Quantitative brain MRI in patients with alpha-mannosidosis: Study from 3 centers

Introduction: Alpha-mannosidosis is a rare lysosomal storage disease with multisystemic abnormalities and a wide clinical variability. The primary clinical brain MRI findings are described in case report studies. Quantitative MRI outcomes using robust automated methods as a prerequisite for clinical trials are not available. Methods: High-resolution T1-weighted MRI scans of 6 subjects (age: range 6-27 mean ± SD 14.5±4.9 years of age) with alpha-mannosidosis acquired on clinical MRI scanners were evaluated by automated volumetric analysis and compared to MRIs of 80 healthy controls (age: range 6-25 mean ± SD 14.0±7.7 years of age). Brain volumes were adjusted for intracranial volume and age. Results: Lower volumes of total cerebral grey matter (specifically putamen*, caudate**, and thalamus*) and cerebellum* (both white* and grey* matter) were observed in patients. No change was seen in volumes of cerebral cortex, corpus callosum, total cerebral white matter, and brainstem. (*p