Iron deposits in the red nucleus at long-term follow-up after hypertrophic olivary degeneration.

Abstract

Hypertrophic olivary degeneration (HOD) is an uncommon trans-synaptic degenerating disease characterized by hypertrophy of the inferior olivary nucleus (ION). The disease typically results from interruptions of connections in the dentato-rubro-olivary pathway (DROP) or Guillain-Mollaret triangle (GMT), which encompasses the ipsilateral red nucleus (RN), ipsilateral ION, and contralateral dentate nucleus (DN). Before the advent of magnetic resonance imaging (MRI), HOD was only detectable by autopsy; however, MRI now makes it possible to diagnose HOD in vivo. Most reports about HOD are based on conventional MRI, with only one report using susceptibility-weighted imaging (SWI) (1), and no reports on combined application of SWI and diffusion tensor imaging (DTI). This report presents a case of unilateral HOD in a 66-year-old male 4 years post-cerebellar hemorrhage, who was examined with both SWI and DTI.