Hypertrophic Olivary Degeneration and Holmes Tremor: Case Report and Review of the Literature

Hypertrophic olivary degeneration (HOD) is very rare type of degeneration that causes hypertrophy rather than atrophy. The classical presentation of HOD is palatal myoclonus. However, HOD may rarely present with Holmes tremor (HT). HT is unusual symptomatic tremor characterized by combination of rest and intention tremor. It has been reported in small case series, so far. In this study, a man aged 62 years with HOD and HT spreading to the upper and lower extremities after pontine-midbrain hemorrhage due to cavernoma was presented. Although pontine-midbrain hemorrhage may cause HT in the late period, HOD can be revealed on magnetic resonance imaging. Tract anatomy, especially the Guillain-Mollaret triangle, should be considered to explain the relationship between HT and HOD.