[Brain magnetic resonance imaging findings in two cases of Hunter's syndrome].

Magnetic resonance (MR) imaging findings in two cases of Hunter's syndrome [mucopolysaccharidosis (MPS) type II A] are reported. The first case is a 15-year-old boy in whom the diagnosis of Hunter's syndrome was made at 2 years of age on the basis of increased glycosaminoglycans in the urine, developmental delay, characteristic faces, joint contraction, family histories, and radiological characteristics including oar-like deformed ribs and dysplasia of lumbar vertebrae. MR images showed marked enlargement of the lateral ventricles and third ventricle. The cerebral cortical sulci were diffusely dilated. Abnormal intensity lesions in the lateral part of the lentiform nucleus, the subcortex of the insula, the pons, and the right thalamus were seen. Diffuse hyperintensity throughout the periventricular white matter is also seen on T2-weighted images. The second case is a 3-year-old boy, born at immature delivery. At 2 months of age, he was admitted to a pediatric department because of liver dysfunction, inguinal hernias and umbilical hernia. The diagnosis of Hunter's syndrome was made by developmental delay, gargoylism, joint contraction, kyphosis, and biochemical investigation of urine. Urinary glycosaminoglycans significantly increased. Skeletal radiography showed dysplasia of the lumbar vertebrae and acetabulum. T1-weighted MR images demonstrated numerous hypointense spots in the corpus callosum and the cerebral white matter, presumably suggesting large perivascular spaces. Multiple cystic changes appeared to be hyperintense on T2-weighted images. Numerous linear hyperintense lesions were visible in the corona radiata. Patchy areas of hyperintense areas were seen, more prominent in the parietal lobes. Neuropathological examinations in cases of Hunter's syndrome have previously shown marked dilatation of ventricular system, large perivascular spaces secondary to mucopolysaccharide storage, demyelination and gliosis in the white matter and so forth. MR findings correlated well with previously reported neuropathological findings. MR study is not only useful for diagnosing Hunter's syndrome but also helpful to follow the pathological status.