MRI brain volumetry in Rasmussen encephalitis: The fate of affected and “unaffected” hemispheres

Abstract

Rasmussen encephalitis (RE) is regarded as a unihemispheric disease. Serial three-dimensional MRIs of 18 patients under immunotherapy were analyzed volumetrically and planimetrically. Median volume loss was significantly higher in the affected than in the unaffected hemispheres (29.9 cm³/y vs 6.8 cm³/y). Correlation of the planimetrically and volumetrically assessed hemispheric ratios (HRs) was significant. The results support the concept of RE as a basically unilateral disease. Planimetric HR assessment is valid and time efficient.