spin echo (SE) sequences with short echo time (TE) and short repetition (TR) (TE : 40 msec, TR : 0.4 sec). T2 weighted images had long TE and TR (TE : 80 msec, TR : 2.0 sec). In a 6-month-old girl with congenital muscular dystrophy (Fukuyama type), there were bilateral symmetrical high signal intensities (T2 weighted image) and low signal intensities (T1 weighted images) in white matter. But IR coronal images showed symmetrical high signal intensities within the posterior limb of internal capsule, thalami and some part of corpus callosum. In a 9-year-old girl with acute relapsing disseminated encephalomyelitis, lesions showed higher intensities than normal brain tissues on T2 weighted images. However, lesions could not be identified on T1 weighted images, because lesions had the same signal intensities as the surrounding tissues. In two children with tuberous sclerosis, T2 weighted images disclosed numerous uncalcified nodules within the cortex and foramen Monro, although CT scan revealed no abnormalities in the same regions. On T1 weighted images, we could not recognize the lesions at the margins of the brain and CSF by partial volume effects. MRI is a sensitive method for detecting the lesions in the central nervous system. We emphasized that T2 weighted images were useful for detection of lesions. (author)