Intercontinental validation of brain volume measurements using MSmetrix.

Background Brain volume assessment has become an important outcome within research and treatment of multiple sclerosis (MS). MSmetrix (Icometrix) has been developed specifically for patients with MS. The original healthy, 'normal' population used for determination of the acceptable brain volume data consisted mainly of Europeans. Methods In the present study, results from 295 completely normal magnetic resonance imaging scans from Brazilian subjects were plotted against the original results in MSmetrix. Results With regard to whole brain volume, only 2% of the healthy adult subjects from Brazil were below the 5th percentile of the graph, and for grey matter volume, only 3% of the subjects were below the 5th percentile of MSmetrix standards. Conclusion MSmetrix may be used across different populations.