Neurological impairment in alpha-mannosidosis: a longitudinal clinical and MRI study of a brother and sister.

Neurological development over a period of 25 years and MRI findings are reported in two members of the same family affected by mannosidosis type II. Progressive axial and appendicular cerebellar syndrome, moderate hearing loss and deterioration of gait were present in both patients. Neuropsychological deficiency was severe, but progression over the years was not observed except in the woman's speech capacity. Neither of the patients showed clinical improvement. A progressive corticosubcortical atrophy stands out in the brain neuroimaging studies, especially at the vermian cerebellar level. The osseous cranial deformities are very characteristic and include brachycephaly, thickening of the calvaria at the expense of the diploe, and poor pneumatization of the sphenoid. Neither of our cases showed an empty sella turcica.