[MR Tomographic Aspects of Olivary Pseudohypertrophy]

MRI aspects of olivary pseudohypertrophy (OH) following pontocerebellar lesions of different etiology and localization are reviewed. OH is characterized by unilateral or bilateral enlargement of the inferior olivary nucleus and increased signal intensity in T2- and, especially, in proton-density (PD)-weighted images. Correlations between the extent and the uni- or bilateral presence of olivary hypertrophy and the localization of the primary pontocerebellar lesions are discussed.