Hypertrophic olivary degeneration

Case contributed by Dr Yune Kwong

Presentation

2 MRIs 8 months apart

Patient Data

Age: 65-70 years
Gender: Female

MRI brain

Modality: MRI

Initial scan performed for assessment of giant supra-sellar aneurysm. Patient had VP shunt (into corpus callosum!) for persistent hydrocephalus following haemorrhage.  

MRI Brain 8 months later

Modality: MRI

On the follow-up scan, it is apparent that she has suffered haemorrhage into the pontine tegmentum. High signal and focal swelling is seen in the medulla (left > right).

Case Discussion

Hypertrophic olivary degeneration is secondary to trans-synaptic injury along the dentato-rubral-olivary pathway (better known as the triangle of Guillain-Mollaret). It is an unusual type of degeneration because it is associated with enlargement, rather than atrophy, of the inferior olivary neurons. Pathologically, it corresponds to vacuolar degeneration of cytoplasm that results in enlargement.

It is important to recognise this pattern of injury so that the changes in the medulla are not ascribed to a more serious cause eg tumour, demyelination or infarct. The most important clue to the correct diagnosis is the association of a remote lesion along the pathway.

PlayAdd to Share

Case Information

rID: 23110
Case created: 22nd May 2013
Last edited: 15th Dec 2015
Inclusion in quiz mode: Included

Updating… Please wait.
Loadinganimation

Alert accept

Error Unable to process the form. Check for errors and try again.

Alert accept Thank you for updating your details.