The value of CT in diagnosis and prognosis of different inborn neurodegenerative disorders in childhood.

Inborn errors of metabolism in 40 children have been investigated by computed tomography to obtain data on the degree of cerebral involvement in neurodegenerative and storage disorders: 20 children had various mucopolysaccharidoses, 8 sphingolipidoses , 3 mucolipidoses, 2 oligosaccharidoses , 3 ceroidlipofuscinoses and 4 had various leucodystrophies . Diagnosis in all patients except Alexander's disease was established by biochemical or histological means. The main findings on CT were cerebral atrophy with enlargement of the ventricles and the subarachnoid spaces and hypodensity of the white matter. The degree of cerebral atrophy seemed to develop according to the age of the patients, as could be seen from the patients with mucopolysaccharidosis III, metachromatic leucodystrophy and GM1-gangliosidosis. Hypodensity of the white matter was found in mucopolysaccharidosis I-H, II-B, VI, in mucolipidosis II and in patients with leucodystrophies . On the other hand, there was great variability in these CT findings even in siblings, as seen in four patients with mucopolysaccharidosis VI. Among the series there were several patients who did not show any abnormalities in CT, so that a negative CT did not exclude these disorders, even the leucodystrophies . CT features such as cerebral atrophy or hypodensity were helpful in the evaluation of these disorders, though a diagnosis could not be made by CT alone.