2777 Hypertrophic olivary degeneration secondary to long-standing brainstem and cerebellar cavernomata

• Published in: BMJ neurology open Vol. 5; no. Suppl 1; p. A51
• Main Authors: Mulcahy, Liam, Irani, Neha, O’Connor, Kevin, Nathani, Dev, David, Shivlal
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd 01.08.2023; BMJ Publishing Group LTD
• Subjects: Ataxia; Dysarthria; Hemorrhage; Neurological disorders; Poster Abstract
• ISSN: 2632-6140
• DOI: 10.1136/bmjno-2023-ANZAN.142

IntroductionHypertrophic olivary degeneration (HOD) is a rare complication of brainstem cavernoma.Case ReportWe present a case of a 66-year-old man with 12-month history of progressive ataxia, dysarthria, ophthalmoplegia and palatal tremor. Remote medical history is notable for two previous strokes, at ages of 4 and 24 years, presumed to be haemorrhagic, although medical records from four decades prior were not available for confirmation.Examination was notable for severe dysarthria, right gaze palsy along with partial internuclear ophthalmoplegia (partial one-and-a-half syndrome), right fascicular abducens nerve palsy, gaze evoked jerk nystagmus, skew deviation, rhythmic palatal tremor, mild left facial nerve palsy, left upper and lower limb weakness and hypertonia, moderately severe bilateral upper and lower limb ataxia.CT and MRI brain demonstrated multiple supra and infratentorial cavernomata, prominently in pons and right cerebellum. There was subacute haemorrhage into a right thalamic cavernoma and T2-hyperintensity in both olivary nuclei, characteristic of HOD. Based on available neuroimaging from 12 years prior, the right cerebellar cavernoma and HOD were new findings along with enlargement of the pontine cavernoma. FDG-PET scan demonstrated hypometabolism involving bilateral, right more than left, cerebellar hemispheres and the pons.DiscussionBrainstem cavernoma as the aetiology of HOD is extremely rare. Although this patient did not present with symptomatic brainstem haemorrhage, it is likely that he had subclinical haemorrhage leading to Wallerian degeneration and subsequent development of HOD. This case sheds light on the natural history of brainstem cavernoma and highlights the rare potential complication of HOD.