Hypertrophic olivary degeneration: MR imaging and pathologic findings.
OBJECTIVE
To assess magnetic resonance (MR) imaging findings of hypertrophic olivary degeneration (HOD) due to hemorrhage and correlate them with pathologic findings.


METHODS
MR imaging was performed in 11 patients--eight with pontine tegmental hemorrhages (THs) and three with cerebellar hemorrhages in the dentate nuclei. The interval from hemorrhagic ictus to the MR studies was 3 weeks to 49 months. Pathologic specimens came from a woman who died of brain stem hemorrhage.


RESULTS
Involvement of the central tegmental tract produced ipsilateral HOD; that of the dentate nucleus or superior cerebellar peduncle produced contralateral HOD. Bilateral olivary changes occurred only when the TH also involved the superior cerebellar peduncle. In bilateral THs, HOD was limited to the dominant bleeding side because of the lateral position of the central tegmental tract. Hyperintense areas of the oliva appeared 3 weeks after ictus. Hypertrophy appeared after 5-15 months. Microscopically, vacuolar degeneration of neurons and hypertrophy of astrocytes with gliosis were seen.


CONCLUSIONS
MR images may depict very early neuronal changes in the oliva and are well correlated with pathologic staging.
Kitajima
M
M
Department of Radiology, Kumamoto University School of Medicine, Japan.
Korogi
Y
Y
Shimomura
O
O
Sakamoto
Y
Y
Hirai
T
T
Miyayama
H
H
Takahashi
M
M
D000328:Adult; D000368:Aged; D001927:Brain Diseases / Q000175:diagnosis / Q000473:pathology; D002543:Cerebral Hemorrhage / Q000150:complications / Q000473:pathology; D005260:Female; D006801:Humans; D006984:Hypertrophy; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009847:Olivary Nucleus / Q000473:pathology*; D012189:Retrospective Studies