Hypertrophic degeneration of olivary nucleus can be caused by the lesions of brainstem or pons tegmental tract at the same side. MRI can clearly demonstrate HOD, thus, improve its diagnosis.

• 桥脑及中脑被盖束病变可以引起同侧下橄榄核发生肥大性变性 ,MRI可以清晰显示HOD病变 ,可提高对该病变的认识 ,避免误诊